Perovskite quantum dots are emerging as attractive materials for photonic and optoelectronic applications. Patterning is an important step to incorporate them into display, anti‐counterfeiting, and ...optical chip applications. In this work, an in situ inkjet printing strategy is demonstrated for fabricating perovskite quantum dots patterns by printing perovskite precursor solutions onto a polymeric layer. Importantly, this strategy can achieve bright photoluminescence with a quantum yield up to 80% and shows broad applicability to a variety of perovskites and polymers. Moreover, the as‐fabricated perovskite quantum dots patterns are composed of a microdisks array on the surface of polymeric layer. The size of these microdisks can be varied by adjusting the printing temperature. To demonstrate the potential use in display and advanced anti‐counterfeiting applications, color pixel patterns and 2D code pattern are fabricated by varying the precursor solutions. The combination of superior photoluminescence properties, simple process, and low cost makes the in situ inkjet printing strategy very promising for patterning perovskite quantum dots toward photonic integrations.
An in situ inkjet printing strategy is developed for fabricating perovskite quantum dot patterns by printing perovskite precursor solutions onto a polymeric layer. The strategy is versatile, simple, and low cost to achieve color pixel patterns and/or 2D codes with strong photoluminescence, which are promising for anti‐counterfeiting and display applications.
The South China Block, consisting of the Yangtze and the Cathaysia blocks, is one of the largest Precambrian blocks in eastern Asia. However, the early history of the Cathaysia Block is poorly ...understood due largely to intensive and extensive reworking by Phanerozoic polyphase orogenesis and magmatism which strongly overprinted and obscured much of the Precambrian geological record. In this paper, we use the detrital zircon U–Pb age and Hf isotope datasets as an alternative approach to delineate the early history of the Cathaysia Block. Compilation of published 4041 Precambrian detrital zircon ages from a number of (meta)sedimentary samples and river sands exhibits a broad age spectrum, with three major peaks at ~2485Ma, ~1853Ma and ~970Ma (counting for ~10%, ~16% and ~24% of all analyses, respectively), and four subordinate peaks at ~1426Ma, ~1074Ma, ~780Ma and ~588Ma. Five of seven detrital zircon age peaks are broadly coincident with the crystallisation ages of ~1.89–1.83Ga, ~1.43Ga, ~1.0–0.98Ga and ~0.82–0.72Ga for known igneous rocks exposed in Cathaysia, whereas, igneous rocks with ages of ~2.49Ga and ~0.59Ga have not yet been found. The Hf isotopic data from 1085 detrital zircons yield Hf model ages (TDMC) between ~4.19Ga and ~0.81Ga, and the calculated εHf(t) values between −40.2 and 14.4. The Archean detrital zircons are exclusively oval in shape with complicated internal textures, indicating that they were sourced by long distance transportations and strong abrasion from an exotic Archean continent. In contrast, the majority of detrital zircons in age between ~1.9 and ~0.8Ga are euhedral to subhedral crystals, indicative of local derivation by short distance transportations from their sources. The oldest crustal basement rocks in Cathaysia were most likely formed by generation of juvenile crust and reworking of recycled Archean components in Late Paleoproterozoic at ~1.9–1.8Ga, rather than in the Archean as previously speculated. Reworking and recycling of the continental crust are likely the dominant processes for the crustal evolution of Cathaysia during the Mesoproterozoic to Neoproterozoic time, with an intervenient period of significant generation of juvenile crust at ~1.0Ga.
Precambrian crustal evolutions of the Cathaysia Block are genetically related to the supercontinent cycles. By comparing detrital zircon data from Cathaysia with those for other continents, and integrating multiple lines of geological evidence, we interpret the Cathaysia Block as an orogenic belt located between East Antarctica, Laurentia and Australia during the assembly of supercontinent Columbia/Nuna at ~1.9–1.8Ga. The Cathaysia Block amalgamated with the Yangtze Block to form the united South China Block during the Sibao Orogeny at ~1.0–0.89Ga. The Laurentia–Cathaysia–Yangtze–Australia–East Antarctica connection gives the best solution to the paleo-position of Cathaysia in supercontinent Rodinia. The significant amount of ~0.6–0.55Ga detrital zircons in Cathaysia and West Yangtze have exclusively high crustal incubation time of >300Ma, indicating crystallisation from magmas generated dominantly by crustal reworking. This detrital zircon population compares well with the similar-aged zircon populations from a number of Gondwana-derived terranes including Tethyan Himalaya, High Himalaya, Qiangtang and Indochina. The united South China–Indochina continent was likely once an integral part of Gondwanaland, connected to northern India by a “Pan-African” collisional orogen.
Display omitted
•Cathaysia Block formed at ~1.9-1.8Ga, rather than in Archean.•Archean detrital zircons found in Cathaysia were likely sourced from East Antarctica.•Cathaysia locates between E. Antarctica, Laurentia and Australia in Columbia/Nuna.•South China most likely locates in the interior, but not on fringe, of Rodinia.•South China connects with Northern India by a “Pan-African” collisional orogeny.
It has been widely accepted that an active continental margin existed along the coast of Southeast China during the Mesozoic time that produced extensive magmatism in the region. However, there is ...little constraint as to when this active margin was first initiated. Here we present new SHRIMP U‐Pb zircon ages and geochemical and Sr‐Nd isotopic data for syntectonic granites on Hainan Island. Our data demonstrate that these rocks, dated at 267–262 Ma, are typical of calc‐alkaline I‐type granites formed in continental arc environments. The age of this magmatic arc coincides with a sudden change in sedimentary environments in South China during the Permian time, suggesting that the South China Indosinian Orogeny was likely contemporaneous with the onset of continental arc magmatism.
The Mesozoic geology of SE China is characterized by widespread Jurassic to Cretaceous igneous rocks consisting predominantly of granites and rhyolites and subordinate mafic lithologies. However, the ...tectonic regime responsible for the inland Jurassic granites remains controversial. We report here U–Pb zircon ages, geochemical and Sr–Nd–Hf isotopic data for the Nankunshan alkaline granite and the Fogang granitic batholith in central Guangdong. Mineralogical and geochemical features suggest that the Fogang and Nankunshan rocks are I- and aluminous A-type granites, respectively. SHRIMP U–Pb zircon analyses yield consistent ages ranging from 159
±
3 Ma to 165
±
2 Ma for four samples from the Fogang Batholith, and an age of 158
±
5 Ma for the Nankunshan Granite. The Fogang granites, having
I
Sr
=
0.7098–0.7136,
εNd(
T)
=
−
4.3 to −
12.2 and
εHf(
T)
=
−
11.5 to −
3.1 for the magmatic zircons, were derived from Paleoproterozoic mafic-intermediate igneous protolith with minor addition of mantle-derived magmas. The Nankunshan rocks have relatively lower
I
Sr
≈
0.706–0.708, higher
εNd(
T)
=
0.3 to −
2.4 and
εHf(
T)
=
−
5.7 to 1.1 for the magmatic zircons, and some OIB-like trace element ratios. They were likely generated through extensive fractional crystallization of mantle-derived alkaline parental magma associated with crustal assimilation. These ∼
160 Ma I- and A-type granites in central Guangdong were emplaced coeval with the widespread 165–155 Ma I- and A-type granites and syenites following the initiation of intraplate basaltic and/or bimodal igneous magmatism at 180–170 Ma in the adjacent regions. We interpret these Jurassic igneous rocks as anorogenic magmatism formed during a major igneous event in response to foundering of an early Mesozoic subducted flat-slab beneath SE China continent.
Detrital zircon provenance data for the Tananao schist in eastern Taiwan is consistent with its protolith being deposited on the South China continental margin at around, or soon after, 150Ma, rather ...than being of an exotic origin and much older as previously suggested. The absence of ca. 200Ma zircons agrees with the presence of a magmatic gap in the region after the orogenic and magmatic front migrated to central South China, due to a flat-slab subduction. The characteristic lack of input from interior South China (i.e., the lack of 1100–750Ma and 470–420Ma populations), and the immature nature of some of the schist units, suggest that they were sourced from the nearby coastal regions. On the other hand, they exhibit a dominant 190–150Ma magmatic zircon population, suggesting the presence of abundant magmatic rocks of that age along the coastal regions. This, along with our newly discovered ca. 180Ma I-type granites from eastern Zhejiang and other ca. 190–180Ma magmatic rocks recently reported from the coastal regions, led us to propose that a new continental arc was initiated after ca. 190Ma along the coastal region after a magmatic gap due to flat-slab subduction. This newly initiated arc likely persisted until ca. 90Ma, and is represented by the I-type granitic rocks in eastern Taiwan. Slab roll-back likely caused the arc system to retreat towards the Pacific Ocean after 90Ma, and ca. 60–17Ma bimodal magmatism adjacent to the South China Sea signifies continental margin extension in the lead-up to, and during, the opening of the South China Sea. We thus argue that the continental margin of East Asia was transformed from an Andean-type plate margin at 280–90Ma, to the present-day Western Pacific-type plate margin soon after 90Ma.
Display omitted
► Support the flat-slab subduction model for Mesozoic South China. ► Confirm that a new continental magmatic arc was reinitiated as early as ca. 190Ma. ► Suggest an Andean-type plate margin during 280–90Ma. ► The Western Pacific-type plate margin started soon after ca. 90Ma.
During the spring of 2013, a novel avian-origin influenza A (H7N9) virus emerged and spread among humans in China. Data were lacking on the clinical characteristics of the infections caused by this ...virus.
Using medical charts, we collected data on 111 patients with laboratory-confirmed avian-origin influenza A (H7N9) infection through May 10, 2013.
Of the 111 patients we studied, 76.6% were admitted to an intensive care unit (ICU), and 27.0% died. The median age was 61 years, and 42.3% were 65 years of age or older; 31.5% were female. A total of 61.3% of the patients had at least one underlying medical condition. Fever and cough were the most common presenting symptoms. On admission, 108 patients (97.3%) had findings consistent with pneumonia. Bilateral ground-glass opacities and consolidation were the typical radiologic findings. Lymphocytopenia was observed in 88.3% of patients, and thrombocytopenia in 73.0%. Treatment with antiviral drugs was initiated in 108 patients (97.3%) at a median of 7 days after the onset of illness. The median times from the onset of illness and from the initiation of antiviral therapy to a negative viral test result on real-time reverse-transcriptase-polymerase-chain-reaction assay were 11 days (interquartile range, 9 to 16) and 6 days (interquartile range, 4 to 7), respectively. Multivariate analysis revealed that the presence of a coexisting medical condition was the only independent risk factor for the acute respiratory distress syndrome (ARDS) (odds ratio, 3.42; 95% confidence interval, 1.21 to 9.70; P=0.02).
During the evaluation period, the novel H7N9 virus caused severe illness, including pneumonia and ARDS, with high rates of ICU admission and death. (Funded by the National Natural Science Foundation of China and others.).
Adakites, or adakitic rocks, in a broad sense, have been used to describe a large range of igneous rocks with the common feature of high Sr/Y and La/Yb ratios that can be achieved though different ...mechanisms. Among them, the continental, or C-type, adakitic rocks are particularly controversial in terms of their sources and genesis. In this study we revisit both Cu–Au ore-bearing and barren “C-type adakitic rocks” in the Lower Yangtze River Belt (LYRB) of central eastern China, including comprehensive analyses of their in-situ zircon Hf–O isotopes, whole-rock geochemistry and Sr–Nd isotopes. These “C-type adakitic rocks” consist of monzodiorite, granodiorite and quartz monzonite that are classified as shoshonitic to high-K calc-alkaline series according to their chemical compositions. They are characteristically high in potassium (K2O=2.4–4.5%, K2O/Na2O=0.6–1.3), with continental crust-like isotopic compositions, i.e., whole-rock εNd(T)=−3.9 to −7.7, initial 87Sr/86Sr=0.7054–0.7085, zircon εHf(T)=0 to −11, and δ18O=6‰ to 9‰. The ore-bearing and barren rocks are cogenetic. Fractional crystallization of hornblende, titanite, magnetite and apatite played a major role in their chemical variations, with the ore-bearing rocks being more felsic (SiO2=63.3–69.6%) and higher in Sr/Y (41.2–75.6) than the barren rocks (SiO2=57.3–65.0%, Sr/Y=30.4–51.8). All these geochemical and isotopic features, in combination with regional geological data, suggest that the LYRB “C-type adakitic rocks” were unlikely to have been formed by melting of either a thickened and/or delaminated lower continental crust, or an altered oceanic crust as previously thought. These rocks are in general akin in geochemistry and isotopes to the Archean sanukitoids and the Setouchi high-Mg andesites in Japan, and are thus interpreted as being formed by melting of an enriched mantle source metasomatized by dewatering from a delaminated flat-slab. The flat subduction of an oceanic plateau and its subsequent delamination and foundering since the early Mesozoic beneath southeastern China (Li and Li, 2007) thus not only explain the temporal and spatial propagation of widespread Yanshanian igneous rocks regionally since ca. 195Ma, but also the formation of a series of enigmatic “adakitic” rocks in the region, including the LYRB potassium-rich rocks that were inappropriately called the “C-type adakitic rock” by previous workers.
•We revisit China's LYRB “C-type adakites” by Hf–O–Sr–Nd isotopes and geochemistry.•These rocks are potassium-rich monzodiorite, granodiorite and quartz monzonite.•They are derived from an enriched mantle source, not lower crust and oceanic crust.•“C-type adakites” are an inappropriate petrological classification for these rocks.•Delamination of subducted flat-slab accounts for widespread 195–85Ma igneous rocks.
Cancers are highly complex diseases that are characterized by not only the overgrowth of malignant cells but also an altered immune response. The inhibition and reprogramming of the immune system ...play critical roles in tumor initiation and progression. Immunotherapy aims to reactivate antitumor immune cells and overcome the immune escape mechanisms of tumors. Represented by immune checkpoint blockade and adoptive cell transfer, tumor immunotherapy has seen tremendous success in the clinic, with the capability to induce long-term regression of some tumors that are refractory to all other treatments. Among them, immune checkpoint blocking therapy, represented by PD-1/PD-L1 inhibitors (nivolumab) and CTLA-4 inhibitors (ipilimumab), has shown encouraging therapeutic effects in the treatment of various malignant tumors, such as non-small cell lung cancer (NSCLC) and melanoma. In addition, with the advent of CAR-T, CAR-M and other novel immunotherapy methods, immunotherapy has entered a new era. At present, evidence indicates that the combination of multiple immunotherapy methods may be one way to improve the therapeutic effect. However, the overall clinical response rate of tumor immunotherapy still needs improvement, which warrants the development of novel therapeutic designs as well as the discovery of biomarkers that can guide the prescription of these agents. Learning from the past success and failure of both clinical and basic research is critical for the rational design of studies in the future. In this article, we describe the efforts to manipulate the immune system against cancer and discuss different targets and cell types that can be exploited to promote the antitumor immune response.
The abundances of trace elements including Sr, Ga and rare earth elements (REE) and halogens in apatite crystals from four intermediate-felsic plutons in the Zhongdian terrane in the Sanjiang region ...have been determined using electron microprobe and laser ablation inductively coupled plasma mass spectrometry to evaluate the potential of apatite as a petrogenic-metallogenic indicator. The selected plutons include one that is not mineralized (the Triassic Xiuwacu pluton, or the TXWC pluton), one that hosts a porphyry-type Cu deposit (the Pulang pluton, or the PL pluton), one that hosts a porphyry-type Mo deposit (the Tongchanggou pluton, or the TCG pluton), and one that hosts a vein-type Mo deposit (the Cretaceous Xiuwacu pluton, or the CXWC pluton). Except for the CXWC pluton, the other three plutons have adakite-like trace element signatures in whole rocks. The results from this study show that REE, Sr and halogens in apatite can be used to track magma compositions, oxidation states and crystallization history. Apatite crystals from the adakite-like plutons are characterized by much higher Sr/Y and δEu than the non-adakite-type pluton. This means that apatite, which is not susceptible to alteration, is a useful tool for identifying the adakite-like plutons that no longer preserve the initial Sr/Y ratios in whole rocks due to weathering and hydrothermal alteration. Based on apatite Ga contents and δEu values, it is inferred that the parental magmas for the two adakite-like plutons containing porphyry-type Cu and Mo mineralization are more oxidized than that for the non-adakite-type pluton containing vein-type Mo mineralization. Apatite crystals from the vein-type Mo deposit have much lower Cl/F ratios than those from the porphyry-type Cu and Mo deposits. Apatite crystals from the adakite-like pluton without Cu or Mo mineralization is characterized by much lower Cl/F ratios than those from the adakite-like plutons that host the porphyry-type Cu and Mo deposits. The results from this study confirm the apatite is a useful petrogenetic indicator as well as mineral exploration tool.
•Sr, REE and halogens in apatite can track magmas compositions and crystallization history.•The positive correlation of Ga contents with Eu negative anomalies in apatite can indicate oxidation states of magmas.•The combination of Sr/Y ratios and δEu in apatite can identify adakite-like plutons.•Apatite compositions can reveal different magmatic conditions associated with porphyry-type Cu and Mo mineralization, vein-type Mo mineralization and barren mineralization.
We report here new field and analytical data from Precambrian rocks on Hainan Island of the Cathaysia Block, south China, and examine its probable connection to Laurentia. Granitoids and newly ...discovered felsic volcanic rocks dated at 1433 ± 6 Ma and 1439 ± 9 Ma (SHRIMP U‐Pb zircon) on Hainan Island are coeval with, and isotopically similar to the 1500–1350 Ma trans‐continental granite‐rhyolite province in southern Laurentia. Quartzites unconformably overlying the ca. 1430 Ma volcaniclastic rocks on Hainan Island are interpreted as locally‐sourced Grenvillian foreland basin deposits that can be correlated with the Deer Trail Group of south‐western Laurentia. The detrital provenance of the quartzites contains age populations comparable to the 1610–1490 Ma, westerly‐sourced non‐Laurentian detrital grains reported in the Belt Basin of south‐western Laurentia. Our new data thus make Cathaysia the most likely continental block next to western Laurentia before and during the late Mesoproterozoic assembly of Rodinia.
PDF
