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Magnetic resonance imaging (MRI) is one of the most popular techniques in brain science and is important for understanding brain function and neuropsychiatric disorders. However, the processing and analysis of MRI is not a trivial task with lots of challenges. Recently, deep learning has shown superior performance over traditional machine learning approaches in image analysis. In this survey, we give a brief review of the recent popular deep learning approaches and their applications in brain MRI analysis. Furthermore, popular brain MRI databases and deep learning tools are also introduced. The strength and weaknesses of different approaches are addressed, and challenges as well as future directions are also discussed.

The accumulation of vast amounts of multimodal data for the human brain, in both normal and disease conditions, has provided unprecedented opportunities for understanding why and how brain disorders arise. Compared with traditional analyses of single datasets, the integration of multimodal datasets covering different types of data (i.e., genomics, transcriptomics, imaging, etc.) has shed light on the mechanisms underlying brain disorders in greater detail across both the microscopic and macroscopic levels. In this review, we first briefly introduce the popular large datasets for the brain. Then, we discuss in detail how integration of multimodal human brain datasets can reveal the genetic predispositions and the abnormal molecular pathways of brain disorders. Finally, we present an outlook on how future data integration efforts may advance the diagnosis and treatment of brain disorders.

Polarity regulation is the biggest obstacle to the application of two-dimensional materials in logic circuits. Here, we demonstrate an innocuous doping strategy for modulating the polarity of WSe2 field-effect transistors (FETs). The substoichiometric indium oxide (InO x ) was employed to realize the n-type WSe2 FETs. In stark contrast to others reporting the reduction of electron-dominant current with n-type metal/oxide doping, the InO x -doped strategy demonstrated herein facilitates superior electron-dominant current, which can be attributed to the van der Waals interface between InO x and WSe2. Furthermore, the InO x -doped n-type FET was connected with the undoped p-type FET to construct an inverter, which exhibited an ultrahigh Gain exceeding 120 with a full width at half of the maximum gain of only 30 mV and total noise margin around 80%. The damage-free doping strategy allowed the integration of complementary WSe2 FETs with impressive performance, thereby paving the way for practical applications in WSe2 integrated circuits.

Increasing number of resistant bacteria have emerged with the overuse of antibiotics, which indicates that the bacterial infection has become a global challenge. Furthermore, the pollution of antibiotics to the environment has become a serious threat to public health. It is known that toxins produced by bacteria are the main cause of bacterial infections. Photothermal therapy is an effective antibacterial approach. However, the photothermal reagents cannot eliminate bacterial toxins, and even some anti-bacterial materials are toxic. Here, we synthesized a biomimetic recycled nanoparticle, red blood cell (RBC) membrane-coated Fe3O4 nanoparticles (RBC@Fe3O4), as an antibacterial agent. The RBC@Fe3O4 nanoparticles act as nano-sponges to trap toxins and then kill them all with a photothermal effect. We can describe this process simply as a battle between two armies. Our strategy is to disarm the "enemy" so that we can easily kill the "enemy" who has no power, which results in enhancing the bactericidal efficacy. The toxin of methicillin-resistant Staphylococcus aureus (MRSA) was absorbed by RBC@Fe3O4in vitro. In addition, in vivo studies proved that the RBC@Fe3O4 nanoparticles confer obvious survival benefits against toxin-induced lethality by absorbing the toxin of MRSA. Furthermore, using a mouse model of MRSA wound infection, the RBC@Fe3O4 nanoparticles with laser irradiation were found to have a superior wound-healing effect. Simultaneously, the RBC@Fe3O4 nanoparticles could be recycled in a simple way without affecting the bactericidal efficacy. The highly biocompatible and recyclable RBC@Fe3O4 biomimetic nanoparticles based on photothermal therapy and bacterial toxin adsorption strategy are promising for treating bacterial infections.

This study was designed to investigate the influence of roasting (150 °C for 0-60 min) on key volatile compounds, sensory evaluation, free amino acids, sugars, and Maillard reaction products (MRPs) of five rapeseed varieties and their oils. During the roasting process, key volatile MRPs of fragrant rapeseed oils (FROs) that increased obviously in concentration were mainly pyrazines. After 60 min of roasting, the stronger nutty-like odor in oil from QH was possibly caused by the high levels of 2,5-dimethylpyrazine (21.72 mg/kg) and 3-ethyl-2,5-dimethylpyrazine (5.06 mg/kg). The 5-hydroxymethylfurfural contents and browning indices increased significantly, whereas reducing sugar and free amino acid contents decreased significantly (p0.05). This suggested the extent of the Maillard reaction increased with roasting time. Furthermore, the results of Maillard reaction model system demonstrated glycine, lysine, and histidine could react with glucose to generate 2,5-dimethylpyrazine. Hence, 2,5-dimethylpyrazine is identified as one of the important aroma-active MRPs for FRO.

Planar-type perovskite solar cells (p-PSCs) based on SnO2 have garnered further attention due to their simple and low-temperature fabrication. Improving the critical properties of the electron transport layer (ETL) is an effective way to enhance the performance of p-PSC devices. Here, a brand-new method is developed to relieve the contact recombination caused by the rough fluorine-doped tin oxide (FTO) surface and further boosts the electrical concentration of the ETL. A SnO2-ethylene diamine tetraacetic acid (EDTA) acylamide compound (SEAC) with hydrogen bond-induced adjustable cluster size is reported for the first time. The rational choice of the SEAC cluster size is the key for obtaining the smooth interfacial morphology of the ETL on the rugged FTO substrate. In addition, the energy band gap decreases with the increasing cluster size, and consequently, results in improved electrical conductivity of the SEAC. The upshifted Fermi energy level leads to higher electron concentration, which is an important physical quantity of the ETL. The PSC devices based on the optimized SEAC achieve an improved power conversion efficiency of 21.29% with negligible J-V hysteresis due to significantly enhanced electron transport and reduced contact charge recombination at the ETL/perovskite interface. In general, this paper comes up with a unique strategy to improve the quality of the SnO2-based ETL.

The role of endogenous serotonin (5-HT) in gastrointestinal motility is still highly controversial. Although electrochemical techniques allow for direct and real-time recording of biomolecules, the dynamic monitoring of 5-HT release from elastic and tubular intestine during motor reflexes remains a great challenge because of the specific peristalsis patterns and inevitable passivation of the sensing interface. A stretchable sensor with antifouling and decontamination properties was assembled from gold nanotubes, titanium dioxide nanoparticles, and carbon nanotubes. The sandwich-like structure endowed the sensor with satisfying mechanical stability and electrochemical performance, high resistance against physical adsorption, and superior efficiency in the photodegradation of biofouling molecules. Insertion of the sensor into the lumen of rat ileum (the last section of the small intestine) successfully mimics intestinal peristalsis, and simultaneous real-time monitoring of distension-evoked 5-HT release was possible for the first time. Our results unambiguously reveal that mechanical distension of the intestine induces endogenous 5-HT overflow, and 5-HT level is closely associated with the physiological or pathological states of the intestine.

Hole-transport material-free (HTM-free) perovskite solar cells (PSCs) have the advantages of low manufacturing cost and excellent stability, however, the power conversion efficiencies (PCEs) of these PSCs are relatively low due to the high recombination rate at charge transport interface contacts. Herein, a novel bilayer electron-transport scaffold of SiO2/NaYF4:Yb,Er@SiO2 modified TiO2 nanorods was designed to improve the performance of HTM-free PSCs. Facilitated by the 1D nanorods structure of underneath TiO2 scaffold, photogenerated charges can be quickly transported out of perovskite film with reduced recombination, and the NaYF4:Yb,Er@SiO2 insulating capping layer can further inhibit the charge recombination by removing charge shorting pathways caused by the tangle of TiO2 nanorods with carbon back contact. Moreover, NaYF4:Yb,Er can upconvert near-infrared light into visible region that can be directly used by perovskite materials to improve the current density of corresponding PSCs. Our PSCs have an average PCE of 14.01 ± 0.53%. We demonstrated that up-conversion of light at 980 nm was possible but up-conversion made no statistical improvement in performance.

This study aims to investigate the effect of glucosinolate (GSL) degradation on the volatile odor of rapeseed oil (RO) during roasting. Volatile compounds of RO and individual GSL contents in the seeds were identified and measured during roasting, separately. Total GSL content decreased by 30.47-84.44%. Nitriles were the key volatile compounds that were negatively correlated with GSLs for all samples. Results indicate that GSL degradation significantly affects the volatile odor of RO and tends to produce low-carbon nitriles. Furthermore, the thermal degradation pathways of GSLs were explored according to the structure of individual GSLs and nitriles. These results provide information for the thermal degradation pathways of GSLs and the formation mechanism of nitriles during seed roasting.

Organic single crystals have great potential in optoelectronic devices owing to their grain-boundary free nature and long exciton diffusion length. In this report, an anthracene linked benzo[b]benzo[4,5]thieno[2,3-d]thiophene semiconductor, 2-An-BTBT was designed and synthesized. Belt like organic single crystals based on 2-An-BTBT were grown via physical vapor transport method. Using an ultrathin wire as the shadow mask, organic field effect transistor (OFET) with a channel length of around 15 μm was fabricated and the highest mobility of 0.9 cm2V−1s−1 and average mobility of 0.58 cm2/V were obtained. Furthermore, photo-response characteristics of the 2-An-BTBT based device were also investigated. Photo-response of as high as 7136 AW-1 was achieved via 17.7 μW/cm2 @380 nm mono wavelength light illumination which is ascribed to the long exciton diffusion length of organic single crystal and ultra-short channel length of the fabricated OFET. Stable switching behavior with rising time and decline time of several seconds is attained which indicates the existence of shallow traps at the insulator/semiconductor interface.

As the scaling of silicon-based field-effect transistors has approached its physical limits, the search for alternative channel materials for future logic devices has attracted much attention. The discovery of graphene has unveiled another material family with layered structures called two-dimensional (2D) materials. Black phosphorus (BP), the most stable allotrope of phosphorus, was introduced as a new type of 2D material in 2014. Thanks to its high mobility, in-plane anisotropy and direct band gap, BP is considered to be a promising candidate for next-generation electronic and optoelectronic devices. Numerous studies have demonstrated the beneficial effects of introducing BP for device architectures. Herein, we present a review outlining recent progress towards high performance BP-based transistors. This review starts with the fundamental properties of BP, including its crystal structure, bandgap, and direct current (DC) and radio-frequency (RF) characteristics, followed by a detailed description of the modulation and application of those properties, involving anisotropy, functionalization and superlattices. Furthermore, we also discuss device design for high-performance transistors, with particular emphasis on interface engineering and device stability. Finally, we offer our perspective on the future of BP electronics, aiming to benefit colleagues who are interested in this exciting research field.

Immunomagnetic micro/nanoparticles (IMNs) have been widely used to isolate rare circulating tumor cells (CTCs) from blood samples for early diagnosis of cancers. However, when entering into biofluids, IMNs nonspecifically adsorb biomolecules and the in situ formed biomolecule corona covers IMN surface ligands and weakens the targeting capabilities of IMNs. In this work, we demonstrated that by surface coating of IMNs with red blood cell (RBC)-derived vesicles, the obtained biomimetic particles (RBC-IMNs) basically adsorb no biomolecules and maintain the CTC targeting ability when exposed to plasma. Compared to IMNs, RBC-IMNs exhibited an excellent cell isolation efficiency in spiked blood samples, which was improved to 95.71% from 60.22%. Furthermore, by using RBC-IMNs, we successfully isolated CTCs in 28 out of 30 prostate cancer patient blood samples and further showed the robustness of RBC-IMNs in downstream cell sequencing. The work presented here provides a new insight into developing targeted nanomaterials for biological and medical applications.

The electrochemical performance of lithium ion batteries depend largely on the structural properties of electrode materials. In this work, we propose an approach to synthesize lithium-rich layered oxides (LLOs) materials using a manganese dioxide (MnO2) template strategy, which could control the structure and particle size of final products via choosing different MnO2 templates. Through precisely optimizing, we successfully prepare cross-linked nanorods (CLNs) and agglomerate microrods (AMs) Li1.2Ni0.15Co0.1Mn0.55O2 cathode materials by using carbon-decorated MnO2 nanowires and MnO2 nanorods as templates, respectively. The lithium ion battery based on the CLNs exhibits excellent performance, delivering a high capacity of 286.2 mAh g−1 at 0.1 C and 237.5 mAh g−1 at 1 C. In addition, the device remains 98% and 89% of its initial capacity after 50 cycles at 0.1 C and 100 cycles at 1 C, respectively. The remarkable electrochemical performance can be mainly attributed to the cross-linked nanorods structure which can provide relatively shorter lithium ion diffusion length, larger reaction surface and more internal cavity. This universal structure engineering strategy may shed light on new material structures for high performance lithium-rich layered oxide cathode materials.

Surface passivation of the electron transport layer in perovskite solar cells has been proven to be one crucial strategy to improve the power conversion efficiency. In this study, we introduce rutile phase titania shell to passivate anatase TiO2 scaffold, forming anatase@rutile mixed-phase TiO2 scaffold in hole-conductor-free carbon based perovskite solar cells. Anatase@rutile mixed phase TiO2 films exhibit higher conductivity, faster charge extraction, lower trap density and suppressed charge recombination at the interface of TiO2/perovskite films in the modified devices as well, achieving a champion power conversion efficiency of 15.21% for carbon based perovskite solar cells. More importantly, benefiting from the stable and better ultraviolet light filtration properties of rutile phase TiO2, our devices exhibit excellent stability maintaining 92% of their initial efficiency after 200 days storage in ambient air, highlighting their merits as a potential competitor for future industrial photovoltaics.

Nontoxic tin-based perovskite solar cells (Sn-PSCs) as a promising alternative to toxic Pb-PSCs have drawn great attention in recent years for their environmental friendliness and unique optoelectronic properties. However, both the efficiency and long-term stability of Sn-PSCs are considerably inferior to those of Pb-based ones. One of the main reasons is the difficulty in obtaining high-quality Sn-perovskite films due to the rapid crystallization of Sn-perovskites, which also results in poor device reproducibility. Here, we report a novel cation exchange strategy to prepare high-quality formamidinium tin triiodide (FASnI3) perovskite films with a better controlled crystallization process and improved reproducibility, which allows easy access to smooth and pinhole-free perovskite films with oriented crystal growth, enlarged grain size, and reduced trap-state density. The corresponding Sn-PSCs show excellent photovoltaic performance with a champion efficiency of 9.11%, comparable to the best results reported for FASnI3-PSCs, and the devices also demonstrate outstanding long-term stability without encapsulation. Our results offer a practical strategy for fabricating Sn-PSCs with superb performance and stability.

Prenatal diagnostics holds great significance for pregnant women desiring healthy babies. Fetal nucleated red blood cells (fNRBCs), bearing the complete genome of the fetus, have been regarded as an important biomarker for noninvasive prenatal diagnostics (NIPD). The high-performance detection and enrichment of fNRBCs from maternal blood, especially during early pregnancy, is urgently needed for NIPD, which, unfortunately, remains a big challenge for early-pregnancy fNRBC isolation. In this study, we developed an innovative platform based on silica microbeads for fNRBC isolation and release in early pregnancy. Microbeads were coated with self-assembled MnO2 nanoparticles (SiO2@MnO2) and then modified with a specific antibody. Benefiting from the three-dimensional nanostructure of the MnO2 nanoparticles, the isolation efficiency of the fNRBCs was enhanced. Subsequently, fNRBCs were released via dissolving the MnO2–nanoparticle coating using oxalic acid. We successfully isolated fNRBCs from the maternal peripheral blood samples of 20 pregnant women in the early pregnancy period, ranging from 41 to 62 gestational days. More importantly, the fetal origin of isolated cells was confirmed via fluorescent in situ hybridization and short tandem repeat analysis. This platform based on SiO2@MnO2 microbeads has verified the existence of fNRBCs in early-pregnancy maternal blood and is a promising approach for NIPD in early pregnancy.

The human cerebral cortex undergoes profound structural and functional dynamic variations across the lifespan, whereas the underlying molecular mechanisms remain unclear. Here, with a novel method transcriptome-connectome correlation analysis (TCA), which integrates the brain functional magnetic resonance images and region-specific transcriptomes, we identify age-specific cortex (ASC) gene signatures for adolescence, early adulthood and late adulthood. The ASC gene signatures are significantly correlated with the cortical thickness (P-value Availability: All scripts are written in R. Scripts for the TCA method and related statistics result can be freely accessed at https://github.com/Soulnature/TCA. Additional data related to this paper may be requested from the authors.

Li metal is considered a highly desirable anode for next-generation high-energy-density rechargeable lithium batteries. However, irregular Li dendrite formation and infinite relative volume changes prevent the commercial adoption of Li-metal anodes. Here, electrophoretic deposition of black phosphorus (BP) on commercial Cu foam (BP@Cu foam) is reported to regulate Li nucleation for the first time. First-principles calculations reveal that the unique two-dimensional (2D) structure of BP is beneficial to Li intercalation and propagation. Compared with the random Li nucleation and growth on bare Cu foam, Li ions are preferably confined into the BP layers, which induces uniform Li nucleation at the early stage of the Li deposition and guides the following lateral Li growth on BP@Cu foam. In addition, the three-dimensional (3D) porous and conductive framework of Cu foams further mitigate the volume change and dissipate the current density. Attributing to these merits, the BP@Cu foam exhibits significantly enhanced Coulombic efficiency and cycling stability compared with bare Cu foam. In the full-cell configuration paired with a Li4Ti5O12 or LiFePO4 cathode, the BP@Cu foam also boosts the battery performances. This work provides new insights into the development of BP and other elaborate 2D materials for achieving dendrite-free Li-metal anodes.

Being easy, safe and reliable, non-invasive prenatal diagnosis (NIPD) has been greatly pursued in recent years. Holding the complete genetic information of the fetus, fetal nucleated red blood cells (fNRBCs) are viewed as a suitable target for NIPD application. However, effective separating fNRBCs from maternal peripheral blood for clinic use still faces great challenges, given that fNRBCs are extremely rare in maternal blood circulation. Here, by combining the high-throughput inertial microfluidic chip with multifunctional microspheres as size amplification, we develop a novel method to isolate fNRBCs with high performance. To enlarge the size difference between fNRBCs and normal blood cells, we use the gelatin coated microspheres to capture fNRBCs with anti-CD147 as specific recognizer at first. The size difference between fNRBCs captured by the microspheres and normal blood cells makes it easy to purify the captured fNRBCs through the spiral microfluidic chip. Finally, the purified fNRBCs are mildly released from the microspheres by enzymatically degrading the gelatin coating. Cell capture efficiency about 81%, high purity of 83%, as well as cell release viability over 80% were achieved using spiked samples by this approach. Additionally, fNRBCs were successfully detected from peripheral blood of pregnant women with an average of 24 fNRBCs per mL, suggesting the great potential of this method for clinical non-invasive prenatal diagnosis.

The human cerebral cortex undergoes profound structural and functional dynamic variations across the lifespan, whereas the underlying molecular mechanisms remain unclear. Here, with a novel method TCA (Transcriptome-connectome Correlation Analysis), which integrates the brain functional MR magnetic resonance images and region-specific transcriptomes, we identify age-specific cortex (ASC) gene signatures for adolescence, early adulthood, and late adulthood. The ASC gene signatures are significantly correlated with the cortical thickness (P-value P-value ARNT2 and its target gene ETF1 involved in Schizophrenia. We further validate the ASC gene signatures with published gene sets associated with the adult cortex, and confirm the robustness of TCA on other brain image datasets.

Root hair elongation relies on polarized cell expansion at the growing tip. As a major osmotically active ion, potassium is expected to be continuously assimilated to maintain cell turgor during hair tip growth. However, due to the lack of practicable detection methods, the dynamics and physiological role of K+ in hair growth are still unclear. In this report, we apply the small-molecule fluorescent K+ sensor NK3 in Arabidopsis root hairs for the first time. By employing NK3, oscillating cytoplasmic K+ dynamics can be resolved at the tip of growing root hairs, similar to the growth oscillation pattern. Cross-correlation analysis indicates that K+ oscillation leads the growth oscillations by approximately 1.5 s. Artificially increasing cytoplasmic K+ level showed no significant influence on hair growth rate, but led to the formation of swelling structures at the tip, an increase of cytosolic Ca2+ level and microfilament depolymerization, implying the involvement of antagonistic regulatory factors (e.g., Ca2+ signaling) in the causality between cytoplasmic K+ and hair growth. These results suggest that, in each round of oscillating root hair elongation, the oscillatory cell expansion accelerates on the heels of cytosolic K+ increment, and decelerates with the activation of antagonistic regulators, thus forming a negative feedback loop which ensures the normal growth of root hairs.

Although anti-PD-1 immunotherapy is widely used to treat melanoma, its efficacy still has to be improved. In this work, we present a therapeutic method that combines immunotherapy and starvation therapy to achieve better antitumor efficacy. We designed the CMSN-GOx method, in which mesoporous silica nanoparticles (MSN) are loaded with glucose oxidase (GOx) and then encapsulate the surfaces of cancer cell membranes to realize starvation therapy. By functionalizing the MSN's biomimetic surfaces, we can synthesize nanoparticles that can escape the host immune system and homologous target. These attributes enable the nanoparticles to have improved cancer targeting ability and enrichment in tumor tissues. Our synthetic CMSN-GOx complex can ablate tumors and induce dendritic cell maturity to stimulate an antitumor immune response. We performed an in vivo analysis of these nanoparticles and determined that our combined therapy CMSN-GOx plus PD-1 exhibits a better antitumor therapeutic effect than therapies using CMSN-GOx or PD-1 alone. Additionally, we used the positron emission tomography imaging to measuring the level of glucose metabolism in tumor tissues, for which we investigate the effect with the cancer therapy in vivo.

Research on circulating tumor cells (CTCs) is of great significance in cancer diagnosis, prognosis and even the development of personalized therapy. Here, we present a simple and transparent acoustofluidic device for CTC separation in a label-free and non-invasive manner, instead of traditional acoustic devices based on silicon substrates, which are not only expensive, but also not conducive to optical visualization. The device is based on cheaper glass fabrication and integrated with a 36°Y-rotated cut lithium niobate single crystal (36° LNO) coated indium tin oxide (ITO) acoustic actuator instead of piezoceramics. It could greatly reduce the generation of heat when the signal is excited by utilizing the thickness vibration mode of the 36° LNO single crystal material because of its super-linear performance. Moreover, pre-aligning the particles in the sample inlet in a two-dimensional (2D) mode served to improve the separation efficiency of the device. It was proved that the separation efficiency of polystyrene particles was 97.1 ± 1.0%. The average separation efficiency of cancer cell lines (MCF7 and HeLa) mixed with white bloods cells was about 91.5 ± 4.5%. Owing to the excellent light transmittance of this acoustofluidic device, it has great potential for application to related optical techniques for cell detection while simultaneously separating cells relying on an acoustic field.

Non-adherent cells play key roles in various biological processes. Studies on this type of cell, especially at single-cell resolution, help reveal molecular mechanisms underlying many biological and pathological processes. The emerging microfluidics technology has developed effective methods for analyzing cells. However, it remains challenging to treat and monitor single live non-adherent cells in an in situ, long-term, and real-time manner. Herein, a microfluidic platform was set up to generate and anchor cell-laden water-in-oil-in-water (W/O/W) double emulsions (DEs) to investigate these cells. Within the device, W/O/W DEs encapsulating non-adherent cells were generated through two adjacent flow-focusing structures and subsequently anchored in an array of microchambers. These droplets maintained the W/O/W structure and the anchorage status in the continuous perfusion fluid for at least one week. The mass transfer of different molecules with suitable molecular weights and partition coefficients between the interior and exterior of W/O/W DEs could be regulated by perfusion fluid flow rates. These features endow this platform with potential to continuously supply encapsulated non-adherent cells with nutrients or small-molecule stimuli/drugs through fluid perfusion. Meanwhile, the confinement of cells in the anchored DEs favored long-term monitoring of cellular dynamic behaviors and responses. As a proof of concept, fluorescein diacetate (FDA) was employed to visualize the cellular uptake and biochemical metabolism of TF-1 human erythroleukemia cells. We believe that this W/O/W DE anchorage and perfusion platform would benefit single-cell-level studies as well as small-molecule drug discovery requiring live non-adherent cells.

Cell-free DNA has been widely used in non-invasive prenatal diagnostics (NIPD) nowadays. Compared to these incomplete and multi-source DNA fragments, fetal nucleated red blood cells (fNRBCs), once as an aided biomarker to monitor potential fetal pathological conditions, have re-attracted research interest in NIPD because of their definite fetal source and the total genetic information contained in the nuclei. Isolating these fetal cells from maternal peripheral blood and subsequent cell-based bio-analysis make maximal genetic diagnosis possible, while causing minimal harm to the fetus or its mother. In this paper, an affinity microchip is reported which uses hydroxyapatite/chitosan nanoparticles as well as immuno-agent anti-CD147 to effectively isolate fNRBCs from maternal peripheral blood, and on-chip biomedical analysis was demonstrated as a proof of concept for NIPD based on fNRBCs. Tens of fNRBCs can be isolated from 1 mL of peripheral blood (almost 25 mL-1 in average) from normal pregnant women (from the 10th to 30th gestational week). The diagnostic application of fNRBCs for fetal chromosome disorders (Trisomy 13 and 21) was also demonstrated. Our method offers effective isolation and accurate analysis of fNRBCs to implement comprehensive NIPD and to enhance insights into fetal cell development.

Multi-junction all-perovskite tandem solar cells are a promising choice for next-generation solar cells with high efficiency and low fabrication cost. However, the lack of high-quality low-bandgap perovskite absorber layers seriously hampers the development of efficient and stable two-terminal monolithic all-perovskite tandem solar cells. Here, we report a bulk-passivation strategy via incorporation of chlorine, to enlarge grains and reduce electronic disorder in mixed tin–lead low-bandgap (~1.25 eV) perovskite absorber layers. This enables the fabrication of efficient low-bandgap perovskite solar cells using thick absorber layers (~750 nm), which is a requisite for efficient tandem solar cells. Such improvement enables the fabrication of two-terminal all-perovskite tandem solar cells with a champion power conversion efficiency of 21% and steady-state efficiency of 20.7%. The efficiency is retained to 85% of its initial performance after 80 h of operation under continuous illumination. Two-terminal monolithic all-perovskite tandem solar cells are attractive due to their flexible nature and low-cost fabrication. Here the authors develop a process to obtain high-quality Sn–Pb perovskite thin films by incorporating chlorine. Such layers are employed to fabricate 20.7%-efficient tandem cells with 80 h operational stability.

Controllable three-dimensional villose titanium dioxide architectures grown on carbon textiles are fabricated by a facile one-step in-situ hydrothermal method at low temperatures. It has in fact been proven to be an effective method to reduce self-aggregation and promote lithium-ion intercalate/extract via building 3D architectures based on 2D conductive materials. More importantly, the freestanding electrodes without any addition of conductive agents and polymeric binders reveal significant improvement in high-rate capacity and cycling performance.

Herein, we demonstrate a sustainable strategy for scalable production of α-Fe2O3 nanocrystals on flexible carbon textiles via controllable chemical bath deposition process. The assembly of α-Fe2O3 nanocrystals is densely anchored onto the carbon textiles, and the temperature-dependent mass loading and crystal size of α-Fe2O3 are systematically investigated. As an integrated electrode for lithium-ion batteries, the optimized Fe2O3@CTs with ultrathin three-dimensional interconnected porous architectures achieves significantly enhanced cycling performance and rate capability attributing to the improved stability, electronic interconnection, and shortened solid state diffusion pathway for Li+ ions/electrons. After the reactivation of the precursor, the Li-ion batteries based on the recycled Fe2O3@CTs exhibits electrochemical performance with no decay compared to that of the devices based on the fresh products. This sustainable methodology, considering material abundance, eco-efficiency, synthetic approach and scalability, is of crucial importance to both academy and industry for achieving high-performance lithium-ion batteries.

Perovskite nanocrystals (PNCs) have emerged as advanced materials for various applications. Herein, we developed oxygen insensitive PNCs in polymer matrices and applied them as internal reference to achieve ratiometric sensing for oxygen. Significant emission color changes from orange under nitrogen to green under oxygen were observed. Further micro-patterned sensors were prepared by micro/nano-imprint technology. Results showed that all these micro-structures increased sensors’ sensitivity, however, affected sensors response time significantly. The film with pinholes slowed down the response times; the films with pillars shorted the response time. Therefore, for the first time we prepared new PNCs-based ratiometric gaseous oxygen sensing films and further prepared micro-structured sensors. This study may broaden the applications of perovskite materials and also oxygen sensors.

Exploring earth-abundant and cost-effective catalysts with high activity and stability for a hydrogen evolution reaction (HER) is of great importance to practical applications of alkaline water electrolysis. Here, we report on A-site Ba2+-deficiency doping as an effective strategy to enhance the electrochemical activity of BaCo0.4Fe0.4Zr0.1Y0.1O3−δ for HER, which is related to the formation of oxygen vacancies around active Co/Fe ions. By comparison with the benchmarking Ba0.5Sr0.5Co0.8Fe0.2O3−δ, one of the most spotlighted perovskite oxides, the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3−δ oxide has lower overpotential and smaller Tafel slope. Furthermore, the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3−δ catalyst is ultrastable in an alkaline solution. The enhanced HER performance originated from the increased active atoms adjacent to oxygen vacancies on the surface of the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3−δ catalyst induced by Ba2+-deficiency doping. The low-coordinated active atoms and adjacent oxygen ions may play the role of heterojunctions that synergistically facilitate the Volmer process and thus render stimulated HER catalytic activity. The preliminary results suggest that Ba2+-deficiency doping is a feasible method to tailor the physical and electrochemical properties of perovskite, and that Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3−δ is a potential catalyst for HER.

Assays toward single-cell analysis have attracted the attention in biological and biomedical researches to reveal cellular mechanisms as well as heterogeneity. Yet nowadays microfluidic devices for single-cell analysis have several drawbacks: some would cause cell damage due to the hydraulic forces directly acting on cells, while others could not implement biological assays since they could not immobilize cells while manipulating the reagents at the same time. In this work, we presented a two-layer pneumatic valve-based platform to implement cell immobilization and treatment on-chip simultaneously, and cells after treatment could be collected non-destructively for further analysis. Target cells could be encapsulated in sodium alginate droplets which solidified into hydrogel when reacted with Ca2+ . The size of hydrogel beads could be precisely controlled by modulating flow rates of continuous/disperse phases. While regulating fluid resistance between the main channel and passages by the integrated pneumatic valves, on-chip capture and release of hydrogel beads was implemented. As a proof of concept for on-chip single-cell treatments, we showed cellular live/dead staining based on our devices. This method would have potential in single cell manipulation for biochemical cellular assays.

The efficient capture and high-activity release of circulating tumor cells (CTCs) remain a challenge for the microfluidic chip. We have fabricated a dual-mode gelatin-polydimethylsiloxane (PDMS) microfluidic chip with a sawtooth columnar microstructure of channels that can capture the efficiency of this substrate up to 95%. Increasing the gelatin temperature to physiologic temperature (37 °C) with a baking table facilitates the overall release of CTCs. With melting of the gelatin substrate, the cells will enter into the PDMS corresponding channel; however, the released cells will be wrapped by a layer of gelatin, which may affect further proliferation of the cells. Another way to release CTCs is to use a matrix metalloproteinase-9 (MMP-9) enzyme to dissolve the gelatin and release the tumor cells with high cellular viability. This dual-mode microfluidic chip has been applied successfully to capturing and releasing CTCs, thus serving as a powerful clinical tool that facilitates the subsequent bioanalysis of CTCs for clinical and biological research.

Although great efforts have been devoted to enhancing the efficiency and stability of perovskite solar cells (PSCs), the performance of PSCs has been far lower than anticipated. Interface engineering is helpful for obtaining high efficiency and stability through control of the interfacial charge transfer in PSCs. This paper demonstrates that the efficiency and stability of PSCs can be enhanced by introducing stable α-CsPbI3 quantum dots (QDs) as an interface layer between the perovskite film and the hole transport material (HTM) layer. By synergistically controlling the valence band position (VBP) of the perovskite and the interface layer, an interface engineering strategy was successfully used to increase the efficiency of hole transfer from the perovskite to the HTM layer, resulting in the power conversion efficiency increasing from 15.17 to 18.56%. In addition, the enhancement of the stability of PSCs can be attributed to coating inorganic CsPbI3 QDs onto the perovskite layer, which have a high moisture stability and result in long-term stability of the PSCs in ambient air.

Sodium tetrahydroborate (NaBH4) and dodecahydro-closo-dodecaborate (Na2B12H12) are both important inorganic compounds presenting multiple applications. Nevertheless, multistep and complicated conditions are usually demanded for their synthesis. In order to simplify the synthesis processes, we design a novel and facile solvent-free method for synthesizing NaBH4 or Na2B12H12 from NaNH2 and B10H14. The product of either NaBH4 or Na2B12H12 is manipulable by simply adjusting the ratio of NaNH2 to B10H14. The reaction equations of synthesizing NaBH4 and Na2B12H12 are proposed and verified, and the reaction pathways are elucidated. The findings here supply new insight to synthesize metal dodecaborates using the strategy of equal electron body for the first time and may shed light on synthesis of small metal B-H compounds from large B-H clusters.

The preparation of high-quality perovskite films with low defect density and long carrier lifetime is a precondition for achieving high-efficiency perovskite solar cells (PSCs). In this work, we successfully incorporated Y3+ ions into perovskite films to enhance the photovoltaic performance of hole-transport-layer-free (HTL-free) carbon-based MAPbBr3 PSCs in ambient atmosphere. The perovskite films exhibit better crystallinity, lower trap density, and longer carrier lifetime after the introduction of Y3+ ions. By optimizing the doping dosage, a maximal power conversion efficiency (PCE) of 8.313% (open-circuit voltage (VOC) = 1.562 V) is achieved for MAPb0.98Y0.02Br3 PSCs. Moreover, the unencapsulated device also shows remarkable long-term stability over 80 days under dry condition with 20–30% relative humidity (RH) at 20–25 °C, which even maintains 95% of its initial PCE when stored in harsh environment (80 °C and 40–70% RH) over 72 h.