Relevance and antimicrobial resistance profile of Klebsiella pneumoniae in neonatal sepsis.

BACKGROUND: Newborns are particularly susceptible to infection in hospitals, with neonatal sepsis being the most common infection symptom and the third leading cause of neonatal death. Klebsiella pneumoniae is a gram-negative bacterium of Enterobacteriaceae, which is a common pathogen of neonatal septicemia. In this study, we will analyze and evaluate the current status, clinical characteristics, and drug resistance of Klebsiella pneumoniaesepsis infection in Neonatal Intensive Care Unit (NICU), with the aim of providing effective basis for timely and accurate clinical diagnosis and treatment in clinical practice. METHODS: Statistical analysis was performed on 75 cases of Enterobacteriaceae septicemia in infants admitted to NICU in a special obstetrics and gynecology hospital in Shanghai from January 2020 to June 2022. Based on bacterial identification, isolates were divided into the Klebsiella pneumoniae (KP) group (n = 49) and the non-KP Enterobacteriaceae group (n = 26). The infection, clinical characteristics, and bacterial resistance of the two groups of infected patients were compared. RESULTS: Comparing the clinical characteristics of the two groups, the results showed that most of the subjects in the KP and non-KP groups were premature infants, accounting for 100% and 92.3% of subjects, respectively; late onset was the main disease in both groups, accounting for 93.9% and 80.8% of subjects, respectively. All patients received Peripherally Inserted Central Catheter(PICC). The levels of pro calcitonin and CRP (C-reactive protein) were significantly higher in the KP group compared with those in the non-KP group (p < .05). At the same time, the incidence of thrombocytopenia in the KP group was significantly higher than that in the non-KP group (p < .05). The proportion of antimicrobial drug exposure in the KP group is higher than that in the non-KP group. The drug resistance of the KP group to ceftazidime, ceftriaxone, cefepime, ampicillin/sulbactam, aztreonam, ciprofloxacin and compound sulfamethoxazole was significantly higher than that of the non-KP group, whereas the drug resistance rate to cefotetan, gentamycin and to bramycin was significantly lower than that of the non-KP group, Statistically significant differences (p < .05). 38 cases of Klebsiella pneumoniae producing ESBLs were tested for related resistance genes. The results showed that the main resistance types were SHV and TEM, with detection rates of 60.6% and 28.9%. CONCLUSIONS: This study shows that neonatal sepsis caused by Klebsiella pneumoniae infection has a high incidence and drug resistance in premature and low birth weight infants, and has become a serious public health problem; Clinicians should pay attention to differential diagnosis, Reasonable selection of antibiotics to reduce the generation of drug-resistant bacteria.

A Novel Multifunctional Photonic Film for Colored Passive Daytime Radiative Cooling and Energy Harvesting.

Passive daytime radiative cooling (PDRC) materials with sustainable energy harvesting capability is critical to concurrently reduce traditional cooling energy utilized for thermal comfort and transfer natural clean energies into electricity. Herein, a versatile photonic film (Ecoflex@BTO@UAFL) based on a novel fluorescent luminescence color passive radiative cooling with triboelectric and piezoelectric effect is developed by filling the dielectric BaTiO3 (BTO) nanoparticles and ultraviolet absorption fluorescent luminescence (UAFL) powder into the elastic Ecoflex matrix. Test results demonstrate that the Ecoflex@BTO@UAFL photonic film exhibits a maximum passive radiative cooling effect of ∽10.1 °C in the daytime. Meanwhile, its average temperature drop in the daytime is ~4.48 °C, which is 0.91 °C higher than that of the Ecoflex@BTO photonic film (3.56 °C) due to the addition of UAFL material. Owing to the high dielectric constant and piezoelectric effect of BTO nanoparticles, the maximum power density (0.53 W m-2 , 1 Hz @ 10 N) of the Ecoflex@BTO photonic film-based hybrid nanogenerator is promoted by 70.9% compared to the Ecoflex film-based TENG. This work provides an ingenious strategy for combining PDRC effects with triboelectric and piezoelectric properties, which can spontaneously achieve thermal comfort and energy conservation, offering a new insight into multifunctional energy saving.

The current status of Group B Streptococcus infection in the reproductive tract of late-pregnancy women and its impact on pregnancy outcomes.

OBJECTIVE: Analyze Group B Streptococcus (GBS) infection in late-pregnancy pregnant women in Shanghai, the risk factors of GBS infection, and its impact on pregnancy outcomes, providing guidance for early prevention and treatment in clinical practice. METHODS: We selected 12,132 late-pregnancy pregnant women admitted from January 2022 to December 2022 as the research subjects. Based on the GBS test results of reproductive tract secretion samples from pregnant women, 210 cases of GBS positive pregnant women were randomly selected as the observation group, and 200 cases of GBS negative pregnant women were selected as the control group. The risk factors of infection and the impact on pregnancy outcomes were compared between the two groups. RESULTS: The GBS colonization rate of pregnant women in this study was 6.52%; the incidence of Vaginal delivery and Neonatal infection in GBS positive group was significantly higher than that in GBS negative group (P < 0.05); with Neonatal infection as the dependent variable, and the GBS infection, Vaginal delivery and GDM of the elderly and women in late pregnancy as independent variables, the results showed that GBS infection of women in late pregnancy was an independent risk factor for Neonatal infection. CONCLUSION: Clinical practice should attach great importance to GBS infection in late pregnancy, strengthen GBS screening in late pregnancy, and actively implement the strategy of intrapartum antibiotic intervention (IAP), which is of great significance in reducing the vertical infection rate of maternal and infant GBS and improving the quality of newborn birth.

A Versatile Strategy for Concurrent Passive Daytime Radiative Cooling and Sustainable Energy Harvesting.

Developing versatile systems that can concurrently achieve energy saving and energy generation is critical to accelerate carbon neutrality. However, challenges on designing highly effective, large scale, and multifunctional photonic film hinder the concurrent combination of passive daytime radiative cooling (PDRC) and utilization of sustainable clean energies. Herein, a versatile scalable photonic film (Ecoflex@h-BN) with washable property and excellent mechanical stability is developed by combining the excellent scattering efficiency of the hexagonal boron nitride (h-BN) nanoplates with the high infrared emissivity and ideal triboelectric negative property of the Ecoflex matrix. Strikingly, sufficiently high solar reflectance (0.92) and ideal emissivity (0.97) endow the Ecoflex@h-BN film with subambient cooling effect of ≈9.5 °C at midday during the continuous outdoor measurements. In addition, the PDRC Ecoflex@h-BN film-based triboelectric nanogenerator (PDRC-TENG) exhibits a maximum peak power density of 0.5 W m-2 . By reasonable structure design, the PDRC-TENG accomplishes effective wind energy harvesting and can successfully drive the electronic device. Meanwhile, an on-skin PDRC-TENG is fabricated to harvest human motion energy and monitor moving states. This research provides a novel design of a multifunctional PDRC photonic film, and offers a versatile strategy to realize concurrent PDRC and sustainable energies harvesting.

High Performance Graphene-C60 -Bismuth Telluride-C60 -Graphene Nanometer Thin Film Phototransistor with Adjustable Positive and Negative Responses.

Graphene is a promising candidate for the next-generation infrared array image sensors at room temperature due to its high mobility, tunable energy band, wide band absorption, and compatibility with complementary metal oxide semiconductor process. However, it is difficult to simultaneously obtain ultrafast response time and ultrahigh responsivity, which limits the further improvement of graphene photoconductive devices. Here, a novel graphene/C60 /bismuth telluride/C60 /graphene vertical heterojunction phototransistor is proposed. The response spectral range covers 400-1800 nm; the responsivity peak is 106 A W-1 ; and the peak detection rate and peak response speed reach 1014 Jones and 250 µs, respectively. In addition, the regulation of positive and negative photocurrents at a gate voltage is characterized and the ionization process in impurities of the designed phototransistor at a low temperature is analyzed. Tunable bidirectional response provides a new degree of freedom for phototransistors' signal resolution. The analysis of the dynamic change process of impurity energy level is conducted to improve the device's performance. From the perspective of manufacturing process, the ultrathin phototransistor (20-30 nm) is compatible with functional metasurface to realize wavelength or polarization selection, making it possible to achieve large-scale production of integrated spectrometer or polarization imaging sensor by nanoimprinting process.

In-Situ Chemical Thinning and Surface Doping of Layered Bi2Se3.

As a promising topological insulator, two-dimensional (2D) bismuth selenide (Bi2Se3) attracts extensive research interest. Controllable surface doping of layered Bi2Se3 becomes a crucial issue for the relevant applications. Here, we propose an efficient method for the chemical thinning and surface doping of layered Bi2Se3, forming Se/Bi2Se3 heterostructures with tunable thickness ranging from a few nanometers to hundreds of nanometers. The thickness can be regulated by varying the reaction time and large-size few-layer Bi2Se3 sheets can be obtained. Different from previous liquid-exfoliation methods that require complex reaction process, in-situ and thickness-controllable exfoliation of large-size layered Bi2Se3 can be realized via the developed method. Additionally, the formation of Se nanomeshes coated on the Bi2Se3 sheets remarkably enhance the intensity of Raman vibration peaks, indicating that this method can be used for surface-enhanced Raman scattering. The proposed chemical thinning and surface-doping method is expected to be extended to other bulk-layered materials for high-efficient preparation of 2D heterostructures.

Analysis of Factors Related to Neonatal Infection and Monitoring of Bacterial Drug Resistance.

OBJECTIVE: To study the factors related to neonatal infection, as well as bacterial distribution and drug resistance in neonatal infections, in an obstetrics and gynecology hospital in Shanghai. METHODS: The bacterial culture and drug resistance monitoring results from neonates treated at the hospital from January 2020 to June 2021 were analyzed and compared with the data for children and newborns from the national bacterial resistance surveillance report. RESULTS: Among the 209 bacterial strains isolated from infected neonates, 90 were gram-positive, including the four most common isolates: coagulase-negative Staphylococcus, Staphylococcus aureus, Enterococcus, and Streptococcus agalactiae. The remaining 119 strains were gram-negative and included Klebsiella pneumoniae, Acinetobacter baumannii, and Enterobacter aerogenes. The drug sensitivity results showed that the methicillin-resistant Staphylococcus aureus isolates were sensitive to linezolid, vancomycin, rifampicin, levofloxacin, and gentamicin. All Klebsiella pneumoniaisolates were sensitive to amikacin, ertapenem, imipenem, and gentamicin. These two strains were resistant to other antibiotics to varying degrees. CONCLUSIONS: Understanding the distribution and drug resistance of bacterial pathogens is vital for guiding the rational selection of antibiotics and reducing neonatal mortality and nosocomial infections.

Emerging Long-Range Order from a Freeform Disordered Metasurface.

Recently, disordered metasurfaces have attracted considerable interest due to their potential applications in imaging, holography, and wavefront shaping. However, how to emerge long-range ordered phase distribution in disordered metasurfaces remains an outstanding problem. Here, a general framework is proposed to generate a spatially homogeneous in-plane phase distribution from a disordered metasurface, by engineering disorder parameters together with topology optimization. As a proof-of-concept demonstration, an all-dielectric disordered supercell metasurface with relatively homogeneous in-plane phase fluctuation is designed by disorder parameter engineering, manifesting as polarization conversion-dependent random scattering or unidirectional transmission. Then, a topology optimization approach is utilized to overcome the lattice coupling effect and to further improve the homogeneity of complex electric field fluctuation. In comparison with the initial supercell metasurface, both the phase fluctuation range and the relative efficiency of the topology-optimized freeform metasurface are significantly improved, leading to a long-range ordered electric field distribution. Moreover, three experimental realizations are performed, all of which agree well with the theoretical results. This methodology may inspire more exotic optical phenomena and find more promising applications in disordered metasurfaces and disordered optics.

Breaking the Cut-Off Wavelength Limit of GaTe through Self-Driven Oxygen Intercalation in Air.

Low symmetric two dimensional (2D) semiconductors are of great significance for their potential applications in polarization-sensitive photodetection and quantum information devices. However, their real applications are limited by their photo-detecting wavelength ranges, which are restricted by their fundamental optical bandgaps. Recently, intercalation has been demonstrated to be a powerful strategy to modulate the optical bandgaps of 2D semiconductors. Here, the authors report the self-driven oxygen (O2 ) intercalation induced bandgap reduction from 1.75 to 1.19 eV in gallium telluride (GaTe) in air. This bandgap shrinkage provides the long-wavelength detection threshold above ≈1100 nm for O2 intercalated GaTe (referred to as GaTeO2 ), well beyond the cut-off wavelength at ≈708 nm for pristine GaTe. The GaTeO2 photodetectors have a high photoresponsivity, and highly anisotropic photodetection behavior to even sub-waveband radiation. The dichroic ratio (Imax /Imin ) of photocurrent is about 1.39 and 2.9 for 600 nm and 1100 nm, respectively. This findings demonstrates a broadband photodetector utilizing GaTe after breaking through its bandgap limitation by self-driven O2 intercalation in air and further reveal its photoconductivity anisotropic nature. This provides design strategies of 2D materials-based high-performance broadband photodetectors for the exploration of polarized state information.

Conformal Self-Assembly of Nanospheres for Light-Enhanced Airtightness Monitoring and Room-Temperature Gas Sensing.

The fabrication of conformal nanostructures on microarchitectures is of great significance for diverse applications. Here a facile and universal method was developed for conformal self-assembly of nanospheres on various substrates including convex bumps and concave holes. Hydrophobic microarchitectures could be transferred into superhydrophilic ones using plasma treatment due to the formation of numerous hydroxyl groups. Because of superhydrophilicity, the nanosphere suspension spread on the microarchitectures quickly and conformal self-assembly of nanospheres can be realized. Besides, the feature size of the conformal nanospheres on the substrates could be further regulated by plasma treatment. After transferring two-dimensional tungsten disulfide sheets onto the conformal nanospheres, the periodic nanosphere array was demonstrated to be able to enhance the light harvesting of WS2. Based on this, a light-enhanced room-temperature gas sensor with a fast recovery speed (<35 s) and low detecting limit (500 ppb) was achieved. Moreover, the WS2-covered nanospheres on the microarchitectures were very sensitive to the changes in air pressure due to the formation of suspended sheets on the convex bumps and concave holes. A sensitive photoelectronic pressure sensor that was capable of detecting the airtightness of vacuum devices was developed using the WS2-decorated hierarchical architectures. This work provides a simple method for the fabrication of conformal nanospheres on arbitrary substrates, which is promising for three-dimensional microfabrication of multifunctional hierarchical microarchitectures for diverse applications, such as biomimetic compound eyes, smart wetting surfaces and photonic crystals.

Topology-optimized catenary-like metasurface for wide-angle and high-efficiency deflection: from a discrete to continuous geometric phase.

We investigate the topology optimization of geometric phase metasurfaces for wide-angle and high-efficiency deflection, where adjoint-based multi-object optimization approach is adopted to improve the absolute efficiency while maintaining the polarization conversion characteristic of geometric phase metasurfaces. We show that, for the initially discrete geometric phase metasurfaces with different materials and working wavelengths, the topology shapes gradually evolve from discrete structures to quasi-continuous arrangements with the increment of optimization iteration operations. More importantly, the finally optimized metasurfaces manifest as catenary-like structure, providing significant improvements of absolute efficiency. Furthermore, for the initial structure with catenary distribution, the corresponding optimized metasurface also has a catenary-like topology shape. Our results on the topology-optimized geometric phase metasurfaces reveal that, from the perspective of numerical optimization, the continuous catenary metasurfaces is superior to the discrete geometric phase metasurfaces.

Salvia miltiorrhiza improves type 2 diabetes: A protocol for systematic review and meta-analysis.

BACKGROUND: Diabetes refers to any group of metabolic diseases characterized by high blood sugar and generally thought to be caused by insufficient production of insulin, impaired response to insulin. Globally, patients with type 2 diabetes account for more than 85% of the total diabetic patients, and due to factors, such as obesity, aging, environment and lifestyle, the incidence of diabetes is rising. Salvia miltiorrhiza (SM) is a medicine used to treat diabetes in China. In recent years, it has been reported that SM has the effect of improving type 2 diabetes. However, there is no systematic review of its efficacy and safety yet. Therefore, we propose a systematic review to evaluate the efficacy and safety of SM for T2D. METHODS: Six databases will be searched: China National Knowledge Infrastructure (CNKI), China Biological Medicine (CBM), China Scientific Journals Database (CSJD), Wanfang database, PubMed, and EMBASE. The information is searched from January 2010 to July 2020. Languages are limited to English and Chinese. The primary outcomes include 2 hour plasma glucose, fasting plasma glucose, hemoglobin A1c, homeostasis model assessment of insulin resistance, and fasting plasma insulin. The secondary outcomes include clinical efficacy and adverse events. RESULTS: This systematic review will evaluate the efficacy and safety of Salvia miltiorrhiza in the treatment of type 2 diabetes. CONCLUSION: This systematic review provides evidence as to whether Salvia miltiorrhiza is effective and safe for type 2 diabetes. ETHICS: Ethical approval is not necessary as this protocol is only for systematic review and does not involve in privacy data or an animal experiment. SYSTEMATIC REVIEW REGISTRATION: INPLASY2020110046.

The efficacy of Qigong exercises for nonalcoholic fatty liver disease: A protocol for systematic review and meta-analysis.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in the world that represents an important public health challenge nowadays. Lifestyle changes and exercise can reduce the development of fatty liver. The aim of this systematic review and meta-analysis is to evaluate the treatment efficacy of Qigong for NAFLD. METHODS: A detailed search for articles up to September 2020 will be performed to identify randomized controlled trials for Qigong in NAFLD. The following database will be used: PUBMED, Embase, Web of Science, Cochrane Library, Sino Med, Chinese National Knowledge Infrastructure (CNKI), Chinese Science and Technology Periodicals Database, and Wanfang Databas. Grey literature will be explored and the selection of studies, data extraction and validation will be performed independently by 2 reviewers using predefined selection criteria and quality indicators. Stata V.13.0 and Review manager 5.3 software will be used for data synthesis, sensitivity analysis, subgroup analysis, and risk of bias assessment. We will use the grading of recommendations assessment, development, and evaluation system to assess the quality of evidence. RESULTS: This research will provide a quantitative and standardized assessment of the treatment efficacy of Qigong for NAFLD. CONCLUSION: This systematic review will generate the latest evidence for determining whether Qigong has a positive treatment effect for NAFLD. REGISTRATION NUMBER: INPLASY202090034.

Salvia miltiorrhiza improves Alzheimer's disease: A protocol for systematic review and meta-analysis.

BACKGROUND: Alzheimer's disease (AD) is an age-related neurodegenerative disease that is slowly becoming a global problem. Salvia miltiorrhiza (SM) has a history of thousands of years of use in China. In recent years, SM has been reported to have the effect of improving Alzheimer's disease. However, there is no systematic review of its efficacy and safety yet. Therefore, we propose a systematic review to evaluate the efficacy and safety of SM for AD patients. METHODS: Six databases will be searched: China National Knowledge Infrastructure (CNKI), China Biological Medicine (CBM), China Scientific Journals Database (CSJD), Wanfang database, PubMed, and EMBASE. The information is searched from January 2010 to July 2020. Languages are limited to English and Chinese. The primary outcomes include changes in the Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog) and Activities of Daily Living scale (ADL). Additional outcomes include clinical effective rate and adverse event rate. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system will be used to assess the strength of the evidence. RESULTS: This systematic review will evaluate the efficacy and safety of SM in the treatment of Alzheimer's disease. CONCLUSION: This systematic review provides evidence as to whether SM is effective and safe for Alzheimer's disease patients. SYSTEMATIC REVIEW REGISTRATION: INPLASY202070066.

A protocol for systematic review and meta-analysis of optimizing treatment for malaria.

BACKGROUND: Malaria remains a global health threat for centuries. In recent years, a rising resistance of Plasmodium falciparum to current standard artemisinin-based combination therapies (ACTs) leads to increasing treatment failures and requires for optimized treatment. Here, we intend to make a systematic review and meta-analysis of optimizing treatment for malaria, so as to find a potential optimal treatment. METHODS: We will search electronic databases: the Cochrane Infectious Diseases Group (CIDG) Specialized Register, the Cochrane Central Register of Controlled Trials (CEN-TRAL), PubMed, Embase, Web of Science from their inception to 1 July, 2020. We will also search International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov, and contact with authors when necessary. Two authors will independently collect and select data, and the statistical analyses will be conducted by Revman V.5.3 software. RESULTS: We will evaluate efficacy and safety of modified ACTs for uncomplicate malaria, comparing with standard ACTs in all eligible clinical studies. CONCLUSION: In this study, we will offer clinical evidence for optimizing treatment for malaria. REGISTRATION NUMBER: INPLASY202070115.

The efficacy of Qigong exercises for post-stroke mental disorders and sleep disorders: Protocol for a systematic review and meta-analysis.

BACKGROUND: Post-stroke mental disorders (PSMDs) and post-stroke sleep disorders (PSSDs) are quite common condition in stroke's patients. Qigong has been widely applied as a replaced and useful treatment for PSMDs and PSSDs. However, the exact effects and safety of Qigong have yet be systematically investigated. Our study focused on summary of efficacy and safety of Qigong for the treatment of advanced PSMDs and PSSDs through the systematic analysis and meta-analysis, in order to provide scientific reference for the clinical. METHODS: The protocol followed Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols. Relevant randomized controlled trials were only considered. Search strategy will be performed in 4 English database including Cochrane Library, PubMed, Web of Science, Excerpt Medical Database, 4 Chinese Database including Chinese Biomedical Literature Database, China National Knowledge Infrastructure, China Scientific Journal Database, Wanfang Database, and WHO International Clinical Trials Registry Platform. Papers in English or Chinese published from their inception to 30 June 2020. Study selection and data extraction will be performed independently by 2 investigators. The clinical outcomes including overall Hamilton depression scale, Hamilton anxiety scale, the mental health part of the MOS item short from health survey, Generic Quality of Life Inventory-74, Center for Epidemiologic Studies Depression Scale, Pittsburgh sleep quality index. Based on the Cochrane Assessment tool and Physiotherapy Evidence Database scale, a modified assessment form should be used to evaluate the methodological quality. Review Manager 5.3 was used for data analysis and risk of bias. RESULTS AND CONCLUSION: We provide some more practical and targeted results examine the effect of Qigong exercises for PSMDs and PSSDs in the relative meta-analysis. We find out defects or inadequacies of Qigong in previous studies. The findings of this research will provide more evidence-based guidance in clinical practice and more rigorous study.International Platform of Registered Systematic Review and Meta-Analysis Protocols (INPLASY) registration number: INPLASY202070051.

Tunable anisotropic plasmon response of monolayer GeSe nanoribbon arrays.

Recently, emerging two-dimensional (2D) germanium selenide (GeSe) has drawn lots of attention due to its in-plane anisotropic properties and great potential for optoelectronic applications such as in solar cells. However, methods are still sought to enhance its interaction with light to enable practical applications. Herein, we numerically investigate the localized plasmon response of monolayer GeSe nanoribbon arrays systematically, and the results show that localized surface plasmon polaritons in the far-infrared range with anisotropic behavior can be efficiently excited to enhance the light-matter interaction. We further show that the plasmon response of monolayer GeSe nanoribbons could be tuned effectively through the nanoribbon width, local refractive index, substrate thickness and carrier concentration, pointing out the ways for controlling the localized plasmon response. In the case of monolayer GeSe nanoribbons on a substrate of finite thickness, a Fabry-Pérot-like (FP-like) quantitative model has been proposed to explain the overall spectral response originating from overlapped FP and plasmon modes, and it matches well with the simulation results. All in all, we investigate the plasmon response of the novel 2D GeSe nanoribbons thoroughly for the first time, bringing opportunities for potential applications of novel polarization-dependent optoelectronic devices.

Inversion Symmetry Breaking in Lithium Intercalated Graphitic Materials.

Intercalation is a unique degree of freedom for tuning the physical and chemical properties of two-dimensional (2D) materials, providing an ideal system to study various electronic states (such as superconductivity, ferromagnetism, and charge density waves). Here, we demonstrate the inversion symmetry breaking in lithium (Li)-intercalated ultrathin graphite (about 20-100 graphene layers) by optical second-harmonic generation (SHG). This inversion symmetry breaking is attributed to nanoscale inhomogeneities (i.e., lattice distortion and dislocations) in lithiated graphite. In addition, the efficiency of the SHG signal in an ultrathin graphite flake is widely tunable by the electrochemical lithiation process, and the efficiency of fully lithiated graphite (LiC6) is comparable to that of other noncentrosymmetric 2D crystals. Our results reveal a novel intercalation-induced inversion symmetry breaking effect and open up possibilities for building 2D intercalated-compounds-based nonlinear optical devices.

Thickness-Independent Energy Dissipation in Graphene Electronics.

The energy dissipation issue has become one of the greatest challenges of the modern electronic industry. Incorporating graphene into the electronic devices has been widely accepted as a promising approach to solve this issue, due to its superior carrier mobility and thermal conductivity. Here, using Raman spectroscopy and infrared thermal microscopy, we identify the energy dissipation behavior of graphene device with different thicknesses. Surprisingly, the monolayer graphene device is demonstrated to have a comparable energy dissipation efficiency per unit volume with that of a few-layer graphene device. This has overturned the traditional understanding that the energy dissipation efficiency will reduce with the decrease of functional materials dimensions. Additionally, the energy dissipation speed of the monolayer graphene device is very fast, promising for devices with high operating frequency. Our finding provides a new insight into the energy dissipation issue of two-dimensional materials devices, which will have a global effect on the development of the electronic industry.

Near-Infrared Photoelectric Properties of Multilayer Bi2O2Se Nanofilms.

The near-infrared (NIR) photoelectric properties of multilayer Bi2O2Se nanofilms were systematically studied in this paper. Multilayer Bi2O2Se nanofilms demonstrate a sensitive photo response to NIR, including a high photoresponsivity (~ 101 A/W), a quick response time (~ 30 ms), a high external quantum efficiency (~ 20,300%), and a high detection rate (1.9 × 1010 Jones). These results show that the device based on multilayer Bi2O2Se nanofilms might have great potentials for future applications in ultrafast, highly sensitive NIR optoelectronic devices.