Publications by authors named "Pengfei Qiu"

The recently discovered metal-like room-temperature plasticity in inorganic semiconductors reshapes our knowledge of the physical properties of materials, giving birth to a series of new-concept functional materials. However, current room-temperature plastic inorganic semiconductors are still very rare, and their performance is inferior to that of classic brittle semiconductors. Taking classic bismuth telluride (BiTe)-based thermoelectric semiconductors as an example, we show that antisite defects can lead to high-density, diverse microstructures that substantially affect mechanical properties and thus successfully transform these bulk semiconductors from brittle to plastic, leading to a high figure of merit of up to 1.

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Purpose: It is controversial for the optimal time of breast cancer surgery after COVID-19 infection. Purpose was to assess the risk of postoperative complication in breast cancer patients with COVID-19 infection, in order to select optimal surgery timing after COVID-19 infection.

Methods: Breast cancer patients infected with COVID-19 and performed surgery between December 20th, 2022 to March 20th, 2023 were included in this prospective study (n = 577).

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The low conductivity of many traditional metal-organic-framework (MOF)-based electrode limits their developments in the field of electrochemical energy storage and still of great challenge. The controllable preparation of various kinds of nanomaterials using thiol-functionalized MOF shows great prospects. In this work, a thiol-functionalized metal-organic framework sheet structure (Co-MOF/NF) on nickel foam was successfully prepared by in situ interfacial growth synthesis, which was transformed into its derivatives S-doped β-Co(OH) nanoflowers Co-x/NF (x = 1, 2 and 6) in different concentrations of KOH solutions through ion etching/exchange reaction.

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For breast cancer patients with physical exam node negative but radiological finding node abnormal (cN0/rNa), the NCCN and ASCO guidelines recommend sentinel lymph node biopsy (SLNB) as the first-line axillary staging. However, patients who undergo surgery firstly may be upstaged to pathological II-III status, and these patients happen to be the adaptive population of neoadjuvant therapy (NAT). There is no consensus on the optimal management of cN0/rNa patients.

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Purpose: Targeted axillary dissection (TAD) after neoadjuvant therapy (NAT) includes removing of marked and sentinel lymph nodes (SLNs). The aim was to investigate the optimization of TAD localization techniques after NAT among breast cancer patients.

Methods: From November 2020 to 2022, we prospectively enrolled 107 lymph node-positive breast cancer patients in XX Hospital and received complete cycles of NAT.

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Article Synopsis
  • * Researchers introduced a liquid-phase sintering method using MgCu nano-sintering aid to enhance grain size and improve thermoelectric performance in Mg(Bi, Sb)-based materials.
  • * The resulting polycrystals displayed exceptional electrical transport characteristics and low thermal conductivity, achieving a thermoelectric figure of merit of 1.5 at 500 K and a conversion efficiency of 7.4% under a 207 K temperature difference, making it a promising strategy for practical applications.
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Halide perovskites are of great interest due to their exceptional optical and optoelectronic properties. However, thermal conductivity of many halide perovskites remains unexplored. In this study, an ultralow lattice thermal conductivity κ (0.

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Ductile inorganic thermoelectric (TE) materials open a new approach to develop high-performance flexible TE devices. N-type Ag(S,Se,Te) and p-type AgCu(Se,S,Te) pseudoternary solid solutions are two typical categories of ductile inorganic TE materials reported so far. Comparing with the Ag(S,Se,Te) pseudoternary solid solutions, the phase composition, crystal structure, and physical properties of AgCu(Se,S,Te) pseudoternary solid solutions are more complex, but their relationships are still ambiguous now.

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Mode converters, crucial elements within photonic integrated circuits (PICs) designed for multimode optical transmission and switching systems, present a challenge due to their bulky structures in thin-film lithium niobate (TFLN) integrated platforms, which are incompatible with the compact and efficient nature desired for dense PICs. In this work, we propose TE-TE, TE-TE, and TE-TE mode converters in shallowly etched TFLN, within small footprints. The experimental results show that the insertion loss is 0.

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Cu-based liquid-like thermoelectric materials have garnered tremendous attention due to their inherent ultralow lattice thermal conductivity. However, their practical application is hampered by stability issues under a large current or temperature gradient. It has been reported that introduction of copper vacancies can enhance the chemical stability, whereas the micromechanism behind this macroscopic improvement still remains unknown.

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Article Synopsis
  • Critical phenomena in modern physics involve complex experimental and theoretical challenges, particularly regarding thermoelectric properties during phase transitions.
  • A new quantitative theory has been developed that addresses electrical transports by factoring in band broadening and carrier-soft TO phonon interactions, enhancing understanding of Seebeck coefficient and electrical resistivity.
  • The model’s effectiveness is confirmed by experimental validations, highlighting the potential to improve thermoelectric performance, like achieving a zT of 1.3 at critical points, which opens avenues for future research.
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Searching for new high-performance thermoelectric (TE) materials that are economical and environmentally friendly is an urgent task for TE society, but the advancements are greatly limited by the time-consuming and high cost of the traditional trial-and-error method. The significant progress achieved in the computing hardware, efficient computing methods, advance artificial intelligence algorithms, and rapidly growing material data have brought a paradigm shift in the investigation of TE materials. Many electrical and thermal performance descriptors are proposed and efficient high-throughput (HTP) calculation methods are developed with the purpose to quickly screen new potential TE materials from the material databases.

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Background: Triple-negative breast cancer (TNBC) is associated with a dismal prognosis. Immune checkpoint inhibitors have shown promising antitumor activity in neoadjuvant settings. This single-arm, phase II trial aimed to evaluate the efficacy and safety of camrelizumab plus chemotherapy as the neoadjuvant therapy (NAT) in early TNBC.

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The flexible thermoelectric technique, which can convert heat from the human body to electricity via the Seebeck effect, is expected to provide a peerless solution for the power supply of wearables. The recent discovery of ductile semiconductors has opened a new avenue for flexible thermoelectric technology, but their power factor and figure-of-merit values are still much lower than those of classic thermoelectric materials. Herein, we demonstrate the presence of morphotropic phase boundary in AgSe-AgS pseudobinary compounds.

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The recently discovered plastic/ductile inorganic thermoelectric (TE) materials open a new avenue for the fabrication of high-efficiently flexible TE devices, which can utilize the small temperature difference between human body and environment to generate electricity. However, the maximum power factor (PF) of current plastic/ductile TE materials is usually around or less than 10 µW cm K , much lower than the classic brittle TE materials. In this work, a record-high PF of 18.

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Information security has gained increasing attention in the past decade, leading to the development of advanced materials for anti-counterfeiting, encryption and instantaneous information display. However, it remains challenging to achieve high information security with simple encryption procedures and low-energy stimuli. Herein, a series of strain/temperature-responsive liquid crystal elastomers (LCEs) are developed to achieve dual-modal, multi-level information encryption and real-time, rewritable transient information display.

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Calcium peroxide (CP) is an oxidizing agent that can gradually release hydrogen peroxide (HP) to achieve selective killing of cyanobacteria in water blooms, and reduce the phosphorus content in the water column. Despite the potential of CP for use in cyanobacterial water bloom disposal, there is a lack of research on the mechanism of oxidative damage on cyanobacterial cells by calcium peroxide. Further studies are required to comprehend the underlying scientific principles and potential risks and benefits of applying this approach to cyanobacteria disposal.

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Objective: Internal mammary nodes are important in breast cancer prognosis, but their diagnosis is often missed in clinical practice, leading to inaccurate staging and treatment. We developed a validated nomogram to predict the presence of internal mammary sentinel nodes (IMSN) metastasis.

Methods: A total of 864 sequential IMSN biopsy procedures from a prospective studies database of 1505 cases were used for model development and validation.

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Materials with low thermal conductivity have received significant attention across various research fields, including thermal insulation materials, thermal barrier coatings, and thermoelectric materials. Exploring novel materials with intrinsically low thermal conductivity and investigating their phonon transport properties, chemical bonding, and atomic coordination are crucial. In this study, a novel ternary sulfide is successfully discovered, Cu ZrS , which is achieved by introducing copper ions into both the interlayer and intralayer of ZrS .

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Ge-Sb-Te compounds (GST), the well-known phase-change materials, are considered to be promising thermoelectric (TE) materials due to their decent thermoelectric performance. While GeSbTe and GeSbTe have been extensively studied, the TE performance of GeSbTe has not been well explored. Reducing the excessive carrier concentration is crucial to improving TE performance for GeSbTe.

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Purpose: We aimed to identify effectiveness-associated indicators and evaluate the optimal tumor reduction rate (TRR) after two cycles of neoadjuvant chemotherapy (NAC) in patients with invasive breast cancer.

Methods: This retrospective case-control study included patients who underwent at least four cycles of NAC at the Department of Breast Surgery between February 2013 and February 2020. A regression nomogram model for predicting pathological responses was constructed based on potential indicators.

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Objective: Neoadjuvant therapy (NAT) has been widely implemented as an essential treatment to improve therapeutic efficacy in patients with locally-advanced cancer to reduce tumor burden and prolong survival, particularly for human epidermal growth receptor 2-positive and triple-negative breast cancer. The role of peripheral immune components in predicting therapeutic responses has received limited attention. Herein we determined the relationship between dynamic changes in peripheral immune indices and therapeutic responses during NAT administration.

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Neoadjuvant therapy (NAT) is currently recommended to patients with human epidermal growth factor receptor 2-positive breast cancer (HER2+ BC) that typically exhibit a poor prognosis. The tumor immune microenvironment profoundly affects the efficacy of NAT. However, the correlation between tumor-infiltrating lymphocytes or their specific subpopulations and the response to NAT in HER2+ BC remains largely unknown.

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AgCuSe-based materials have attracted great attentions recently in thermoelectric (TE) field due to their extremely high electron mobility, ultralow lattice thermal conductivity, and abnormal "brittle-ductile" transition at room temperature. However, although the investigation on the crystal structure of AgCuSe low-temperature phase (named as β-AgCuSe) was started more than half a century before, it is still in controversy yet, which greatly limits the understanding of its intriguing electrical, thermal, and mechanical performance. In this work, via adopting the advanced three-dimensional electron diffraction technique, this study finds that the AgCuSe-based materials crystalize in an incommensurately modulated structure with an orthorhombic Pmmn(0β1/2)s00 superspace group.

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