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Conjugated polymers promise inherently flexible and low-cost thermoelectrics for powering the Internet of Things from waste heat1,2. Their valuable applications, however, have been hitherto hindered by the low dimensionless figure of merit (ZT)3-6. Here we report high-ZT thermoelectric plastics, which were achieved by creating a polymeric multi-heterojunction with periodic dual-heterojunction features, where each period is composed of two polymers with a sub-ten-nanometre layered heterojunction structure and an interpenetrating bulk-heterojunction interface. This geometry produces significantly enhanced interfacial phonon-like scattering while maintaining efficient charge transport. We observed a significant suppression of thermal conductivity by over 60 per cent and an enhanced power factor when compared with individual polymers, resulting in a ZT of up to 1.28 at 368 kelvin. This polymeric thermoelectric performance surpasses that of commercial thermoelectric materials and existing flexible thermoelectric candidates. Importantly, we demonstrated the compatibility of the polymeric multi-heterojunction structure with solution coating techniques for satisfying the demand for large-area plastic thermoelectrics, which paves the way for polymeric multi-heterojunctions towards cost-effective wearable thermoelectric technologies.
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The practical application of thermoelectric devices requires both high-performance n-type and p-type materials of the same system to avoid possible mismatches and improve device reliability. Currently, environmentally friendly SnTe thermoelectrics have witnessed extensive efforts to develop promising p-type transport, making it rather urgent to investigate the n-type counterparts with comparable performance. Herein, we develop a stepwise optimization strategy for improving the transport properties of n-type SnTe. First, we improve the n-type dopability of SnTe by PbSe alloying to narrow the band gap and obtain n-type transport in SnTe with halogen doping over the whole temperature range. Then, we introduce additional Pb atoms to compensate for the cationic vacancies in the SnTe-PbSe matrix, further enhancing the electron carrier concentration and electrical performance. Resultantly, the high-ranged thermoelectric performance of n-type SnTe is substantially optimized, achieving a peak ZT of â¼0.75 at 573 K with a high average ZT (ZTave) exceeding 0.5 from 300 to 823 K in the (SnTe0.98I0.02)0.6(Pb1.06Se)0.4 sample. Moreover, based on the performance optimization on n-type SnTe, for the first time, we fabricate an all-SnTe-based seven-pair thermoelectric device. This device can produce a maximum output power of â¼0.2 W and a conversion efficiency of â¼2.7% under a temperature difference of 350 K, demonstrating an important breakthrough for all-SnTe-based thermoelectric devices. Our research further illustrates the effectiveness and application potential of the environmentally friendly SnTe thermoelectrics for mid-temperature power generation.
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Ideal thermoelectrics shall possess a high average ZT, which relies on high carrier mobility and appropriate carrier density at operating temperature. However, conventional doping usually results in a temperature-independent carrier concentration, making performance optimization over a wide temperature range be challenging. This work demonstrates the combination of lattice plainification and dynamic doping strategies is an effective route to boost the average ZT of N-type PbSe. Because Sn and Pb have similar ionic radii and electronegativity, this allows Sn to fill the intrinsic Pb vacancies and effectively improves the carrier mobility of PbSe to 1300 cm2 V-1 s-1. Furthermore, a trace amount of Cu is introduced into the Sn-filled PbSe to optimize the carrier concentration. The extra Cu is situated in the interstitial sides of the lattice, which undergoes a dissolution-precipitation process with temperature, leading to a strongly temperature-dependent carrier density in the material. This dynamic doping effectively improves the electrical transport properties and is also valid to suppress the lattice thermal conductivity. Ultimately, the resulting PbSn0.004Se+3Cu obtains a maximum ZT of ≈1.7 at 800 K and an average ZT of ≈1.0, with a 7.7% power generation efficiency in a single-arm device, showing significant potential for commercial application.
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The scarcity of Te hampers the widespread use of Bi2Te3-based thermoelectric modules. Here, the thermoelectric module potential of PbSe is investigated by improving its carrier mobility. Initially, large PbSe crystals are grown with the temperature gradient method to mitigate grain boundary effects on carrier transport. Subsequently, light doping with <1mole halogens (Cl/Br/I) increases room-temperature carrier mobility to ~1600 cm2 V-1 s-1, achieved by reducing carrier concentration compared to traditional heavy doping. Crystal growth design and light doping enhance carrier mobility without affecting effective mass, resulting in a high power factor ~40 µW cm-1 K-2 in PbSe-Cl/Br/I crystals at 300 K. Additionally, Cl/Br/I doping reduces thermal conductivity and bipolar diffusion, leading to significantly lower thermal conductivity at high temperature. Enhanced carrier mobility and suppressed bipolar effect boost ZT values across the entire temperature range in n-type PbSe-Cl/Br/I crystals. Specifically, ZT values of PbSe-Br crystal reach ~0.6 at 300 K, ~1.2 at 773 K, and the average ZT (ZTave) reaches ~1.0 at 300-773 K. Ultimately, ~5.8% power generation efficiency in a PbSe single leg with a maximum temperature cooling difference of 40 K with 7-pair modules is achieved. These results indicate the potential for cost-effective and high-performance thermoelectric cooling modules based on PbSe.
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ConspectusThe growing energy crisis and the adverse environmental impacts caused by carbon-based energy consumption have spurred the exploration of green and sustainable energy. Researchers have been devoted to developing thermoelectric technology that could directly and reversibly convert heat into electricity. By virtue of zero emissions, nonmoving parts, precise temperature control, and long service life, thermoelectrics exhibit broad application in power generation and refrigeration. Nevertheless, traditional narrow-bandgap thermoelectrics exhibit high performance within a narrow temperature range, limiting the overall energy conversion. Consequently, a selection rule for exploring advanced thermoelectrics was proposed: materials with wide-bandgap, crystals form, asymmetry, and anisotropic structure. According to the rules, we conducted much research and found some promising materials.As the lead-free, cost-effective, and stable thermoelectric candidates, layered SnSe crystals with wide-bandgap and covalent bonding have gained significant attention due to their ultralow thermal conductivity resulting from strong bonding anharmonicity, via strong polar covalent bonding, because of the electronegativity difference between the Sn and Se atoms. This was proved to be the result from the unique structure of layered SnSe crystals, a distorted rock-salt structure with high and anisotropic Grüneisen parameters. In this Account, we introduce and rethink our recent advancements in developing high-performance thermoelectric SnSe crystals from computational materials science, involving p- and n-type SnSe crystals, respectively. For p-type SnSe crystals, according to the complex valence band structures, we utilized the multiband synglisis via electronic structure calculations and multiband simulations to activate valence bands to participate in electrical transport of in-plane direction, achieving an ultrahigh power factor (PF) of â¼75 µW cm-1 K-2 at room temperature and an average figure-of-merit ZTave of â¼1.9 for Sn0.91Pb0.09Se. Besides, on the basis of defect chemistry, the characteristics of p-type SnSe crystals are determined by intrinsic Sn vacancies. We thus used point-defect calculations to achieve the lattice plainification, and we fixed the lattice intrinsic defects to weaken defect scattering of carriers along the in-plane direction, facilitating further a PF > 100 µW cm-1 K-2 and a ZT of â¼1.5 at room temperature for SnCu0.001Se. For n-type SnSe crystals, inspired by the anisotropic characteristics of the layered materials, we analyzed charge density and proposed the insight of 3D charge and 2D phonon transports and calculated the deformation potential to manipulate layered phonon-electron decoupling to achieve high performance, ultimately Pb-alloyed and Cl-doped SnSe (SnSe-Cl-PbSe) reaching a ZTave of â¼1.7 from 300 to 773 K. In the end, we offer potential perspectives on high-throughput calculations (HTC) and machine learning (ML), combined with our proposed insights, which could be a promising avenue for future thermoelectrics. By virtue of our theoretical and experimental understanding of thermoelectrics, integrating these insights as rules and descriptors for HTC and ML will accelerate the research and development of thermoelectrics. We want to share our recent works and latest perspectives in SnSe thermoelectrics, and we expect to inspire enthusiasm for innovative research on advanced thermoelectric materials and devices.
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Multiple myeloma (MM) is a common hematological malignancy, and patients with MM are recommended to take immunomodulatory drugs such as lenalidomide along with proteasome inhibitors such as bortezomib to extend survival. However, drug resistance influences the efficacy of treatment for MM. In our study, we found that metformin and chidamide both suppressed MM cell growth in a concentration- and time-dependent way (p < .001). Moreover, combined therapy with metformin and chidamide exhibited enhanced inhibition of the growth of MM cells compared with monotherapy (p < .05). Additionally, the triple-drug combination of metformin and chidamide with lenalidomide or bortezomib was used to stimulate the MM cells, and the results revealed that metformin and chidamide treatment sensitized MM cells to lenalidomide and bortezomib. As a result, the apoptosis (p < .001) together with cell cycle arrest at G0/G1 phase (p < .05) was stimulated by lenalidomide and bortezomib, and showed significant elevation in the triple-drug combination group compared with the lenalidomide or bortezomib treatment alone group (p < .05). Furthermore, the impacts of different drugs on glycolysis in MM cells were examined. We found that metformin and chidamide combined treatment significantly promoted glucose uptake and reduced energy production in MM cells treated with lenalidomide and bortezomib (p < .001), suggesting that metformin and chidamide affected glycolysis in MM cells and enhanced the sensitivity of lenalidomide and bortezomib in MM by regulating glucose metabolism. In conclusion, metformin and chidamide synergistically hindered MM cell growth and sensitized cells to lenalidomide/bortezomib. The findings of this study might provide novel clues to improve MM therapy.
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Aminopiridinas , Benzamidas , Metformina , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , Metformina/farmacologia , Dexametasona/uso terapêutico , Combinação de MedicamentosRESUMO
The room-temperature thermoelectric performance of materials underpins their thermoelectric cooling ability. Carrier mobility plays a significant role in the electronic transport property of materials, especially near room temperature, which can be optimized by proper composition control and growing crystals. Here, we grow Pb-compensated AgPb18+xSbTe20 crystals using a vertical Bridgman method. A large weighted mobility of â¼410 cm2 V-1 s-1 is achieved in the AgPb18.4SbTe20 crystal, which is almost 4 times higher than that of the polycrystalline counterpart due to the elimination of grain boundaries and Ag-rich dislocations verified by atom probe tomography, highlighting the significant benefit of growing crystals for low-temperature thermoelectrics. Due to the largely promoted weighted mobility, we achieve a high power factor of â¼37.8 µW cm-1 K-2 and a large figure of merit ZT of â¼0.6 in AgPb18.4SbTe20 crystal at 303 K. We further designed a 7-pair thermoelectric module using this n-type crystal and a commercial p-type (Bi, Sb)2Te3-based material. As a result, a high cooling temperature difference (ΔT) of â¼42.7 K and a power generation efficiency of â¼3.7% are achieved, revealing promising thermoelectric applications for PbTe-based materials near room temperature.
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OBJECTIVE: To investigate the carrier rate and clinical characteristics of epigenetic modification gene mutations (EMMs) among patients with acute myeloid leukemia (AML). METHODS: One hundred seventy two patients who were initially diagnosed with AML at the First People's Hospital of Lianyungang from May 2011 to February 2021 were selected as the study subjects. Next-generation sequencing was carried out to detect variants of 42 myeloid genes among these patients. Clinical and molecular characteristics of patients with EMMs and the effect of demethylation drugs (HMAs) on their survival were analyzed. RESULTS: Among the 172 AML patients, 71 (41.28%) were found to harbor the EMMs, and carrier rates were TET2 (14.53%, 25/172), DNMT3A (11.63%, 20/172), ASXL1 (9.30%, 16/172), IDH2 (9.30%, 16/172), IDH1 (8.14%, 14/172), EZH2 (0.58%, 1/172). Patients with EMMs (+) had lower peripheral hemoglobin compared with those with EMMs(-) (72 g/L vs. 88 g/L, Z = -1.985, P = 0.041). The proportion of EMMs(+) among elderly AML patients was significantly higher than that of young AML patients[71.11% (32/45) vs. 30.70% (39/127), χ² = 22.38, P < 0.001]. EMMs(+) were significantly correlated with NPM1 gene variants (r = 0.413, P < 0.001), while negatively correlated with CEPBA double variants (r = -0.219, P < 0.05). Compared with conventional chemotherapy regimens, HMAs-containing chemotherapy regimens have improved the median progression-free survival (PFS) and median overall survival (OS) among intermediate-risk AML patients with EMMs(+) (PFS: 11.5 months vs. 25.5 months, P < 0.05; 12.5 months vs. 27 months, P < 0.05). Similarly, Compared with conventional chemotherapy regimens, chemotherapy with HMAs had increased median PFS and median OS in elderly AML patients with EMMs(+) (4 months vs. 18.5 months, P < 0.05; 7 months vs. 23.5 months, P < 0.05). CONCLUSION: Patients with AML have a high rate of EMMs carriage, and HMAs-containing chemotherapy regimens can prolong the survival of elderly patients with AML with poor prognosis, which may provide a reference for individualized treatment.
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Leucemia Mieloide Aguda , Nucleofosmina , Humanos , Idoso , Prognóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Epigênese GenéticaRESUMO
Many Zintl phases are promising thermoelectric materials owning to their features like narrow band gaps, multiband behaviors, ideal charge transport tunnels, and loosely bound cations. Herein we show a new Zintl phase NaCdSb with exceptional intrinsic thermoelectric performance. Pristine NaCdSb exhibits semiconductor behaviors with an experimental hole concentration of 2.9×1018 â cm-3 and a calculated band gap of 0.5â eV. As the temperature increases, the hole concentration rises gradually and approaches its optimal one, leading to a high power factor of 11.56â µW cm-1 K-2 at 673â K. The ultralow thermal conductivity is derived from the small phonon group velocity and short phonon lifetime, ascribed to the structural anharmonicity of Cd-Sb bonds. As a consequence, a maximum zT of 1.3 at 673â K has been achieved without any doping optimization or structural modification, demonstrating that NaCdSb is a remarkable thermoelectric compound with great potential for performance improvement.
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Piezoelectric nanomaterials open new avenues in driving green catalysis processes (e.g., H2 evolution from water) through harvesting mechanical energy, but their catalytic efficiency is still limited. The predicted enormous piezoelectricity for 2D SnSe, together with its high charge mobility and excellent flexibility, renders it an ideal candidate for stimulating piezocatalysis redox reactions. In this work, few-layer piezoelectric SnSe nanosheets (NSs) are utilized for mechanically induced H2 evolution from water. The finite elemental method simulation demonstrates an unprecedent maximal piezoelectric potential of 44.1 V for a single SnSe NS under a pressure of 100 MPa. A record-breaking piezocurrent density of 0.3 mA cm-2 is obtained for SnSe NSs-based electrode under ultrasonic excitation (100 W, 45 kHz), which is about three orders of magnitude greater than that of reported piezocatalysts. Moreover, an exceptional H2 production rate of 948.4⯵molâ¯g-1 h-1 is achieved over the SnSe NSs without any cocatalyst, far exceeding most of the reported piezocatalysts and competitive with the current photocatalysis technology. The findings not only enrich the potential piezocatalysis materials, but also provide useful guidance toward high-efficiency mechanically driven chemical reactions such as H2 evolution from water.
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Due to the intrinsically plentiful Sn vacancies, developing n-type SnTe thermoelectric materials is a big challenge. Herein, n-type SnTe thermoelectric materials with remarkable performance were successfully synthesized through suppressing Sn vacancies, followed by electron-doping. Pb alloying notably depressed the Sn vacancies via populating Sn vacancies in SnTe (supported by transmission electron microscopy), and the electrical transports were shifted from p-type to n-type through introducing electrons using I doping. In the n-type SnTe, we found that the electrical conductivity could be enhanced by increased carrier mobility through sharpening conduction bands after alloying Pb, while the lattice thermal conductivity could be reduced via strong phonon scattering after introducing defects by Pb alloying and I doping. Resulting from these enhancements, the n-type Sn0.6Pb0.4Te0.98I0.02 achieves a notably high ZTmax â¼ 0.8 at 573 K and a remarkable ZTave â¼ 0.51 at 300-823 K, which can match many excellent p-type SnTe. This work indicates that n-type SnTe could be experimentally acquired and is a promising candidate for thermoelectric generation, which will stimulate further research on n-type SnTe thermoelectric materials and even devices on the basis of both n- and p-type SnTe legs.
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AIM: Trophoblastic and vascular endothelial injuries were closely associated with the pathogenesis of hypertensive disorder complicating pregnancy (HDCP). The present study was designed to determine the functional role of baicalin in the proliferation and invasion of trophoblasts and vascular endothelial injury. METHODS: Ang II was adopted to stimulate HTR-8/SVneo and human umbilical vein endothelial cells (HUVECs). Cell viability was examined by CCK-8 assay. Flow cytometry and TUNEL staining determined cell apoptosis. Invasive ability of HTR-8/SVneo cells was measured by transwell assay. In vitro angiogenesis of HUVECs was assessed by Tube formation assay. In addition, the production of reactive oxygen species (ROS) was determined by DCFH-DA staining. Furthermore, long non-coding RNA (lncRNA) NEAT1 and miRNA-205-5p levels were detected using real-time quantitative polymerase chain reaction and the binding relationship between lncRNA NEAT1 and miRNA-205-5p was verified by dual-luciferase reporter assay. Moreover, interactions among lncRNA NEAT1, miRNA-205-5p, and MMP9 or vascular endothelial growth factor (VEGF) were confirmed by RNA immunoprecipitation assay. RESULTS: Baicalin visibly improved cell viability, reduced the apoptosis of Ang II-stimulated HTR-8/SVneo and HUVEC cells, and repressed overproduction of ROS. Additionally, baicalin promoted the invasion of Ang II-stimulated HTR-8/SVneo cells and induced a stronger in vitro angiogenesis of Ang II-stimulated HUVECs. What's more, baicalin upregulated lncRNA NEAT1 expression and downregulated miR-205-5p expression. LncRNA NEAT1 sponged miR-205-5p and inhibited the combination of miR-205-5p and MMP9 or VEGF. CONCLUSIONS: Baicalin can facilitate the proliferation and invasion of trophoblasts and alleviate vascular endothelial damage by upregulating lncRNA NEAT1 to impede the interaction between miR-205-5p and MMP9 or VEGF.
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Flavonoides/farmacologia , Hipertensão Induzida pela Gravidez/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Trofoblastos/efeitos dos fármacos , Proliferação de Células , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , MicroRNAs/genética , Gravidez , Fator A de Crescimento do Endotélio VascularRESUMO
Crystalline SnSe has been revealed as an efficient thermoelectric candidate with outstanding performance. Herein, record-high thermoelectric performance is achieved among SnSe crystals via simply introducing a small amount of SnSe2 as a kind of extrinsic defect dopant. This excellent performance mainly arises from the largely enhanced power factor by increasing the carrier concentration high as 6.55 × 1019 cm-3, which was surprisingly promoted by introducing extrinsic SnSe2 even though pristine SnSe2 is an n-type conductor. The optimized carrier concentration promotes a deeper Fermi level and activates more valence bands, leading to an extraordinary room-temperature power factor â¼54 µW cm-1 K-2 through enlarging the band effective mass and Seebeck coefficient. As a result, on the basis of simultaneously depressed thermal conductivity induced from both Sn vacancies and SnSe2 microdomains, maximum ZT values â¼0.9-2.2 and excellent average ZT > 1.7 among the working temperature range are achieved in Na doped SnSe crystals with 2% extrinsic SnSe2. Our investigation illustrates new approaches on improving thermoelectric performance through introducing defect dopants, which might be well-implemented in other thermoelectric systems.
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Low-cost and earth-abundant PbS-based thermoelectrics are expected to be an alternative for PbTe, and have attracted extensive attentions from thermoelectric community. Herein, a maximum ZT (ZTmax) ≈ 1.3 at 923 K in n-type PbS is obtained through synergistically optimizing quality factor with Sn alloying and PbTe phase incorporation. It is found that Sn alloying in PbS can sharpen the conduction band shape to balance the contradictory interrelationship between carrier mobility and effective mass, accordingly, a peak power factor of â¼19.8 µWcm-1K-2 is achieved. Besides band sharpening, Sn alloying can also narrow the band gap of PbS so as to make the conduction band position between Pb0.94Sn0.06S and PbTe well aligned, which can benefit high carrier mobility. Therefore, incorporating the PbTe phase into the Pb0.94Sn0.06S matrix can not only favorably maintain the carrier mobility at â¼150 cm2V-1s-1 but also suppress the lattice thermal conductivity to â¼0.61 Wm-1K-1 in Pb0.94Sn0.06S-8%PbTe, which contributes to a largely enhanced quality factor. Consequently, an average ZT (ZTave) ≈ 0.72 in 300-923 K is achieved in Pb0.94Sn0.06S-8%PbTe that outperforms other n-type PbS-based thermoelectric materials.
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The thermoelectric effect enables direct and reversible conversion between thermal and electrical energy, and provides a viable route for power generation from waste heat. The efficiency of thermoelectric materials is dictated by the dimensionless figure of merit, ZT (where Z is the figure of merit and T is absolute temperature), which governs the Carnot efficiency for heat conversion. Enhancements above the generally high threshold value of 2.5 have important implications for commercial deployment, especially for compounds free of Pb and Te. Here we report an unprecedented ZT of 2.6 ± 0.3 at 923 K, realized in SnSe single crystals measured along the b axis of the room-temperature orthorhombic unit cell. This material also shows a high ZT of 2.3 ± 0.3 along the c axis but a significantly reduced ZT of 0.8 ± 0.2 along the a axis. We attribute the remarkably high ZT along the b axis to the intrinsically ultralow lattice thermal conductivity in SnSe. The layered structure of SnSe derives from a distorted rock-salt structure, and features anomalously high Grüneisen parameters, which reflect the anharmonic and anisotropic bonding. We attribute the exceptionally low lattice thermal conductivity (0.23 ± 0.03 W m(-1) K(-1) at 973 K) in SnSe to the anharmonicity. These findings highlight alternative strategies to nanostructuring for achieving high thermoelectric performance.
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The simple binary compound SnSe has been reported as a robust thermoelectric material for energy conversion by showing strong anharmonicity and multiple electronic valence bands. Herein, we report a record-high average ZT value of â¼1.6 at 300-793 K with maximum ZT values ranging from 0.8 at 300 K to 2.1 at 793 K in p-type SnSe crystals. This remarkable thermoelectric performance arises from the enhanced power factor and lowered lattice thermal conductivity through crystal structure modification via Te alloying. Our results elucidate that Te alloying increases the carrier mobility by making the bond lengths more nearly equal and sharpening the valence bands; meanwhile, the Seebeck coefficient remains large due to multiple valence bands. As a result, a record-high power factor of â¼55 µW cm-1 K-2 at 300 K is achieved. Additionally, Te alloying promotes Sn atom displacements, thus leading to a lower lattice thermal conductivity. Our conclusions are well supported by electron localization function calculations, the Callaway model, and structural characterization via aberration-corrected scanning transmission electron microscopy. Our approach of modifying crystal structures could also be applied in other low-symmetry thermoelectric materials and represents a new strategy to enhance thermoelectric performance.
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PURPOSE: The benefits of concurrent newborn hearing and genetic screening have not been statistically proven due to limited sample sizes and outcome data. To fill this gap, we analyzed outcomes of newborns with genetic screening results. METHODS: Newborns in China were screened for 20 hearing-loss-related genetic variants from 2012 to 2017. Genetic results were categorized as positive, at-risk, inconclusive, or negative. Hearing screening results, risk factors, and up-to-date hearing status were followed up via phone interviews. RESULTS: Following up 12,778 of 1.2 million genetically screened newborns revealed a higher rate of hearing loss by three months of age among referrals from the initial hearing screening (60% vs. 5.0%, P < 0.001) and a lower rate of lost-to-follow-up/documentation (5% vs. 22%, P < 0.001) in the positive group than in the inconclusive group. Importantly, genetic screening detected 13% more hearing-impaired infants than hearing screening alone and identified 2,638 (0.23% of total) newborns predisposed to preventable ototoxicity undetectable by hearing screening. CONCLUSION: Incorporating genetic screening improves the effectiveness of newborn hearing screening programs by elucidating etiologies, discerning high-risk subgroups for vigilant management, identifying additional children who may benefit from early intervention, and informing at-risk newborns and their maternal relatives of increased susceptibility to ototoxicity.
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Testes Genéticos/métodos , Perda Auditiva/genética , Triagem Neonatal/métodos , China/epidemiologia , Surdez/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/tendências , Genética Populacional , Perda Auditiva Neurossensorial/diagnóstico , Testes Auditivos , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal/tendênciasRESUMO
BACKGROUND: MYO15A variants are responsible for human non-syndromic autosomal recessive deafness (DFNB3). The majority of MYO15A variants are associated with a congenital severe-to-profound hearing loss phenotype, except for MYO15A variants in exon 2, which cause a milder auditory phenotype, suggesting a genotype-phenotype correlation of MYO15A. However, MYO15A variants not in exon 2 related to a milder phenotype have also been reported, indicating that the genotype-phenotype correlation of MYO15A is complicated. This study aimed to provide more cases of MYO15A variation with diverse phenotypes to analyse this complex correlation. METHODS: Fifteen Chinese autosomal recessive non-syndromic hearing loss (ARNSHL) individuals with MYO15A variants (8 males and 7 females) from 14 unrelated families, identified by targeted gene capture of 127 known candidate deafness genes, were recruited. Additionally, we conducted a review of the literature to further analyses all reported MYO15A genotype-phenotype relationships worldwide. RESULTS: We identified 16 novel variants and 12 reported pathogenic MYO15A variants in 15 patients, two of which presented with a milder phenotype. Interestingly, one of these cases carried two reported pathogenic variants in exon 2, while the other carried two novel variants not in exon 2. Based on our literature review, MYO15A genotype-phenotype correlation analysis showed that almost all domains were reported to be correlated with a milder phenotype. However, variants in the N-terminal domain were more likely to cause a milder phenotype. Using next-generation sequencing (NGS), we also found that the number of known MYO15A variants with milder phenotypes in Southeast Asia has increased in recent years. CONCLUSION: Our work extended the MYO15A variant spectrum, enriched our knowledge of auditory phenotypes, and tried to explore the genotype-phenotype correlation in different populations in order to investigate the cause of the complex MYO15A genotype-phenotype correlation.
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Genes Recessivos , Genótipo , Perda Auditiva/genética , Miosinas/genética , Fenótipo , Adolescente , Adulto , Pré-Escolar , China , Etnicidade , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Oblique incidence is the normal working mode for diffractive optical elements (DOEs). The diffraction efficiency is very sensitive to the angle of incidence for multilayer diffractive optical elements (MLDOEs). Therefore, the design and diffraction efficiency analysis of MLDOEs with wide angles of incidence is of universal significance and practice. We propose an integral diffraction efficiency model for MLDOEs with wide angles of incidence in case of polychromatic light and then describe this corresponding optimal design in detail. It is shown that high diffraction efficiency can be realized by the surface micro-structure heights optimization, ensuring high modulation transfer function (MTF) for MLDOEs with wide angles of incidence in hybrid optical systems. On this basis, we present the optimal design process and simulation of an MLDOE working in visible waveband with optical plastic materials combination PMMA and POLYCARB as the two-layer substrates. The result shows that with this optimal design, we can achieve the maximum diffraction efficiency and minimum micro-structure heights, which makes the MLDOE design exactly over the entire waveband and wide angles of incidence especially for zoom hybrid optical system.
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Although the binary sulfides Bi2S3, PbS, and SnS have attracted extensive interest as thermoelectric materials, no quaternary sulfides containing Sn/Pb/Bi/S elements have been reported. Herein, we report the synthesis of a new quaternary sulfide, SnPb2Bi2S6, which crystallizes in the orthorhombic space group Pnma with unit cell parameters of a = 20.5458(12) Å, b = 4.0925(4) Å, c = 13.3219(10) Å. SnPb2Bi2S6 has a lillianite-type crystal structure consisting of two alternately aligned NaCl-type structural motifs separated by a mirror plane of PbS7 monocapped trigonal prisms. In the lillianite homologous series, SnPb2Bi2S6 can be classified as 4,4L, where the superscripted numbers indicate the maximum numbers of edge-sharing octahedra in the two adjacent NaCl-shaped slabs along the diagonal direction. The obtained SnPb2Bi2S6 phase exhibited good thermal stability up to 1000 K and n-type degenerate semiconducting behavior, with a power factor of 3.7 µW cm-1 K-2 at 773 K. Notably, this compound exhibited a very low lattice thermal conductivity of 0.69-0.92 W m-1 K-1 at 300-1000 K. Theoretical calculations revealed that the low thermal conductivity is caused by the complex crystal structure and the related elastic properties of a low Debye temperature, low phonon velocity, and large Grüneisen parameters. A reasonable figure of merit (ZT) of â¼0.3 was obtained at 770 K.