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In angiosperm, two immotile sperm cells are delivered to the female gametes for fertilization by a pollen tube, which perceives guidance cues from ovules at least at two critical sites, micropyle for short distance-guidance and funiculus for comparably longer distance-guidance. Compared with the great progress in understanding pollen tube micropylar guidance, little is known about the signaling for funicular guidance. Here, we show that funiculus plays an important role in pollen tube guidance and report that female gametophyte (FG) plays a critical role in funicular guidance by analysis of a 3-dehydroquinate synthase (DHQS) mutant. Loss function of DHQS in FG interrupts pollen tube funicular guidance, suggesting that the guiding signal is generated from FG. We show the evidence that the capacity of funicular guidance is established during FG functional specification after the establishment of cell identity. Specific expression of DHQS in the synergid cells, central cells or egg cells can rescue funicular guidance defect in dhqs/+, indicating all the female germ unit cells are involved in the funicular guidance. The finding reveals that the attracting signal of pollen tube funicular guidance was generated at a site and stage manner and provides novel clue to locate and search for the signal.

Leber’s hereditary optic neuropathy (LHON) is a maternally inherited eye disease due to mitochondrial DNA (mtDNA) mutations. LHON-linked ND6 14484T > C (p.M64V) mutation affected structural components of complex I but its pathophysiology is poorly understood. The structural analysis of complex I revealed that the M64 forms a nonpolar interaction Y59 in the ND6, Y59 in the ND6 interacts with E34 of ND4L, and L60 of ND6 interacts with the Y114 of ND1. These suggested that the m.14484T > C mutation may perturb the structure and function of complex I. Mutant cybrids constructed by transferring mitochondria from lymphoblastoid cell lines of one Chinese LHON family into mtDNA-less (ρo) cells revealed decreases in the levels of ND6, ND1 and ND4L. The m.14484T > C mutation may affect mitochondrial mRNA homeostasis, supported by reduced levels of SLIRP and SUPV3L1 involved in mRNA degradation and increasing expression of ND6, ND1 and ND4L genes. These alterations yielded decreased activity of complex I, respiratory deficiency, diminished mitochondrial ATP production and reduced membrane potential, and increased production of reactive oxygen species in the mutant cybrids. Furthermore, the m.14484T > C mutation promoted apoptosis, evidenced by elevating Annexin V-positive cells, release of cytochrome c into cytosol, levels in apoptotic proteins BAX, caspases 3, 7, 9 and decreasing levels in anti-apoptotic protein Bcl-xL in the mutant cybrids. Moreover, the cybrids bearing the m.14484T > C mutation exhibited the reduced levels of autophagy protein LC3, increased levels of substrate P62 and impaired PINK1/Parkin-dependent mitophagy. Our findings highlighted the critical role of m.14484T > C mutation in the pathogenesis of LHON.

In order to precisely diagnose the fault type of rotating machinery, a fault diagnosis method for rotating machinery based on improved multiscale attention entropy and random forests is proposed in this study. Firstly, a nonlinear dynamics technique without hyperparameters namely multiscale attention entropy is proposed for measuring signal complexity by extending attention entropy to multiple time scales. Secondly, aiming at the insufficient coarse graining of multiscale attention entropy, composite multiscale attention entropy is exploited to extraction the features of rotating machinery faults. Then, t-distributed stochastic neighbor embedding is used to overcome the feature redundancy problem by reducing the dimension of the extracted features. Finally, the reduced-dimensional features are inputted into the random forests model to complete fault pattern recognition of rotating machinery. The results of the experiment indicate that the proposed method achieves 98.216%and 98.506% diagnosis rates on two different fault datasets respectively, showing an extremely competitive advantage in comparison with conventional diagnosis models. Meanwhile, the proposed method is adopted to the actual hydropower unit without misjudgment, which verifies its strong adaptability. The research proposes a novel method for detecting faults in rotating machinery such as hydropower units.

A direct bandgap type-I Ge QDs/Ge1−y−zSnySiz double-heterostructure on Ge1−xSnx virtual substrates is proposed for SWIR and MWIR lasers. The Ge1−y−zSnySiz barrier is lattice-matched to Ge1−xSnx. The band structures are calculated with different to Sn contents in Ge1−y−zSnySiz and Ge1−xSnx. The band edge energies of Ge QDs vary linearly with x, and independent with y. The Γ-valley is below L-valley when x exceeds 7.5%. The ground states of electrons of Γ- and L-conduction band varies with both x and y. High x and y can increase the conduction band offsets and decrease the valence band offsets. Emission wavelengths range from 1.91 to 4.6 μm are achieved from the proposed structure with proper Sn contents. Emission wavelength of direct bandgap type-I Ge QDs/Ge1-y-zSnySiz on Ge1-xSnx VS.

Pseudouridine (Ψ) at position 55 in tRNAs plays an important role in their structure and function. This modification is catalyzed by TruB/Pus4/Cbf5 family of pseudouridine synthases in bacteria and yeast. However, the mechanism of TRUB family underlying the formation of Ψ55 in the mammalian tRNAs is largely unknown. In this report, the CMC/reverse transcription assays demonstrated the presence of Ψ55 in the human mitochondrial tRNAAsn, tRNAGln, tRNAGlu, tRNAPro, tRNAMet, tRNALeu(UUR) and tRNASer(UCN). TRUB1 knockout (KO) cell lines generated by CRISPR/Cas9 technology exhibited the loss of Ψ55 modification in mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro but did not affect other 18 mitochondrial tRNAs. An in vitro assay revealed that recombinant TRUB1 protein can catalyze the efficient formation of Ψ55 in tRNAAsn and tRNAGln, but not in tRNAMet and tRNAArg. Notably, the overexpression of TRUB1 cDNA reversed the deficient Ψ55 modifications in these tRNAs in TRUB1KO HeLa cells. TRUB1 deficiency affected the base-pairing (18A/G-Ψ55), conformation and stability but not aminoacylation capacity of these tRNAs. Furthermore, TRUB1 deficiency impacted mitochondrial translation and biogenesis of oxidative phosphorylation system. Our findings demonstrated that human TRUB1 is a highly conserved mitochondrial pseudouridine synthase responsible for the Ψ55 modification in the mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro.

A GaSb/GaAsBi type-II quantum dot structure is proposed for fabricating middle-wave infrared (MWIR) and long-wave infrared (LWIR) lasers. The finite element method is employed to investigate the train distributions and band structures of the proposed structures with different Bi contents and QD sizes. It is found that the strain component εxx decreases with Bi contents and heights, and increases with the diameter, while the component εzz inversely changes. The charge carriers recombine between the electrons in GaAsBi QDs and the holes in GaSb. The energy of the ground states of electrons of GaAsBi QDs decreases and the emission wavelength increases with the Bi contents and QD sizes. The emission wavelength can cover MWIR and LWIR ranges with proper Bi contents and QD sizes. The proposed structure provides a feasible way to fabricate MWIR and LWIR lasers.

Neuromelanin (NM) is a dark pigment that mainly exists in neurons of the substantia nigra pars compacta (SNc). In Parkinson disease (PD) patients, NM concentration decreases gradually with degeneration and necrosis of dopamine neurons, suggesting potential use as a PD biomarker. We aimed to evaluate associations between NM concentration in in vivo SN and PD progression and different motor subtypes using NM magnetic resonance imaging (NM-MRI). Fifty-four patients with idiopathic PD were enrolled. Patients were divided into groups by subtypes with different clinical symptoms: tremor dominant (TD) group and postural instability and gait difficulty (PIGD) group. Fifteen healthy age-matched volunteers were enrolled as controls. All subjects underwent clinical assessment and NM-MRI examination. PD patients showed significantly decreased contrast-to-noise ratio (CNR) values in medial and lateral SN (P P = 0.001). PIGD patients showed significant decreases in CNR mean values in lateral SN compared to TD patients (P = 0.004). Diagnostic accuracy of using lateral substantia nigra (SN) in TD and PIGD groups was 79% (sensitivity 76.5%, specificity 78.6%). NM concentration in PD patients decreases gradually during disease progression and differs significantly between PD subtypes. NM may be a reliable biomarker for PD severity and subtype identification.

Background: Post-contrast acute kidney injury (PC-AKI) is a severe complication of cardiac catheterization. Emerging evidence indicated that long non-coding RNAs (lncRNAs) could serve as biomarkers for various diseases. However, the lncRNA expression profile and potential biomarkers in PC-AKI remain unclear. This study aimed to investigate novel lncRNA biomarkers for the early detection of PC-AKI. Methods: lncRNA profile in the kidney tissues of PC-AKI rats was evaluated through RNA sequencing. Potential lncRNA biomarkers were identified through human-rat homology analysis, kidney and blood filtering in rats and verified in 112 clinical samples. The expression patterns of the candidate lncRNAs were detected in HK-2 cells and rat models to evaluate their potential for early detection. Results: In total, 357 lncRNAs were found to be differentially expressed in PC-AKI. We identified lnc-HILPDA and lnc-PRND were conservative and remarkably upregulated in both kidneys and blood from rats and the blood of PC-AKI patients; these lncRNAs can precisely distinguish PC-AKI patients (area under the curve (AUC) values of 0.885 and 0.875, respectively). The combination of these two lncRNAs exhibited improved accuracy for predicting PC-AKI, with 100% sensitivity and 83.93% specificity. Time-course experiments showed that the significant difference was first noted in the blood of PC-AKI rats at 12 h for lnc-HILPDA and 24 h for lnc-PRND. Conclusion: Our study revealed that lnc-HILPDA and lnc-PRND may serve as the novel biomarkers for early detection and profoundly affect the clinical stratification and strategy guidance of PC-AKI.

Bi incorporations can reduce the bandgap of GaAs1-xBix. With a Bi content of 10.5%, GaAsBi is predicted to emit light at 1.55 μm. However, high Bi incorporation is difficult for material growth and deteriorates the optical property of GaAsBi. In this work, a GaAsBi quantum dot (QD)/InAlAs structure on InP platform is proposed to fabricate 1.55 μm laser diodes. Strain distributions and band structures are calculated with different Bi contents and QD sizes using finite element method. High Bi contents and large QD sizes are beneficial for achieving long wavelengths. GaAsBi QD/InAlAs structures with a low Bi content of 5.6% and proper QD sizes, such as a diameter of 30 nm and a height of 6 nm, can emit light at 1.55 μm. The proposed structure can be realized by migration enhanced epitaxy and droplet epitaxy and provides a feasible way for fabricating GaAsBi based 1.55 μm laser diodes applied in fiber-optic communications. The emission wavelength of GaAsBi QDs with different sizes and Bi contents

Highly tensile-strained Ge quantum dots (TS-Ge-QDs) emitting structures with different size were successfully grown on InP substrates by molecular beam epitaxy. Defect-free samples with TS-Ge-QDs were confirmed by transmission electron microscopy. Finite element modeling indicates a maximum tensile strain of 4.5% in the Ge QDs, which is much larger than the required strain to achieve direct bandgap conversion of Ge based on theoretical prediction. Photoluminescence (PL) from a direct bandgap-like transition of TS-Ge-QDs with a peak energy of 0.796 eV was achieved and confirmed by the etch depth-dependent PL, temperature-dependent PL and power-dependent PL. In addition, a strong defect-related peak of 1 eV was observed at room temperature. The band structure of the TS-Ge-QDs emitting structures was calculated to support the experimental results of PL spectra. Achieving PL from direct bandgap-like transitions of TS-Ge-QDs provides encouraging evidence of this promising method for integrated light source on Si photonics platform. National Research Foundation (NRF) Accepted version The authors would like to thank the financial support from the National Research Foundation of Singapore under the Competitive Research Program (NRF–CRP19–2017–01)

Background. Several studies have reported conflicting findings regarding the association between tumor necrosis factor-alpha (TNF-α) genetic polymorphisms and acute kidney injury (AKI). Therefore, we performed this meta-analysis to further investigate whether TNF-α variants are related to AKI susceptibility. Methods. A comprehensive search of observational studies on the association of TNF-α polymorphism with AKI susceptibility was conducted in the PubMed, Cochrane, and Embase databases through February 10, 2020. Pooled odds ratios (ORs) and 95% corresponding confidence intervals (95% CIs) were analyzed to evaluate the strength of the relationship. Results. A total of 8 studies involving 6694 patients (2559 cases and 4135 controls) were included. Pooled analysis showed a trend of increased risk between the TNF-α rs1800629 variant and AKI (A vs. G: OR 95 % CI = 1.33 0.98 ‐ 1.81 ) among the overall population. Ethnicity-stratified analysis indicated that the TNF-α rs1800629 variant was a risk factor for Asians ( OR 95 % CI = 1.93 1.59 ‐ 2.35 ) while it is not for Caucasians ( OR 95 % CI = 1.04 0.91 ‐ 1.20 ). Additionally, we also found that TNF-α rs1799964 polymorphism was observed to have a significant relationship with AKI risk in Asian patients (C vs. T, OR 95 % CI = 1.26 1.11 ‐ 1.43 ). Conclusions. The TNF rs1800629 polymorphism exhibited a trend toward AKI susceptibility with ethnic differences. The relationship was found to be significant among the Asian population, but not among those of Caucasian origin. Additionally, the TNF-α rs1799964 polymorphism was also related to a significantly increased risk of AKI in Asians.

Introduction The brittle response (BR) in patients with Parkinson’s disease (PD) refers to a special type of levodopa‐induced dyskinesia (LID). This study aimed to describe the clinical characteristics of BR patients and to analyze the associated risk factors. Methods A retrospective study was conducted to analyze the data of 97 patients with PD. Patients were divided into a BR group and a non‐brittle response (NBR) group. Demographic and clinical data, motor symptoms, and non‐motor symptoms of the two groups were assessed. Results Among 97 PD patients, 11 were in the BR group and 86 were in the NBR group. The proportion of female patients was 72.7% and 38.3%, respectively, in the BR and NBR groups (P 0.05). Multivariate logistic regression analysis showed that BR patients had lower body weight and higher levodopa dose per weight. Conclusion BR is associated with being female, low body weight, low BMI, long disease duration, high LEDD, and high levodopa dose per weight. Body weight and levodopa dose per body weight are independent risk factors for BR.

Fluorescent biomedical materials can visualize subcellular structures and therapy processes in vivo. The aggregation-induced emission (AIE) phenomenon helps suppress the quenching effect in the aggregated state suffered by conventional fluorescent materials, thereby contributing to design strategies for fluorescent biomedical materials. Photoresponsive biomedical materials have attracted attention because of the inherent advantages of light; i.e., remote control, high spatial and temporal resolution, and environmentally friendly characteristics, and their combination with AIE facilitates development of fluorescent molecules with efficient photochemical reactions upon light irradiation. In this review, organic compounds with AIE features for biomedical applications and design strategies for photoresponsive AIE luminogens (AIEgens) are first summarized briefly. Applications are then reviewed, with the employment of photoresponsive and AIE-active molecules for photoactivation imaging, super-resolution imaging, light-induced drug delivery, photodynamic therapy with photochromic behavior, and bacterial targeting and killing being discussed at length. Finally, the future outlook for AIEgens is considered with the aim of stimulating innovative work for further development of this field.

The use of conventional chemotherapy often faces limitations such as severe side effects, weak tumor tissue specificity, and the development of multidrug resistance. To conquer these challenges, numerous novel drug carriers have been designed in recent years. However, due to the complex processes of tumor development, metastasis and recurrence, single chemotherapy cannot fulfill the goals of clinical diverse treatment. In this work, by utilizing the inherent characteristics of surface-modified erythrocyte and the outstanding photothermal conversion capability of polydopamine (PDA), we designed and constructed a biomimetic multifunctional nanomedicine DPPR NPs to codeliver chemotherapeutic agent doxorubicin (DOX) and oxygen. The results showed that DPPR NPs exhibited inspiring features including nanoscale droplet size, good physicochemical stability, and sustained, pH-, and NIR triggered drug release behavior. It can dramatically prolong the systematic circulation time and elevated the drug accumulated level in the tumor site. Moreover, DPPR NPs could be effectively internalized into tumor cells and destroyed the intracellular redox balance to mediate cell apoptosis. It exerted excellent in vivo tumor targeting effect, photothermal conversion efficiency, ultrasound imaging responses, antitumor efficacy, and good compatibility. In summary, DPPR NPs provide a biomimetic drug delivery platform to organically combine chemotherapy and photothermal therapy for precise cancer treatment.

The performance of the adaptive vector quantization based on k-means clustering for direct-detection terahertz communication in 0.3 THz band is studied by simulation. Compared with the traditional uniform quantization, the two-dimensional k-means quantization can effectively improve the bit error rate by more than an order of magnitude with 2 quantization bits per sample, which can facilitate the low-power and low-cost receivers.

First-principle calculations based on the density functional theory (DFT) are implemented to study the structural and electronic properties of the SiS2/WSe2 hetero-bilayers. It is found that the AB-2 stacking model is most stable among all the six SiS2/WSe2 heterostructures considered in this work. The AB-2 stacking SiS2/WSe2 hetero-bilayer possesses a type-II band alignment with a narrow indirect band gap (0.154 eV and 0.738 eV obtained by GGA-PBE and HSE06, respectively), which can effectively separate the photogenerated electron&ndash, hole pairs and prevent the recombination of the electron&ndash, hole pairs. Our results revealed that the band gap can be tuned effectively within the range of elastic deformation (biaxial strain range from &minus, 7% to 7%) while maintaining the type-II band alignment. Furthermore, due to the effective regulation of interlayer charge transfer, the band gap along with the band offset of the SiS2/WSe2 heterostructure can also be modulated effectively by applying a vertical external electric field. Our results offer interesting alternatives for the engineering of two-dimensional material-based optoelectronic nanodevices.

Background Several studies have reported conflicting findings regarding the association between tumor necrosis factor-alpha (TNF-α) genetic polymorphisms and acute kidney injury (AKI). Therefore, we performed this meta-analysis to further investigate whether TNF-α variants are related to AKI susceptibility. Methods A comprehensive search of observational studies on the association of TNF-α polymorphism with AKI susceptibility was conducted in the PubMed, Cochrane, and Embase databases through February 10, 2020. Pooled odds ratios (ORs) and 95% corresponding confidence intervals (95% CIs) were analyzed to evaluate the strength of the relationship. Results A total of 8 studies involving 6694 patients (2559 cases and 4135 controls) were included. Pooled analysis showed a trend of increased risk between the TNF-α rs1800629 variant and AKI (A vs. G: OR [95%CI] = 1.33 [0.98‐1.81]) among the overall population. Ethnicity-stratified analysis indicated that the TNF-α rs1800629 variant was a risk factor for Asians (OR [95%CI] = 1.93 [1.59‐2.35]) while it is not for Caucasians (OR [95%CI] = 1.04 [0.91‐1.20]). Additionally, we also found that TNF-α rs1799964 polymorphism was observed to have a significant relationship with AKI risk in Asian patients (C vs. T, OR [95%CI] = 1.26 [1.11‐1.43]). Conclusions The TNF rs1800629 polymorphism exhibited a trend toward AKI susceptibility with ethnic differences. The relationship was found to be significant among the Asian population, but not among those of Caucasian origin. Additionally, the TNF-α rs1799964 polymorphism was also related to a significantly increased risk of AKI in Asians.

Topological metals, including Dirac and Weyl semimetals, represent a wide class of quantum materials with non-trivial electronic band structures. The essential properties of Dirac or Weyl fermions, including light effective mass and high mobility, have been observed in a number of semimetal compounds, which in turn exhibit large positive magnetoresistances. Here, we report an unexpected observation of all these properties in α-gallium (α-Ga) single crystals, a pure metal that is in the liquid phase at room temperature and ambient pressure. Based on systematical transport measurements, α-Ga single crystal is found to exhibit large magnetoresistance, reaching about 1.66 × 106 per cent at 2 K in a magnetic field of 9 T. At low temperatures the de Haas–van Alphen and Shubinikov de Hass quantum oscillations show ultrahigh mobility and very small cyclotron effective mass for charge carriers, together with a non-trivial Berry phase. Combined with first-principle band structure calculations, these properties demonstrate α-Ga as a rare topological pure metal. Furthermore, superconductivity with Tc of ~0.9 K is confirmed by both specific heat and resistivity measurements. These findings suggest that α-Ga is a unique pure metal displaying both non-trivial topological and superconducting properties. A comprehensive investigation of bulk properties of α-Ga single crystals grown using a super cooled method—Ga is a metal that is liquid at room temperature—revealed that at very low temperatures this material exhibits a number of interesting properties; in particular, topology and superconductivity coexist. Bin Chen and colleagues measured a very large magnetoresistance, accompanied by a light effective mass and high mobility for the charge carriers, properties that suggest that the material is a topological metal. This conclusion is supported by first-principle calculations. Moreover, previous measurements indicating that the material is superconducting at very low temperature were experimentally confirmed. Materials exhibiting both topological properties and superconductivity provide a useful testing ground for understanding the interplay between superconducting pairing mechanisms and topology of the electronic band structure.

During embryogenesis, plants are thought to use a mechanism that allows the suspensor to maintain its identity. Here, we reported that RPL18aB is involved in this mechanism in Arabidopsis thaliana. The suspensor cells proliferated in rpl18aB and formed a multicellular structure rather than undergo programmed cell death, as in wild type. Suspensors of rpl18aB expressed the embryo proper marker, DRN::GFP, but not the suspensor marker, WOX8::GFP. In addition, auxin accumulated throughout the suspensors of rpl18aB proembryos. Suspensor-specific expression of RPL18aB could rescue the cell proliferation defects in rpl18aB suspensors. These findings supported a role for RPL18aB in maintaining suspensor identity.

A new hydrazine probe was designed, which demonstrates ultrafast “turn-on” response towards hydrazine both in solution and as gas, due to the excellent AIE (aggregation-induced emission) characteristic of the yielded products. Excitedly, the corresponding fabricated test strips can report the presence of trace hydrazine as low as 10 nmol/L in aqueous medium in seconds conveniently, with very high selectivity in the pH value ranging from 3.0 to 14.0.

The nanoscale distribution of Bi in InPBi is determined by atom probe tomography and transmission electron microscopy. The distribution of Bi atoms is not uniform both along the growth direction and within the film plane. A statistically high Bi-content region is observed at the bottom of the InPBi layer close to the InPBi/InP interface. Bi-rich V-shaped walls on the (−111) and (1–11) planes close to the InPBi/InP interface and quasi-periodic Bi-rich nanowalls in the (1–10) plane with a periodicity of about 100 nm are observed. A growth model is proposed to explain the formation of these unique Bi-related nanoscale features. These features can significantly affect the deep levels of the InPBi epilayer. The regions in the InPBi layer with or without these Bi-related nanostructures exhibit different optical properties.

As a promising new class of near-infrared light emitters, GaAsBi laser diodes (LDs) are considered to have a high energy efficiency and an insensitive temperature dependence of the band gap. In this paper, we realize the longest ever reported lasing wavelength up to 1.142 μm at room temperature in GaAsBi0.058/GaAs quantum well LDs grown by molecular beam epitaxy. The output power is up to 127 mW at 300 K under pulsed mode. We also demonstrate continuous wave mode operation up to 273 K for the first time. The temperature coefficient of the GaAsBi/GaAs LD is 0.26 nm/K in the temperature range of 77–350 K, lower than that of both InGaAsP/InP and InGaAs/GaAs LDs. The characteristic temperature is extracted to be 139 K in the temperature range of 77–225 K and decreases to 79 K at 225–350 K.

The specific functions of the genes encoding arginine biosynthesis enzymes in plants are not well characterized. We report the isolation and characterization of Arabidopsis thaliana N-acetylglutamate kinase (NAGK), which catalyzes the second step of arginine biosynthesis. NAGK is a plastid-localized protein and is expressed during most developmental processes in Arabidopsis. Heterologous expression of the Arabidopsis NAGK gene in a NAGK-deficient Escherichia coli strain fully restores bacterial growth on arginine-deficient medium. nagk mutant pollen tubes grow more slowly than wild type pollen tubes and the phenotype is restored by either specifically through complementation by NAGK in pollen, or exogenous supplementation of arginine. nagk female gametophytes are defective in micropylar pollen tube guidance due to the fact that female gametophyte cell fate specification was specifically affected. Expression of NAGK in synergid cells rescues the defect of nagk female gametophytes. Loss-of-function of NAGK results in Arabidopsis embryos not developing beyond the four-celled embryo stage. The embryo-defective phenotype in nagk/NAGK plants cannot be rescued by watering nagk/NAGK plants with arginine or ornithine supplementation. In conclusion, our results reveal a novel role of NAGK and arginine in regulating gametophyte function and embryo development, and provide valuable insights into arginine transport during embryo development.

Introduction The aim of this study was to evaluate whether active intervention can decrease job burnout and improve performance among ED nurses. Methods This study was carried out in the emergency departments of 3 hospitals randomly selected from 8 comprehensive high-level hospitals in Jinan, China. A total of 102 nurses were enrolled and randomly divided into control and intervention groups. For 6 months, nurses in intervention groups were treated with ordinary treatment plus comprehensive management, whereas nurses in the control group were treated with ordinary management, respectively. Questionnaires were sent and collected at baseline and at the end of the study. The Student t test was used to evaluate the effect of comprehensive management in decreasing burnout. Results All ED nurses showed symptoms of job burnout at different levels. Our data indicated that comprehensive management significantly decreased emotional exhaustion and depersonalization ( P Discussion The findings suggest that active intervention with comprehensive management may effectively reduce job burnout in ED nurses and contribute to relieving work-related stress and may further protect against potential mental health problems.

We propose a new type II InGaAs/GaAsBi quantum well structure to extend light emission wavelength on GaAs and demonstrate the effect experimentally. Type II InGaAs/GaAsBi QWs were grown using molecular beam epitaxy. Room temperature photoluminescence confirms wavelength extension to 1230 nm, 82 and 208 nm longer than that of the type I GaAsBi and InGaAs QW with the same Bi or In content, respectively. The PL intensity is enhanced by more than ten times than the GaAsBi QW. Our results show that the type II dilute bismide QW has potentials for making telecom lasers on GaAs.

In order to restore the power service as much as possible, the circuit-breaker of distribution network is reorganized to change distribution network’s operation mode. The topology of distribution network is firstly modeled by path description method. After that, all the possible service restoration paths are searched in the distribution network model by depth priority algorithm. Based on the principle of critical loads to be restored as much as possible, the optimization equations are established to solve the post-disaster reconstruction topology and power service recovery strategy of the distribution network. Moreover, the possible topology of power distribution network and critical load factors are fully considered in the process of service restoration after disaster. The proposed strategy can restore all the critical loads for the massive power outage after a disaster. Advantages are reflected compared with two typical algorithms.

InPBi exhibits broad and strong photoluminescence at room temperature, and is a potential candidate for fabricating super-luminescence diodes applied in optical coherence tomography. In this paper, the strained InPBi quantum dot (QD) embedded in the AlGaAs barrier on a GaAs platform is proposed to enhance the light emission efficiency and further broaden the photoluminescence spectrum. The finite element method is used to calculate the strain distribution, band alignment and confined levels of InPBi QDs. The carrier recombinations between the ground states and the deep levels are systematically investigated. A high Bi content and a flat QD shape are found preferable for fabricating super-luminescence diodes with high efficiency and a broad emission spectrum.

The effects of Bi, In flux and PH3 pressure on Bi incorporation, structural and transport properties of InPBi grown by gas source molecular beam epitaxy have been systematically studied. Incorporation of Bi behaves like a dopant and its content increases linearly with Bi flux and inversely with the InP growth rate (In flux), and is independent of the PH3 pressure studied. High PH3 pressure causes rough surface and introduction of Bi improves surface quality. Intrinsic InP grown at a low temperature reveals n-type due to the P-ln antisite defects and the electron density is proportional to the PH3 pressure and inversely proportional to the InP growth rate. Incorporation of Bi induces p-type dopant that compensates the background electron concentration but doesn't degrade the electron mobility for the Bi content up to 2.4%. These results suggest that there is still a large room left to optimize material quality and maximize Bi incorporation in InPBi using gas source molecular beam epitaxy.