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Objective: To investigate whether there is an impact of the Chinese New Year (CNY) holiday season on the outcomes of In Vitro Fertilization (IVF) fresh embryo transfer cycles. Study Design: A retrospective study Subjects: 4,688 patients receiving their first IVF fresh cycle attempt between January 2017 and October 2021 were included in the study, of which 4,449 women underwent IVF during non-holiday seasons, while 239 women were treated during the CNY holiday season. Main Outcome Measure(s): The primary outcome was the live birth rate (LBR). Result(s): The liver birth rate (LBR) of IVF performed during the CNY holiday season was 32.22%, significantly lower than that of the non-holiday season (43.38%, pConclusion: This research demonstrated for the first time the existence of a decline in the LBR of IVF performed during the CNY holiday season. IVF performed during the Chinese New Year holiday season results in a declined live birth rate. The abrupt lifestyle change, emotional stress, and traveling may have contributed to such an effect.

BACKGROUND: Chinese New Year is the biggest festival in Chinese culture and the holiday season includes January and February. People have to change their life patterns to celebrate this traditional holiday, so embryo transfer during this holiday season may be affected. METHODS: This is a retrospective cohort to analyze IVF outcomes by month. The primary outcome is the live birth rate. Data were analyzed by multivariate logistic regression. Propensity score matching (PSM) data and inverse probability of treatment weighting (IPTW) data were analyzed as sensitivity analysis. RESULTS: Totally 4,688 patients were recruited. Of 4,449 women in the non-holiday season group, 1,930 had live birth (43.38%), while 77 of 239 women in the holiday season group had live birth (32.22%), p

Background: A valid, reliable, accessible, engaging, and affordable digital cognitive screen instrument for clinical use is in urgent demand. Objective: To assess the clinical utility of the MemTrax memory test for early detection of cognitive impairment in a Chinese cohort. Methods: The 2.5-minute MemTrax and the Montreal Cognitive Assessment (MoCA) were performed by 50 clinically diagnosed cognitively normal (CON), 50 mild cognitive impairment due to AD (MCI-AD), and 50 Alzheimer’s disease (AD) volunteer participants. The percentage of correct responses (MTx-% C), the mean response time (MTx-RT), and the composite scores (MTx-Cp) of MemTrax and the MoCA scores were comparatively analyzed and receiver operating characteristic (ROC) curves generated. Results: Multivariate linear regression analyses indicated MTx-% C, MTx-Cp, and the MoCA score were significantly lower in MCI-AD versus CON and in AD versus MCI-AD groups (all with p≤0.001). For the differentiation of MCI-AD from CON, an optimized MTx-% C cutoff of 81% had 72% sensitivity and 84% specificity with an area under the curve (AUC) of 0.839, whereas the MoCA score of 23 had 54% sensitivity and 86% specificity with an AUC of 0.740. For the differentiation of AD from MCI-AD, MTx-Cp of 43.0 had 70% sensitivity and 82% specificity with an AUC of 0.799, whereas the MoCA score of 20 had 84% sensitivity and 62% specificity with an AUC of 0.767. Conclusion: MemTrax can effectively detect both clinically diagnosed MCI and AD with better accuracy as compared to the MoCA based on AUCs in a Chinese cohort.

Research question：When polycystic ovary syndrome (PCOS) patients undergo in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) and embryo transfer (ET), popular protocols include gonadotropin-releasing hormone agonist (GnRH-a) long protocol, GnRH antagonist protocol, and depot GnRH agonist protocol. There is no consensus regarding which protocol is the most optimal for PCOS patients, so we sought to evaluate depot GnRH agonist protocol versus GnRH antagonist protocol in terms of IVF outcome for PCOS patients in a single fertility center.Design：In this retrospective cohort, we included 533 PCOS patients who were undergoing their first IVF cycle. Among them, 470 were in the depot agonist group and 63 in the antagonist group. Fresh live birth rate (LBR) was the primary outcome. The secondary outcome was cumulative live birth rate (CLBR).Results：Women in the depot GnRH agonist group had a higher LBR (49.79%) than those in the antagonist group (34.92%), p=0.027. Multi-variable logistic regression showed that women in the depot GnRH agonist group had a higher LBR than those in the antagonist group (OR=1.83, p=0.032, 95% CI 1.05~3.18). After propensity score matching (PSM), the LBR in the depot GnRH agonist group was higher (50.32%) than that of the antagonist group (35.48%), p=0.033. Multi-variable logistic regression showed that women in the depot GnRH agonist group had a higher CLBR than those in the antagonist group (OR=1.77, p=0.038, 95% CI 1.03, 3.04). After PSM, CLBR in the depot GnRH agonist group was higher (60.00%) than that of the antagonist group (46.77%), p=0.054. Six patients (9.52%) in the antagonist group and 35 patients (7.45%) in the depot GnRH agonist group had ovarian hyper-stimulation syndrome (OHSS).Conclusions：In our experience, depot GnRH agonist can provide higher LBR and CLBR than the antagonist protocol can. Meanwhile, OHSS can be controlled at a satisfactory level for safe participation in both protocols.

Hypertensive retinopathy refers to the retinal vascular changes associated with systemic arterial hypertension. Hypertensive retinopathy can be divided into chronic and acute phases. A cross‐sectional study was performed to explore a method of measurement in the diameters of retinal vessels for diagnosis of chronic hypertensive retinopathy based on spectral domain optical coherence tomography (SD‐OCT). The central retinal artery diameter (CRAD), the central retinal vein diameter (CRVD), and the artery‐to‐vein ratio (AVR) were measured. A total of 119 subjects with 119 eyes were included in this study, in which 56 subjects with 56 eyes were included in hypertensive group and 63 subjects with 63 eyes were included in normotensive group. There were significant differences between the two groups in the CRAD (t = −2.14, P = .04) and the AVR (t = −2.59, P = .01). The cutoff point of 0.75 was determined by receiver operating characteristic (ROC) curve (area under the curve, AUC 0.786; 95% confidence interval, 95% CI 0.70‐0.87). Multivariate logistic regression analysis showed the probability of AVR below to 0.75 was more in patients with high systolic blood pressure (odds ratio OR 4.39; P = .048), more in male (OR 4.15; P = .004) and more in smokers (OR 5.80; P = .01). Bland‐Altman plots showed small mean bias between the measurements of the two technicians in the CRAD, the CRVD, and the AVR. In summary, application of SD‐OCT is an accurate, reproducible, convenient method for measuring the diameters of retinal vessels. It is valuable for the diagnosis of chronic stage of hypertensive retinopathy.

Purpose: To evaluate the treatment solutions and effectiveness of intravitreal ranibizumab (RBZ) or conbercept in patients with wet age-related macular degeneration (wAMD) in a real-life setting in China.Methods: The medical records of 368 patients with wAMD who started RBZ or conbercept treatment between 1 May 2014 and 30 April 2018 were evaluated. All patients were defined on fundus angiography at baseline to determine the subtype of AMD (PCV or CNV). We report visual acuity (VA) and central retinal thickness (CRT) measurements at baseline and 12 months.Results: The average number of anti-VEGF injections was 2.1 ± 1.2. The BCVA improvement of these two groups was similar with a difference of 1.00 letter (95% CI: −1.4~3.4, p = 0.8505). At the end of the study, a BCVA increase of at least 5 letters was determined to be a satisfactory efficacy endpoint. Several factors were related to the possible improvement in the satisfactory efficacy endpoint, including female sex (OR 2.07, 95% CI 1.22~3.51), number of injections (OR 1.40, 95% CI 1.12~1.75) and VA change at the first month (OR 13.75, 95% CI 7.41~25.51). Additionally, some factors were related to the possible reduction in the satisfactory efficacy endpoint, including diabetes (OR 0.27, 95% CI 0.10~0.73) and disease history (OR 0.75, 95% CI 0.57~0.98).Conclusion: Our study demonstrates that anti-VEGF drugs can effectively improve BCVA and reduce CRT in AMD patients. Sex, number of injections, VA change at the first month, diabetes and disease history are the most important factors affecting visual acuity.

Endocytosis is essential to all eukaryotes, but how cargoes are selected for internalization remains poorly characterized. Extracellular cargoes are thought to be selected by transmembrane receptors that bind intracellular adaptors proteins to initiate endocytosis. Here, we report a mechanism for clathrin-mediated endocytosis (CME) of extracellular lanthanum [La(III)] cargoes, which requires extracellular arabinogalactan proteins (AGPs) that are anchored on the outer face of the plasma membrane. AGPs were colocalized with La(III) on the cell surface and in La(III)-induced endocytic vesicles in Arabidopsis leaf cells. Superresolution imaging showed that La(III) triggered AGP movement across the plasma membrane. AGPs were then colocalized and physically associated with the μ subunit of the intracellular adaptor protein 2 (AP2) complexes. The AGP-AP2 interaction was independent of CME, whereas AGP’s internalization required CME and AP2. Moreover, we show that AGP-dependent endocytosis in the presence of La(III) also occurred in human cells. These findings indicate that extracellular AGPs act as conserved CME cargo receptors, thus challenging the current paradigm about endocytosis of extracellular cargoes.

Declines in honey bee populations represent a worldwide concern. The widespread use of neonicotinoid insecticides has been one of the factors linked to these declines. Sublethal doses of a neonicotinoid insecticide, imidacloprid, has been reported to cause olfactory learning deficits in honey bees via impairment of the target organ, the brain. In the present study, olfactory learning of honey bees was compared between controls and imidacloprid-treated bees. The brains of imidacloprid-treated and control bees were used for comparative transcriptome analysis by RNA-Seq to elucidate the effects of imidacloprid on honey bee learning capacity. The results showed that the learning performance of imidacloprid-treated bees was significantly impaired in comparison with control bees after chronic oral exposure to imidacloprid (0.02 ng/μl) for 11 days. Gene expression profiles between imidacloprid treatment and the control revealed that 131 genes were differentially expressed, of which 130 were downregulated in imidacloprid-treated bees. Validation of the RNA-Seq data using qRT-PCR showed that the results of qRT-PCR and RNA-Seq exhibited a high level of agreement. Gene ontology annotation indicated that the oxidation-reduction imbalance might exist in the brain of honey bees due to oxidative stress induced by imidacloprid exposure. KEGG and ingenuity pathway analysis revealed that transient receptor potential and Arrestin 2 in the phototransduction pathway were significantly downregulated in imidacloprid-treated bees, and that five downregulated genes have causal effects on behavioral response inhibition in imidacloprid-treated bees. Our results suggest that downregulation of brain genes involved in immune, detoxification and chemosensory responses may result in decreased olfactory learning capabilities in imidacloprid-treated bees.

International audience; Nosema ceranae infection induces energetic stress, malnutrition, and precocious foraging in Apis mellifera. This study investigated effects of N. ceranae infection on the gene expression, protein content, and enzyme activity in the hypopharyngeal gland of nurse bees. The 285 differentially expressed genes were found between N. ceranae-infected and control bees using RNA-Seq, and 279 were upregulated and 6 were downregulated in infected bees. The protein level was significantly lower in infected bees than in controls, implying protein dysmetabolism and energetic stress in infected bees. The ELISA test showed that the specific activity of amylase was significantly higher in infected bees than in controls. The elevated enzymic activities were accompanied by an increased expressed level of hemolymph juvenile hormone-binding protein-encoding gene in infected bees, suggesting the possibility of Nosema-infected nurse bees to engage in behaviors that are normally performed by foragers.

ObjectiveTo assess whether women of advanced age (≥35 years) with polycystic ovary syndrome (PCOS) have the same cumulative live birth rate (CLBR) as their age-matched controls with tubal factor infertility and to determine the influencing factors on the CLBRs of aged women.DesignA retrospective cohort study.Setting and PopulationA total of 160 women of advanced age (≥35 years) with PCOS and 1073 women with tubal factor infertility were included in our study. All patients underwent their first fresh cycles and subsequent frozen cycles within in one year in our centre from 2015 to 2020.MethodsTo determine independent influencing factors on the CLBRs of these aged patients, a multivariable Cox regression model of CLBR according to the transfer cycle type was constructed. Main outcome measure(s): CLBRs.ResultThe Cox regression model of the CLBRs indicated that there was no significant difference between the PCOS group and the tubal infertility group in terms of advanced age (HR, 0.95; 95% CI, 0.71-1.27, P=0.732). The CLBR significantly decreased for women of advanced reproductive age up to 37 years of age (HR, 0.46; 95% CI, 0.39-0.56, PPConclusionDespite the higher number of oocytes retrieved in PCOS patients, the reproductive window is not extended for PCOS patients compared with tubal factor infertility patients. Age, AMH and the number of oocytes retrieved play crucial roles in the CLBRs of patients of advanced age (≥35 years).

Cs-Salts of the Keggin-type phosphomolybdic acid with simultaneous doping of VO2+ and different transition metals are prepared, characterized and tested as catalysts for the oxidation of isobutane to methacrylic acid under isobutane-rich conditions. The results show that Cs2.0V0.3Cu0.2PMo12O40 catalyst with co-substituted VO2+ and Cu2+ in its secondary structure exhibits higher catalytic performance than those with co-doped VO2+ and other transition metals such as Fe, Ni and Ce. This difference is ascribed to the synergistic effect between Cu2+ and VO2+ only in the secondary structure. This synergistic effect is related to the charge transfer between Mo6+ in the Keggin anions and Cu2+ counter cation, which promotes the re-oxidation of the catalyst and consequently its catalytic activity.

The impact of polarization effect on the performance of ZnO/MgZnO quantum cascade detector (QCD) is investigated with different scattering mechanisms taken into account. The energy band structure and wave functions are achieved by self-consistent calculation of Schrodinger-Poisson equations considering the spontaneous and piezoelectric polarization effects. The polarization field in the well or barrier of the QCD is obtained by assuming continuity of the displacement vector and the electronic transport is determined by piezoelectric polarization induced piezoelectric scattering, LO-phonon scattering and some other scattering mechanisms. The results show that the polarization charges at the interface make a significant contribution to the confining potential, which reduces the dark current, and increases the detectivity. The peak responsivity drops only 6.37% from 57 to 400 K without apparent redshift and the detectivity can be significantly improved by increasing doping concentration. This work is beneficial for the ZnO/MgZnO QCD design.

Vitronectin-like protein (VN) is widely found outside plant plasma membranes. The VN molecular surface contains a large number of active groups that combine strongly with rare earth elements (REEs), which means that VN is a preferential binding target for REEs exhibiting their toxic effects, but the toxicological mechanism remains unknown. This study used transmission electron microscopy, circular dichroism, fluorescence spectrometry, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, and calculational chemistry (homology modeling, molecular dynamics simulation and quantum chemical calculation) to preliminarily investigate the effect of lanthanum [La(III)] as an REE, on the structure of VN and its toxicological mechanism. The results showed that low-concentration La(III) could cause micro-interference to the VN molecular structure through weak interactions, such as electrostatic attraction. High-concentration La(III) formed stable complexes with VN, which changed the average binding energy and electron cloud density of VN, loosened the molecular structure and increased the disorder of VN molecule. The results of building a 3D model of VN and simulating the interaction between La(III) and VN using calculational chemistry showed that La(H2O)73+ in solution could coordinately bind to the carboxyl-/carbonyl-O groups in the negatively charged areas on the VN molecular surface. Furthermore, one or more strong H-bonds were formed to enhance the stability of the La(H2O)73+-VN complexes. In summary, low La(III) concentrations could cause micro-interference to the VN molecular structure, whereas high La(III) concentrations could coordinately bind to VN to form stable La-VN complexes, which destroyed the molecular structure of VN; thus the toxicological basis by which La(III) exhibits its toxic effects is its binding to VN.

Rare earth elements [REE(III)] increasingly accumulate in the atmosphere and can be absorbed by plant leaves. Our previous study showed that after treatment of REE(III) on plant, REE(III) is first bound by some extracellular molecules of plant cells, and then the endocytosis of leaf cells will be initiated, which terminates the endocytic inertia of leaf cells. Identifying the extracellular molecules for binding REE(III) is the crucial first step to elucidate the mechanism of REE(III) initiating the endocytosis in leaf cells. Unfortunately, the molecules are unknown. Here, cerium(III) [Ce(III)] and Arabidopsis served as a representative of REE(III) and plants, respectively. By using interdisciplinary methods such as confocal laser scanning microscopy, immune-Au and fluorescent labeling, transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy, circular dichroism spectroscopy, fluorescent spectrometry and molecular dynamics simulation, we obtained two important discoveries: first, the arabinogalactan proteins (AGP) inside leaf cells were sensitively increased in protein expression and recruited onto the plasma membrane; second, to verify whether AGP can bind to Ce(III) in the acidic environment outside leaf cells, by choosing fasciclin-like AGP11 (AtFLA11) as a representative of AGP, we found that Ce(III) can form stable [Ce(H2O)7](III)-AtFLA11 complexes with an apparent binding constant of 1.44 × 10−6 in simulated acidic environment outside leaf cells, in which the secondary and tertiary structure of AtFLA11 was changed. The structural change in AtFLA11 and the interaction between AtFLA11 and Ce(III) were enhanced with increasing the concentration of Ce(III). Therefore, AtFLA11 can serve as Lewis bases to coordinately bind to Ce(III), which broke traditional chemical principle. The results confirmed that AGP can be the possible extracellular molecules for binding to exogenous Ce(III) outside leaf cells, and provided references for elucidating the mechanism of REE(III) initiating the endocytosis in leaf cells.

Plants can uptake and accumulate rare earth elements (REEs) from the ecosystem. Responses of plants to REEs have attracted researchers’ attention for nearly one hundred years, but the mechanisms of their responses are largely unknown. Identifying the binding target of REEs and its mode of interaction with the target will be the key to reveal the cellular responsive mechanisms. In this study, La(III) as a representative of REEs, we found excitedly that vitronectin-like protein (VN) was strongly expressed in cells and migrated towards the plasma membrane with increasing concentrations of La(III), raising the possibility that VN acts as a defense mechanism to resist the entry of La(III) into cells. Interestingly, VN is an anchoring site and binding target for La(III) on the plasma membrane of Arabidopsis leaf cells. In this process, La(III) as a Lewis acid is anchored by VN as a Lewis base to form La(III)-VN coordination complexes. Therefore, VN is a first line of defense against La(III) stress and enhances plant tolerance to REEs. Our findings provide new insight into the cellular responsive mechanisms of plants to REEs.

The high-field electron transport properties of ZnMgO/ZnO heterostructures considering multisubband conduction were systematically investigated with an ensemble Monte Carlo program developed by us. Electronic band structures were obtained by first-principles calculations using density functional theory, which provides more accurate parameters to calculate the electronic states and transport characteristics of 2-D electron gas. Wave functions and energy levels describing the subband structure were achieved to determine the 2-D scattering rates by solving the Schrodinger and Poisson equations self-consistently. The highest electron mobility gained at room temperature was approximately $4.23\times 10^{\mathrm {2}}$ cm2/Vs. The negative differential mobility was observed with a threshold electric field of approximately 80 kV/cm. The peak drift velocity of the Zn0.694Mg0.306O/ZnO heterostructure at 200 KV was about $2.011\times 10^{8}$ cm/s. This paper benefits the development of high-performance ZnMgO/ZnO heterostructure devices.

The geometric structures of ZnO, yttrium doped ZnO (YZO), ZnO with Zn interstitial (ZIO) and yttrium doped ZnO with Zn interstitial (YZIO) systems are investigated using the first-principle method based on density functional theory. The results show that doping yttrium ions can decrease the formation energy of Zni defects adjacent to yttrium ions. The electronic structures and absorption spectra of these systems are further obtained after revising the value of bandgap. Compared with ZnO, YZO and ZIO systems, there is an impurity level (Er) near the center of the forbidden band in YZIO, which will enhance the luminescence peak in yellow region. Besides, the bandgap of YZIO will increase with the increase of yttrium doping concentration, which suggests that the UV emission of YZIO would have a blue shift. In addition, the absorption property of YZIO system is also improved in both the visible and UV regions, which can be used in converting solar energy into electricity.

Aiming at developing a highly active electrocatalyst with high platinum utilization efficiency, we report a facile synthesis of carbon supported Pd3Au@Pt electrocatalyst by chemical reduction of K2PtCl4, K2PdCl4, and aq NaAuCl4 with ascorbic acid (AA) under ambient conditions in the absence of surfactants. The resultant Pd3Au@Pt/C electrocatalyst comprises of a thin platinum layer less than 1 nm in thickness deposited on the outer surface of Pd3Au alloy core with an average diameter of 3.4 nm. Remarkably, Pd3Au@Pt/C exhibited a high mass activity (MA, 939 mAmg(Pt)(-1)) toward oxygen reduction reaction (ORR), which is 4.6 times that of commercial Pt/C (203 mAmg(Pt)(-1)). The durability of Pd3Au@Pt/C is close to that of commercial Pt/C. According to X-ray diffraction (XRD) patterns, the lattice constant of the Pd3Au alloy supported on carbon is determined to be 3.950 angstrom close to yet slightly larger than that of Pt/C (3.920 angstrom), inducing a lateral tensile strain of the platinum shell. Meanwhile, electrons from the Pd3Au core appear transferred to the platinum shell as evidenced by X-ray photoelectron spectroscopy (XPS). We propose that the lateral tensile strain (geometric effect) and the electron transfer (electronic effect) as well as the high platinum utilization efficiency have contributed to the significantly improved electrocatalytic activity of Pd3Au@Pt/C. The coexistence of the lateral tensile strain and the electron transfer in the electrocatalyst with a high ORR activity has not been reported prior to this study.

After rare earth elements [REE(III)] are anchored outside of the plasma membrane, REE(III) break plant evolution to initiate leaf cell endocytosis, which finally affects plant growth. However, the molecule for anchoring REE(III) in the acidic environment outside of the plasma membrane is not clear, which is crucial for exploring the mechanism of REE(III) breaking plant evolution. Here, lanthanum(III) [La(III)] and terbium(III) [Tb(III)] were respectively served as a representative of REE(III) without and with f electrons, and Arabidopsis was served as a representative of plants, cellular and molecular basis for arabinogalactan proteins (AGP) anchoring REE(III) outside of the plasma membrane was investigated. By using interdisciplinary methods, when REE(III) initiated leaf cell phagocytosis, we observed the increase in the expression of AGP and their migration to the outside of the plasma membrane. In the acidic environment outside of the plasma membrane, Tb(III) formed more stable Lewis acid-base [REE(III)-AGP] complexes with a higher apparent binding constant (1.51 × 10−6) than La(III) (1.24 × 10−6). In REE(III)-AGP complexes, the bond lengths of REE(III)-O were in normal range and H-bonds were strong H-bonds. The formation of REE(III)-AGP complexes sequentially disturbed the secondary and tertiary structure of AGP, which were enhanced with increasing the concentration of REE(III), and Tb(III) caused stronger structural changes than La(III). Hence, AGP could be molecules for anchoring REE(III) outside of the plasma membrane. The results of this study are direct imaging of how lanthanides break the normal evolution of plants, and can serve as an important guidance for investigating mechanism of lanthanides in organisms.

The environmental safety of cerium (Ce) applications in many fields has been debated for almost a century because the cellular effects of environmental Ce on living organisms remain largely unclear. Here, using new, interdisciplinary methods, we surprisingly found that after Ce(III) treatment, Ce(III) was first recognized and anchored on the plasma membrane in leaf cells. Moreover, some trivalent Ce(III) was oxidized to tetravalent Ce(IV) in this organelle, which activated pinocytosis. Subsequently, more anchoring sites and stronger valence-variable behavior on the plasma membrane caused stronger pinocytosis to transport Ce(III and IV) into the leaf cells. Interestingly, a great deal of Ce was bound on the pinocytotic vesicle membrane; only a small amount of Ce was enclosed in the pinocytotic vesicles. Some pinocytic vesicles in the cytoplasm were deformed and broken. Upon breaking, pinocytic vesicles released Ce into the cytoplasm, and then these Ce particles self-assembled into nanospheres. The aforementioned special behaviors of Ce decreased the fluidity of the plasma membrane, inhibited the cellular growth of leaves, and finally, decreased plant yield. In summary, our findings directly show the special cellular behavior of Ce in plant cells, which may be the cellular basis of plant yield reduction induced by environmental Ce.

Structural properties along with the electronic and optical properties of intrinsic 3C-SiC and Co doped 3C-SiC are calculated using the first principles method based on the density functional theory. The calculated results show that the Fermi level locates at the valence band maximum in the pure 3C-SiC, while it shifts to the conduction band and exhibits metal-like characteristic after Co atoms are introduced into the SiC supercell. The calculated electronic structures indicate that the number of the energy levels in upper valence band substantially increased after Co doping, which is attributed to the Co-3d states. The optical property calculation suggests that the intensity of the photoluminescence (PL) spectrum is determined by the bandgap and the location of PL peak is associated with the optical absorption.

The effect of temperature on a ZnO/Mg0.3Zn0.7O quantum cascade detector (QCD) in the mid-infrared region is investigated with consideration of bound-to-bound electronic-transport processes in the dark and under illumination. The temperature-dependent band structures of the QCD system, which comprises four quantum wells and five barriers in one period, are numerically calculated. The electronic transition is obtained with a standard electron-optical phonon Hamiltonian, and the photon absorption is described by the two-dimensional absorption coefficient. The responsivity of the ZnO/Mg0.3Zn0.7O QCD shows a good temperature stability without an obvious redshift, and the peak responsivity decreases by only 14% when the temperature increases from 50 to 300 K.

For high-speed optical communication applications, the bandwidth of photodetector would be a key limitation. In this work, the bandwidth property of MgZnO-based Metal-Semiconductor-Metal (MSM) photodetector considering RC and transit limitations is investigated on the basis of the series and enhanced gain peaked photodetector circuits proposed by us with different finger widths. To ensure the accuracy of parameters, the high-filed transportation characteristics of MgZnO are investigated by a three-valley ensemble Monte Carlo simulation combined with first principle calculations. The results show that the gain peaking technique, especially the enhanced gain peaking, can improve the bandwidth of MgZnO MSM photodetector to a maximum value of 61.28 GHz, corresponding to a bandwidth enhancement of 49% without undesired effects. Three-dimensional electromagnetic computation is further performed to design and simulate the on-chip-inductor. The value of the simulated inductor is approximately 0.0529 nH, which is in good agreement with the designed value of 0.0569 nH. This work benefits the development of high speed MgZnO MSM photodetector.