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Root-lesion nematodes, Pratylenchus spp., are economically important pathogens because of their detrimental and economic impact on a wide range of crops. In August 2018, two samples of both roots and rhizosphere soil were collected from a corn field in Liangyuanqu of Shangqiu city, Henan Province, China. Root-lesion nematodes were recovered from the roots and soil samples using the modified Baermann funnel extraction method. Both the morphological characters and molecular analysis of the internal transcribed spacer (ITS) and D2-D3 expansion region of 28S ribosomal RNA sequences confirmed that the root-lesion nematode population collected from corn in this study was P. neglectus. Phylogenetic analyses showed that this isolate formed a highly supported clade with other P. neglectus isolates. To the best of our knowledge, this is the first report of P. neglectus on corn in Henan Province of China. This study reports the first partial sequences of 28S D2-D3 region of P. neglectus on corn in China. Due to the great harmfulness of root-lesion nematodes to corn, care should be taken to prevent the spread of P. neglectus to other regions in China. At the same time, further study on the biological characteristics of P. neglectus is needed, which will be helpful to develop corresponding management and control strategies.

To identify molecular markers for early diagnosis and new targets for treatment of cervical squamous cell carcinoma. Our study involved 52 carcinoma tissues that were confirmed pathologically as cervical squamous cell carcinoma (CSCC) at the Fourth Hospital of Hebei Medical University in 2021. We obtained 36 control specimens from patients who had undergone hysterectomy for benign uterine diseases in 2021, with no cervical lesions as confirmed by pathology. Total RNA was extracted from all the samples. Reverse transcription and quantitative real-time PCR were performed. Immunohistochemical staining for interferon-stimulated gene 15 (ISG15) protein was performed. Descriptive analyses including mean and standard deviation were used to compare different groups. For data that do not conform to normal distribution, we use Wilcox rank sum test to make statistics to compare different groups with the median and interquartile. Mann Whitney U test was used to compare non-parametric continuous data, and categorical variables were analyzed using chi-square test. Receiver operating characteristic (ROC) curve was used to evaluate the possibility of using ISG15 as a new biomarker for cervical squamous cell carcinoma. Compared with normal cervical tissues, mRNA expression of ISG15 in cervical cancer tissues was significantly lower (P<0.01); mRNA expression was significantly lower in patients with nerve invasion (P<0.05). Difference in ISG15 protein expression was statistically significant (no expression/low expression) in the cancer samples compared to normal tissues (P<0.01). The area under ROC curve was 0.810 (P<0.001) and the sensitivity and specificity were 75% and 54%, respectively. Spearman's correlation analysis showed that ISG15 mRNA was positively correlated with protein expression (r=0.358, P=0.001). Deficiency of ISG15 may be associated with the occurrence and progression of CSCC. It could be used as a potential tumor marker in research and treatment of CSCC. [ABSTRACT FROM AUTHOR]

This paper studies a class of credibilistic optimization (CO) problems, in which a convex objective is minimized subject to ambiguous credibilistic constraints. The considered CO problem is usually computational intractable. Our purpose in this paper is to discuss the robust counterpart approximations of ambiguous credibilistic constraints. Under mild assumptions, the closed property about the feasible region of credibilistic constraint is discussed. Using the obtained results, this paper deals with the robust counterpart approximations of credibilistic constraints under two types of ambiguity sets of possibility distributions. The first type is exponential function-based ambiguity set of possibility distribution, while the second type of ambiguity set is a particular case of the first one, and it is based on range and expectation information of fuzzy variables. The developed approximation techniques are capable to utilize the knowledge of ambiguity sets of possibility distributions when building distribution uncertainty-immunized solutions. As a result, the obtained safe approximations of ambiguous credibilistic constraints are computationally tractable convex/linear constraints. To apply the proposed approximation approach, a portfolio optimization problem is addressed, in which the investor is to find a portfolio to maximize the value-at-risk of his total return under the support and expectation information of uncertain returns. We use two types of robust counterpart approximations to credibilistic constraints. The computational results support our arguments. [ABSTRACT FROM AUTHOR]

Microwave reflectometry diagnostics have been widely used to measure density profiles in fusion plasma. However, the high sensitivity of the diagnostics to plasma turbulence often results in large radial deviations in the edge density profile and causes difficulty in profile evaluation. To improve the performance of profile evaluation, a modified RANdom SAmple Consensus (RANSAC) method has been applied to fit the density profiles measured by reflectometry on the experimental advanced superconducting tokamak. Compared with the traditional least-squares method, the modified RANSAC method is much more efficient and robust in fitting the experimental profiles. Furthermore, a combination of RANSAC and a genetic algorithm (GA-RANSAC) is used to further optimize the profile evaluation procedure. The results show that this GA-RANSAC method yields better performance and stabler convergence than the modified RANSAC alone. [ABSTRACT FROM AUTHOR]

A series of ZnxFe3-xO4 (ZFO, x=0.4) thin films were epitaxially deposited on single-crystal (001)-SrTiO3 (STO) substrates by radio frequency magnetron sputtering. The anomalous thickness-dependent strain states of ZFO films were found, i.e., a tensile in-plane strain exists in the thinner ZFO film and which monotonously turns into compressive in the thicker films. Considering the lattice constant of bulk ZFO is bigger than that of STO, this strain state cannot be explained in the conventional framework of lattice-mismatch-induced strain in the hetero-epitaxial system. This unusual phenomenon is proposed to be closely related to the Volmer-Weber film growth mode in the thinner films and incorporation of the interstitial atoms into the island's boundaries during subsequent epitaxial growth of the thicker films. The ZFO/STO epitaxial film is found in the nature of magnetic semiconductor by transport measurements. The in-plane magnetization of the ZFO/STO films is found to increase as the in-plane compressive strain develops, which is further proved in the (001)-ZFO/PMN-PT film where the film strain state can be in situ controlled with applied electric field. This compressive-strain-enhanced magnetization can be attributed to the strain-mediated electric-field-induced in-plane magnetic anisotropy field enhancement. The above results indicate that strain engineering on magnetic oxide semiconductor ZFO films is promising for novel oxide-electronic devices. [ABSTRACT FROM AUTHOR]

The ferroelectric properties of the BiFeO3/La0.625Ca0.375MnO3 (BFO/LCMO) heterostructures were investigated using different bottom electrode configurations at different magnetic fields and temperatures. It is found that the apparent coercive voltage (Vac) increases linearly with the increase of LCMO resistances for different electrodes, and the extrinsic relative contribution from different LCMO electrodes to the variation of Vac caused by magnetic field can be quantitatively analyzed based on the scenario of voltage drop model. The magnetic field and temperature dependences of the heterostructure coercive voltage (Vac0) obtained by subtracting the voltage drop on LCMO from Vac are closely related to the interface behaviors. These findings not only further elucidate the physics of magnetoelectric coupling in multiferroic heterostructures but also are helpful for designing artificial prototype device. [ABSTRACT FROM AUTHOR]

The Experimental Advanced Superconducting Tokamak (EAST) research program concentrates on demonstrating steady-state high-performance H-mode operations with ITER-like tungsten divertor. Calorimetry was applied to actively water-cool the plasma facing components (PFCs) by increasing the water temperature for power balance investigation. Considering the energy balance of EAST long-pulse high-performance discharges with upper single null (USN) configuration, thus far, approximately 78% of the injected energy could be accounted for. The method of estimation of heat flux on upper tungsten divertor target with a high time- and spatial-resolved infrared camera has been developed, and the sum of its heat load was found to be significantly consistent with that measured through calorimetry. The record longest steady-state H-mode plasma #73 999 was sustained for up to 101.2 s with net injected energy exceeding ∼0.25 GJ in the USN configuration. Heat load analysis of this discharge using calorimetric measurement indicates that the modification of heat load distribution was observed and this was induced by a slight change in the magnetic configuration. Not all temperature increments in the five cooling water modules reached the saturated state for the 100 s level discharge, which means that 100 s timescales are insufficient as compared to the thermal transport timescale in the targeted PFCs. The heat load on the tungsten divertor targets is not evenly distributed with the ratio of ∼2 in favour of the outer divertor.The experimental results and analysis of the physics involved in these USN configuration discharges are reported and discussed. [ABSTRACT FROM AUTHOR]

Street trees are common features and important assets in urban scenes. They are huge in numbers and are constantly changing, thus are difficult to monitor on a regular basis. A method of automatic extraction and dynamic analysis of street trees based on mobile LiDAR data is proposed. First, ground and low objects are filtered from the point clouds. Then, based on a geometric tree model and semantic information, each tree point cloud is extracted, and geometrical parameters such as location, trunk diameter, trunk structure line, tree height, crown width, and crown volume of each tree is obtained. A dynamic analysis combined with the growing characteristics of trees is conducted to compare and analyse the street trees from different epochs, in order to understand whether the trees have grown or been pruned, replanted, or displaced. The proposed algorithm was tested on three epochs of mobile LiDAR data, obtained in 2010, 2016 and 2018, respectively. Experimental results showed that the proposed method was able to accurately detect trees and extract tree parameters for detailed dynamics analysis. [ABSTRACT FROM AUTHOR]

Viscous flow around two unequal cylinders is simulated by solving the non-dimensional Navier–Stokes equations. A total of 13 two-dimensional numerical cases are carried out in this study for the flow fields around two adjacent cylinders at Re= 200. The ratio of d/D is equal to 0.25 (d and D are the diameters of the secondary and primary cylinders, respectively), the distance between two cylinders is kept as a constant (G = D), and the angle between them ranges from θ = 0° to θ = 180°. Firstly, six types of wake patterns are proposed and detailedly analyzed for the first time in this study. It is observed that the vortex shedding pattern is dependent on the position of the secondary cylinder. Secondly, this paper systematically analyzes the gap flow features between two cylinders for various angles, including the gap-flow strength, the deflection direction and the deflection mechanism. Additionally, this study also discusses in detail the variation characteristics of the drag coefficient, the lift coefficient, the Strouhal number and the time-averaged pressure. It is found that the drag and lift coefficients share a similar variation regularity, while the Strouhal number presents an opposite tendency with the change of the angle. [ABSTRACT FROM AUTHOR]

Relativistic mirrors can be realized with strongly nonlinear Langmuir waves excited by intense laser pulses in underdense plasma. On reflection from the relativistic mirror, the incident light affects the mirror motion. The corresponding recoil effects are investigated analytically and using particle-in-cell simulations. It is found that if the fluence of the incident electromagnetic wave exceeds a certain threshold, the relativistic mirror undergoes a significant back reaction and splits into multiple electron layers. The reflection coefficient of the relativistic mirror and the factors of electric field amplification and frequency upshift of the electromagnetic wave are obtained. [ABSTRACT FROM AUTHOR]

Conversion electron Mossbauer spectroscopy (CEMS) and x-ray diffraction are used to discuss a series of rf-reactively sputtered FeAlN thin films with the goal of gaining insight into the origins of their uniaxial magnetic anisotropy (UMA). UMA and its thermal stability are therefore concluded to have a correlation with the local environment of the Fe structure induced by N doping.

As a platform with the advantages of safety, wide altitude range and long flight time, tethered balloon has been used in archaeology, coastal, island mapping and other related fields. Tethered balloon is tied to the mooring system by tether rope, and often moves in a small range with the airflow, resulting in a very close distance between the camera stations. Due to the small base-to-height ratio, failure of relative orientation or poor quality of point cloud tend to appear frequently. In this paper, a mapping system for tethered balloon is introduced which consists of a wide-angle camera, two auxiliary orientation cameras, and a dual GNSS/IMU system. The wide-angle camera combined by five cameras provides a larger observation range. Two auxiliary orientation cameras installed at the end of extension rods are designed to increase the baseline. The system should be operated during the taking-off, hovering and landing stages of the tethered balloon, so as to take images of different altitudes. The system has been adopted in the first experimental flight in 2018 to perform island topographic survey. Data processing method was applied to test the effect of the system. The method that choosing wide-angle images of different heights, and auxiliary images at low-altitude can be used for aerial triangulation successfully, and obtain point cloud with good quality. The results showed that by adding auxiliary cameras and taking images of different heights for data processing, the problem of small intersection angle could be overcome to some extent. [ABSTRACT FROM AUTHOR]

Ionic liquid (IL) gating of functional oxides has drawn significant attention, since it can provide reversible changes in carrier concentration (~1014 cm $^{-2}$) at the interface, permitting the manipulation of electrical and magnetic properties of oxide films with low voltages. In this paper, we demonstrated the electric-field manipulation of transport properties in the dilute magnetic semiconductor of Zn0.98Mn0.02O (MZO), using an electric-double-layer transistor geometry through the IL electrolyte gating. The MZO layer exhibited reversible control of resistance up to 33% at 230 K. Moreover, magnetoresistance (MR) measurements revealed the influence of applied gate voltage ($V_{g}$) on the magnetotransport behavior, which exhibited a positive MR in the low-field region and a negative MR in high magnetic field (up to 9 T). An increase in low-field positive MR (<1 T) upon switching $V_{g}$ from −2 to 2 V implied an enhanced ferromagnetic state of MZO due to an increased electron carrier concentration. The results demonstrated that a controllable carrier concentration by electric-field effect played an important role in the manipulation of magnetism in MZO. [ABSTRACT FROM AUTHOR]

Brillouin light scattering from thermal spin waves has been exploited to investigate the thickness dependence of magnetic anisotropy of Ni films, with thickness in the range 7-35 nm, grown by electrodeposition onto either (011)- or (001)-GaAs substrates. In the former case, Ni films exhibit a well-defined in-plane uniaxial anisotropy induced by the symmetry of the substrate. In the case of the (001)-GaAs substrate, instead, the magnetic anisotropy results from a combination of both a fourfold and a twofold contribution. The physical mechanisms responsible for the observed anisotropy, as well as its dependence on film thickness, are discussed in detail. [ABSTRACT FROM AUTHOR]

We demonstrate how epitaxial FM (Ni) films can be grown by ECD directly onto GaAs(001) without outdiffusion or surface segregation of As or Ga. The thickness dependence of electrical and magnetic properties (saturation magnetic moment) verify the good quality of the layers and indicate that electrochemical deposition is a suitable candidate for the growth of epitaxial Ni films with sharp interfaces on GaAs(001). X-ray photoelectron spectroscopy (XPS) analysis on electroplated (epitaxial) Ni films showed no interdiffusion for annealing up to 250 °C. Annealing at higher temperatures, up to 350 °C, significantly increases both the As outdiffusion and the Schottky barrier heights, which indicates the correlation between intermixing and the diode quality. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report the epitaxial growth of high quality Fe thin films on both n-type GaAs(001) and GaAs(011) substrates using electrochemical deposition. X-ray diffraction shows Fe(001)[110]//GaAs(001)[110] and Fe(011)[100]//GaAs(011)[100] as the primary epitaxial relations similarly to Fe films grown by molecular-beam epitaxy. The structural quality depends on the composition of the plating solution. The Hc values of these films are around 30–100 Oe. The 4πMs value is about 20–21 kG. In-plane angular ferromagnetic resonance measurements showed crystalline anisotropy for both the Fe(001) and Fe(011) films which is superimposed by a substrate induced uniaxial anisotropy for the Fe(011) layers. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Chinese Fusion Engineering Test Reactor (CFETR) is a new superconducting tokamak device being designed in China, which aims at bridging the gap between ITER and DEMO, where DEMO is a tokamak demonstration fusion reactor. Two diagnostic cases, ITER-like case and towards DEMO case, have been considered for CFETR early and later operating phases, respectively. In this paper, some preliminary consideration of ITER-like case will be presented. Based on ITER diagnostic system, three versions of increased complexity and coverage of the ITER-like case diagnostic system have been developed with different goals and functions. Version A aims only machine protection and basic control. Both of version B and version C are mainly for machine protection, basic and advanced control, but version C has an increased level of redundancy necessary for improved measurements capability. The performance of these versions and needed R&D work are outlined. [ABSTRACT FROM AUTHOR]

Based on credibilistic value-at-risk (CVaR) of regular fuzzy variable, we introduce a new CVaR reduction method for type-2 fuzzy variables. T h e reduced fuzzy variables are characterized by parametric possibility distributions. We establish some useful analytical expressions for mean values and second order moments of common reduced fuzzy variables. T h e convex properties of second order moments with respect to parameters are also discussed. Finally, we take second order moment as a new risk measure, and develop a mean-moment model to optimize fuzzy portfolio selection problem s. According to the an alytical form ulas of second order moments, the mean-moment optimization model is equivalent to parametric quadratic convex programming problem s, which can be solved by general-purpose optimization software. The solution results reported in the numerical experiments demonstrate the credibility of the proposed optimization method. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To observe the heart rate turbulence (HRT) in patients with masked hypertension (MH), and white-coat hypertension (WCH). PATIENTS AND METHODS: Patients were classified on the basis of clinic and 24h ambulatory blood-pressure monitoring: essential hypertension (H, n = 32), masked hypertension (MH, n=26), white-coat hypertension (WCH, n = 29) and normotension (NT, n = 30). For each subject, we recorded 24 hours holter monitoring electrocardiogram, calculated the turbulence onset (TO) and turbulence slope (TS) and compared the differences. RESULTS: Compared with NT controls, the differences of TO and TS in the patients with EH, MH and WCH were statistically significant (p < 0.01). No significant differences were found between the EH, MH and WCH groups. CONCLUSIONS: The HRT in EH, MH and WCH patients is significantly lower, when their autonomic nerve function is damaged. [ABSTRACT FROM AUTHOR]

Background:The cross-talk of hepatocellular carcinoma (HCC) cells and abnormal metabolic signals in peritumoral microenvironment modifies our knowledge of hepatocarcinogenesis. As an indispensable modulator of various stresses, the clinical significance of heat-shock transcription factor-1 (HSF1) in HCC microenvironment has never been defined.Methods:Hepatocellular carcinoma and matched peritumoral liver tissues (n=332) were semiquantitatively analysed for HSF1 expression, followed by correlation with clinicopathological parameters (patient outcomes). Moreover, the effects of HSF1 deficiency in L02 on monocarboxylate transporter-4 (MCT4) and HCC cells' colonisation and proliferation were investigated.Results:High expression of HSF1 in peritumoral tissue but not in HCC tissue was associated with poorer overall survival (OS) and time to recurrence (TTR), especially early recurrence (ER), which was further reconfirmed in validation cohort. Multivariate analysis showed that prognostic performance of peritumoral HSF1 was independent of other clinicopathological factors (hazard ratio for OS=2.60, P=0.002, for TTR=2.52, P<0.001). Notably, downregulation of HSF1 in L02 decreased MCT4 expression significantly. The supernatant from L02-shRNA-HSF1 in hypoxia, NOT normoxia condition, inhibited HCC cell colonisation and proliferation. Moreover, the combination of peritumoral HSF1 and MCT4 was the best predictor for ER and OS.Conclusion:High peritumoral HSF1 expression can serve as a sensitive 'readout' for high-risk HCC ER, and could be a potential metabolic intervention target following curative resection. [ABSTRACT FROM AUTHOR]

The ferroelectric polarization dependent bipolar and conductive filament related unipolar resistive switching behaviors are investigated systematically in Au/BiFe0.95Mn0.05O3/La5/8Ca3/8MnO3 heterostructure. The results show that after conductive filaments are formed, the ferroelectric state previously polarized will keep almost unchanged. By combining the two resistive switching mechanisms together under appropriate programming conditions, a tri-state-like resistive switching behavior is realized, finding effective routes in designing high-density storage. According to these distinctive characteristics, a prototype memory device with secure information storage is properly designed as an example of promising applications. [ABSTRACT FROM AUTHOR]

Traversing voxels along a three dimensional (3D) line is one of the most fundamental algorithms for voxel-based applications. This paper presents a new 6-connectivity integer algorithm for this task. The proposed algorithm accepts voxels having different sizes in x, y and z directions. To explain the idea of the proposed approach, a 2D algorithm is firstly considered and then extended in 3D. This algorithm is a multi-step as up to three voxels may be added in one iteration. It accepts both integer and floating-point input. The new algorithm was compared to other popular voxel traversing algorithms. Counting the number of arithmetic operations showed that the proposed algorithm requires the least amount of operations per traversed voxel. A comparison of spent CPU time using either integer or floating-point arithmetic confirms that the proposed algorithm is the most efficient. This algorithm is simple, and in compact form which also makes it attractive for hardware implementation. [ABSTRACT FROM AUTHOR]

Voxel traversing along a line in a uniformly divided voxel space is frequently needed in different applications of computer graphics. The paper presents a new integer one-pass algorithm for this problem. In 2D, the proposed approach is based on a modification of the well-known Bresenham algorithm. The algorithm is then extended in 3D where a special case may occur. It is characterized by a simple discriminator. A derivation for this discriminator given in the paper confirms that all calculations can be realized using only integer arithmetic. In this way, the accumulation of rounding errors is completely eliminated, and a robust and compact implementation can be easily achieved. One of the main advantages of the proposed algorithm is that it visits 1–3 voxels during each iteration thus assuring its efficiency. The algorithm has been compared with other algorithms for voxel traversing by measuring spent CPU time. For comparison, Cleary & Wyvill's, Amanatides & Woo's, and Code-based algorithm have been used. The proposed algorithm is faster than the referenced algorithms. [ABSTRACT FROM AUTHOR]

A new human hepatocellular carcinoma (HCC) cell line with a highly metastatic potential was established from subcutaneous xenograft of a metastatic model of human HCC in nude mice (LCI-D20) by means of alternating cell culture in vitro and growth in nude mice. The line, designated MHCC97, has been cultivated for 18 months and subcultured for more than 90 passages. The line was showed to be of human origin by karyotype analysis. The cells were either grown as compact colonies (in clusters) or as a monolayered sheet with about 31 h of population-doubling time, exhibited typical malignant epithelial in morphology and were positive for a-fetoprotein (AFP). Flow cytometric analysis of the cell DNA content showed an aneuploid pattern, and its index was 1.5 as compared to that of normal human peripheral blood lymphocytes. Karyotypic analyses of G- and C-banding techniques revealed that all cells presented chromosome abnormalities in number and structure. The number of cell line MHCC97 chromosome ranged from 59 to 65 with a modal number of 60 and 61. At least two common chromosome markers, i(1q) and der(4)t(4;?)(4pter→q35::?), were present in all cells, and deletion of Y chromosome also occurred in all cells. The subcutaneous and intrahepatic xenografts were formed and metastatic lesions in lungs were found after the cells were inoculated into nude mice. The rate of metastasis to lungs was 100% using orthotopic inoculation. Reverse transcription polymerase chain reaction products revealed positive expressions of integrin α[SUB5] and β[SUB1], urokinase type plasminogen activator receptor) (uPAR), vascular endothelial growth factor and nm23-H1 mRNAs of cell line MHCC97. Immunostaining of c-Met, uPAR showed strongly positive in both subcutaneous xenografts and lung metastatic lesions; while positive in xenografts and negative in metastatic lesions for integrin α[SUB5], β[SUB1]. E-cadherin and P53 was not expressed either in xenograft or in the... [ABSTRACT FROM AUTHOR]

We compared the strength of a new step-cut technique for flexor tendon repair with that of the widely used Kessler-Tajima technique, giving special attention to the relative contributions of the core and epitendinous sutures. 36 flexor digitorum profundus tendons from human cadavers were used. Corresponding digits from the same donor were paired, and the two tendons of each pair were placed in the Kessler-Tajima and step-cut groups, respectively. Each group had three subcategories of repair: (1) core repair alone; (2) epitendinous repair alone; and (3) full repair. In the Kessler-Tajima repair, the core stitch contributed more to ultimate tensile strength, while the epitendinous stitch contributed more to gap formation resistance. In the step-cut repair, however, the epitendinous stitch contributed more to both measures of strength. The full step-cut repair was 65% stronger in resisting gap formation and had 84% more ultimate tensile strength than the full Kessler-Tajima repair. We attribute the greater strength of the step-cut repair to the additional number of epitendinous loops, which lie perpendicular to the long axis of the tendon. [ABSTRACT FROM PUBLISHER]

We present detailed experimental results of the temperature dependence of continuous wave and time-resolved photoluminescence (PL) spectroscopy in self-assembled InAs/GaAs quantum dot and quantum ring nanostructures. A dramatic increase in PL decay time of the excited and ground states is observed in InAs quantum rings at high temperature. We speculate that the longer PL lifetime in quantum rings is due to the interplay among the dark states, ground states, and the reduced wave function overlapping between electrons and holes. A rate equation model is proposed to interpret the observed temperature dependence of the ground state exciton lifetime. [ABSTRACT FROM AUTHOR]

The authors show that II-VI nanoribbons are capable of room-temperature lasing covering the complete spectral range from near infrared (NIR) to ultraviolet (UV). This is accomplished by simply using nanoribbons of two ternary compositions, namely, CdSXSe1-X and ZnYCd1-YS. Under optical pumping, CdSXSe1-X nanoribbons lase from NIR (710 nm) to green (510 nm) as X changes from 0 to 1, while ZnYCd1-YS nanoribbons lase from green (510 nm) to UV (340 nm) as Y varies from 0 to 1. Furthermore, lasing control shows fine-tuning via composition changes that overlap thermally induced tuning. This demonstrates that II-VI materials can enable lasing at any selected wavelength between 710 and 340 nm with continuous tuning capabilities. [ABSTRACT FROM AUTHOR]

Manganese (Mn) doping of ZnS nanoribbons was achieved by simple thermal annealing. Upon heating ZnS nanoribbons with MnS powder up to 700 °C, the intrinsic photoluminescence (PL) of the annealed nanoribbons disappeared and a new PL peak at 585 nm gradually emerged. Significantly, the annealing process induced no detectable change in the morphology and uniform hexagonal wurtzite 2H structure of the single-crystal ZnS nanoribbons. The PL peak at 585 nm is attributed to Mn dopant and confirms Mn incorporation in ZnS because (1) the peak appears only when ZnS ribbons were annealed with MnS, but does not appear without MnS, (2) its intensity increases with increasing annealing temperature, which is consistent with increased incorporation of Mn2+ ions, and (3) its position is similar to that of Mn-related emission in ZnS, and is independent of the measuring temperature and excitation power. This work demonstrates the capability of doping nanostructured materials by simple postannealing treatment. [ABSTRACT FROM AUTHOR]