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Alopecia areata is a common disease in dermatology. It is a localized non-inflammatory alopecia that occurs in the head. Its etiology is unclear, but it is thought to be related to a number of factors. At present, there are many methods of treatment with different curative effects. Fire needle acupuncture directly acts on skin lesions, dredges meridians, and regulates Qi and blood. It has a good curative effect. This paper reviews current research progress of fire acupuncture in the treatment of alopecia areata, in order to provide some diagnostic and treatment suggestions for the management of alopecia areata.

The phytohormone abscisic acid (ABA) is a central regulator of acclimation to environmental stress; however, its contribution to differences in stress tolerance between species is unclear. To establish a comparative framework for understanding how stress hormone signalling pathways diverge across species, we studied the growth response of four Brassicaceae species to ABA treatment and generated transcriptomic and DNA affinity purification and sequencing datasets to construct a cross-species gene regulatory network (GRN) for ABA. Comparison of genes bound directly by ABA-responsive element binding factors suggests that cis-factors are most important for determining the target loci represented in the ABA GRN of a particular species. Using this GRN, we reveal how rewiring of growth hormone subnetworks contributes to stark differences in the response to ABA in the extremophyte Schrenkiella parvula. Our study provides a model for understanding how divergence in gene regulation can lead to species-specific physiological outcomes in response to hormonal cues.

Photosynthesis in leaves generates fixed-carbon resources and essential metabolites that support sink tissues, such as roots. Two of these metabolites, sucrose and auxin, promote growth in root systems, but the explicit connection between photosynthetic activity and control of root architecture has not been explored. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the Arabidopsis thaliana CYCLOPHILIN 38 (CYP38) gene, which causes accumulation of pre-emergent stage lateral roots. CYP38 was previously reported to stabilize photosystem II (PSII) in chloroplasts. CYP38 expression is enriched in shoots, and grafting experiments show that the gene acts non-cell-autonomously to promote lateral root emergence. Growth of wild-type plants under low-light conditions phenocopies the cyp38 lateral root emergence defect, as does the inhibition of PSII-dependent electron transport or Nicotinamide adenine dinucleotide phosphate (NADPH) production. Importantly, these perturbations to photosynthetic activity rapidly suppress lateral root emergence, which is separate from their effects on shoot size. Supplementary exogenous sucrose largely rescued primary root (PR) growth in cyp38, but not lateral root growth. Auxin (indole-3-acetic acid (IAA)) biosynthesis from tryptophan is dependent on reductant generated during photosynthesis. Consistently, we found that wild-type seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. IAA treatment rescued the cyp38 lateral root defect, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. These data directly confirm the importance of CYP38-dependent photosynthetic activity in supporting root growth, and define the specific contributions of two metabolites in refining root architecture under light-limited conditions

As a new member of saturable absorber (SA), molybdenum carbide (Mo2C) has some excellent optical properties. Herein, we report a new type of Mo2C/fluorine mica (FM) SA device. Uniform and compact Mo2C films were deposited on the FM by magnetron sputtering method. In order to increase the laser damage threshold, an additional protective layer of silicon oxide was deposited on the Mo2C. The FM is a single-layer structure of 20 μm, and its high elasticity makes it not easy to fracture. The transmission rate of FM is as high as 90% at near infrared wavelength. FM has better heat dissipation and softening temperature than organic composite materials, so it can withstand higher laser power without being damaged. In this work, Mo2C/FM SA was cut into small pieces and inserted into erbium-doped fiber laser to achieve mode-locked operation. The pulse duration and average output power of the laser pulses were 313 fs and 64.74 mW, respectively. In addition, a 12th-order sub-picosecond harmonic mode-locking was generated. The maximum repetition rate was 321.6 MHz and the shortest pulse duration was 338 fs. The experimental results show that Mo2C/FM SA is a broadband nonlinear optical mode-locker with excellent performance.

We experimentally report on the interference phenomenon between ultrashort pulses in fiber media. When the pulse interval goes further to a certain small scale, the interference effects can arise. As a result, the spectrum appears to be a modulation phenomenon. Different from the phenomenon of bound-state pulses in a fiber laser cavity, the relationship between the modulation period of the spectrum and the pulse interval in the time domain seems to go against the interference principle. At the same time, the time interval between the two pulses is far greater than the time difference caused by the optical path difference. We are very confused. It seems that when two pulses overlap by a certain proportion in time, they will push each other apart to increase the time interval. Moreover, when the pulse interval becomes smaller and the two pulses are overlapped in time, the corresponding autocorrelation trace exhibits only one peak with regular modulation instead of the conventional three peaks with equal spacing, which looks very strange and is hard to explain. Limited by our technical tools, we could not illustrate the physical causes, but there is no doubt that it will be very meaningful to research what happens. Our observations have found some novel optical phenomena in experiment, which may provide some reference for further exploration of interference phenomena between ultrashort pulses.

The use of marginal lands in agriculture is increasingly necessary to support the global human population. Elevated salinity frequently occurs in degraded soils and hinders their use due to the negative impact salt stress has on plant growth. While the hormonal networks controlling growth have been extensively characterized in stress-sensitive plants, it is unclear how these pathways are rewired in plants that maintain growth in extreme environments. We have compared the physiological and molecular responses of four closely related members of the Brassicaceae family including two salt-tolerant species (Shrenkiella parvula and Eutrema salsugineum) and two salt-sensitive species (Sisymbrium irio and Arabidopsis thaliana) to the salt stress-induced hormone, abscisic acid (ABA). While ABA inhibits root growth in most species, we uncovered substantial growth-promoting effects in Shrenkiella parvula, due to an enhancement in cell elongation. Comparative transcriptomics informed by phylogenetic relationships uncovered lineage and extremophile-specific differences in ABA response. DNA Affinity Purification followed by sequencing (DAP-Seq) was utilized to establish gene regulatory networks (GRNs) in each species for the entire ABA-RESPONSIVE ELEMENT BINDING FACTORS (AREB/ABF) clade. Comparative GRN analysis identified relative conservation in the core ABA signaling GRN, while the auxin growth-hormone GRN was highly divergent, revealing how patterns of gain and loss of cis-regulatory elements mediate novel physiological outcomes. Our findings demonstrate that the targets of hormone signaling pathways are highly divergent between species and that diametric inversion of growth regulation is possible, even between closely related species of the same plant family.

The water stress-associated hormone abscisic acid (ABA) acts through a well-defined signal transduction cascade to mediate downstream transcriptional events important for acclimation to stress. Although ABA signaling is known to function in specific tissues to regulate root growth, little is understood regarding the spatial pattern of ABA-mediated transcriptional regulation. Here, we describe the construction and evaluation of an ABSCISIC ACID RESPONSIVE ELEMENT (ABRE)-based synthetic promoter reporter that reveals the transcriptional response of tissues to different levels of exogenous ABA and stresses. Genome-scale yeast one-hybrid screens complemented these approaches and revealed how promoter sequence and architecture affect the recruitment of diverse transcription factors (TFs) to the ABRE. Our analysis also revealed ABA-independent activity of the ABRE-reporter under nonstress conditions, with expression being enriched at the quiescent center and stem cell niche. We show that the WUSCHEL RELATED HOMEOBOX5 and NAC DOMAIN PROTEIN13 TFs regulate QC/SCN expression of the ABRE reporter, which highlights the convergence of developmental and DNA-damage signaling pathways onto this cis-element in the absence of water stress. This work establishes a tool to study the spatial pattern of ABA-mediated transcriptional regulation and a repertoire of TF-ABRE interactions that contribute to the developmental and environmental control of gene expression in roots.

Photosynthesis in leaves generates the fixed-carbon resources and essential metabolites that support sink tissues, such as roots [1]. One of these products, sucrose, is known to promote primary root growth, but it is not clear what other molecules may be involved and whether other stages of root system development are affected by photosynthate levels [2]. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the CYCLOPHILIN 38 (CYP38) gene, which causes an accumulation of pre-emergent stage lateral roots, with a minor effect on primary root growth. CYP38 was previously reported to maintain the stability of Photosystem II (PSII) in chloroplasts [3]. CYP38 expression is enriched in the shoot and grafting experiments show that the gene acts non-cell autonomously to promote lateral root emergence. Growth of wild-type plants under low light conditions phenocopied the cyp38 lateral root emergence phenotype as did the inhibition of PSII-dependent electron transport or NADPH production. Importantly, the cyp38 root phenotype is not rescued by exogenous sucrose, suggesting the involvement of another metabolite. Auxin (IAA) is an essential hormone promoting root growth and its biosynthesis from tryptophan is dependent on reductant generated during photosynthesis [4,5]. Both WT seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. The cyp38 lateral root defect is rescued by IAA treatment, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. Metabolomic profiling shows that the accumulation of several defense-related metabolites are also photosynthesis-dependent, suggesting that the regulation of a number of energy-intensive pathways are down-regulated when light becomes limiting.

Photosynthesis in leaves generates the fixed-carbon resources and essential metabolites that support sink tissues, such as roots. One of these products, sucrose, is known to promote primary root growth, but it is not clear what other molecules may be involved and whether other stages of root system development are affected by photosynthate levels. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the CYCLOPHILIN 38 (CYP38) gene, which causes an accumulation of pre-emergent stage lateral roots, with a minor effect on primary root growth. CYP38 was previously reported to maintain the stability of Photosystem II (PSII) in chloroplasts. CYP38 expression is enriched in the shoot and grafting experiments show that the gene acts non-cell autonomously to promote lateral root emergence. Growth of wild-type plants under low light conditions phenocopied the cyp38 lateral root emergence phenotype as did the inhibition of PSII-dependent electron transport or NADPH production. Importantly, the cyp38 root phenotype is not rescued by exogenous sucrose, suggesting the involvement of another metabolite. Auxin (IAA) is an essential hormone promoting root growth and its biosynthesis from tryptophan is dependent on reductant generated during photosynthesis. Both WT seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. The cyp38 lateral root defect is rescued by IAA treatment, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. Metabolomic profiling shows that the accumulation of several defense-related metabolites are also photosynthesis-dependent, suggesting that the regulation of a number of energy-intensive pathways are down-regulated when light becomes limiting.

The adaptive step-size methods including conservation quantity error method (CQEM) and local error method (LEM) are described and used to investigate the femtosecond pulse evolution in liquid-core photonic crystal fibers. The efficiency and accuracy of the numerical results obtained from CQEM and LEM in frequency domain (FD) and time domain (TD) are compared and discussed under the fixed numerical parameters respectively. The numerical results represent that LEM has the higher accuracy due to the integration of nonlinear operator that is more efficient than CQEM. The femtosecond pulse evolution in liquid-core photonic crystal fiber is described and analyzed using LEM. Moreover, the influences of the peak power of pulse and length of liquid-core photonic crystal fibers on the supercontinuum generation are also obtained based on LEM-FD. This study is helpful optimizing the numerical process in ultra-short pulse evolution based on adaptive step-size methods.

This paper briefly introduces the development status of multi-sensor data fusion technology and knowledge of the basic principles of multi-sensor data fusion technology, and highlights based on BP Fuzzy Neural Network Information Fusion Method, and will change the method to the wheelbarrow obstacle avoidance system, set up given the physical model of the whole system for a wheelbarrow and wheelbarrow sensor information fusion systems. Debug and simulate in Matlab.

In this work, we report a passively q-switched nd:yag laser at 1064 nm by using ws2 solution as the saturable absorber (sa). the ws2 solution with different concentrations (0.25, 0.5, and 1 mg/ml) were fabricated by the liquid-phase-exfoliated method and injected into quartz cells. such liquid absorbers have the virtues of adjustable optical absorption, high heat dissipation and non-contact damage. by inserting those ws2 solutions in the laser cavity, stable q-switched laser operations were obtained. the corresponding pulse duration as short as 922 ns was obtained. the result shows that the ws2 material can be act as absorber for solid-state lasers. (c) 2016 elsevier b.v. all rights reserved.

We design the high confinement InP/In 1−x Ga x As y P 1−y semiconductor waveguides and investigate the effective wavelength conversion based on this platform. Efficient confinement and mode field area fluctuation at different wavelength is analyzed to achieve the high nonlinear coefficient. The numerical results show that nearly zero phase-mismatch condition can be satisfied through dispersion tailoring of InP/In 1−x Ga x As y P 1−y waveguides, and the wavelength conversion ranging over 40 nm with the maximum conversion efficiency −26.3 dB is achieved. Meanwhile, the influences of the doping parameter y and pumping wavelength on the bandwidth and conversion efficiency are also discussed and optimized. Our demonstration of the excellent all-optical wavelength conversion properties of the InP/In 1−x Ga x As y P 1−y waveguides could pave the way towards direct integration telecom band devices on stand semiconductor platforms.

A self-assembly ruthenium material connected by Al 3 + ions ( Ru-Al ) was synthesized and used to catalyze water oxidation. This Ru-Al material displayed much better performance than its precursor and the free precursor mixed with Al 3 + ion on both efficiency and stability during the catalytic water oxidation period. Based on the catalytic metal center, a turnover number (TON) of more than 2100 was achieved.

The water stress-associated hormone abscisic acid (ABA) acts through a well-defined signal transduction cascade to mediate downstream transcriptional events important for acclimation to stress. Although ABA signaling is known to function in specific tissues to regulate root growth, little is understood regarding the spatial pattern of ABA-mediated transcriptional regulation. Here, we describe the construction and evaluation of an ABSCISIC ACID RESPONSIVE ELEMENT (ABRE)-based synthetic promoter reporter that reveals the transcriptional response of tissues to different levels of exogenous ABA and stresses. Genome-scale yeast one-hybrid screens complemented these approaches and revealed how promoter sequence and architecture affect the recruitment of diverse transcription factors (TFs) to the ABRE. Our analysis also revealed ABA-independent activity of the ABRE-reporter under nonstress conditions, with expression being enriched at the quiescent center and stem cell niche. We show that the WUSCHEL RELATED HOMEOBOX5 and NAC DOMAIN PROTEIN13 TFs regulate QC/SCN expression of the ABRE reporter, which highlights the convergence of developmental and DNA-damage signaling pathways onto this cis-element in the absence of water stress. This work establishes a tool to study the spatial pattern of ABA-mediated transcriptional regulation and a repertoire of TF-ABRE interactions that contribute to the developmental and environmental control of gene expression in roots.

The root endodermis is characterized by the Casparian strip and by the suberin lamellae, two hydrophobic barriers that restrict the free diffusion of molecules between the inner cell layers of the root and the outer environment. The presence of these barriers and the position of the endodermis between the inner and outer parts of the root require that communication between these two domains acts through the endodermis. Recent work on hormone signaling, propagation of calcium waves, and plant-fungal symbiosis has provided evidence in support of the hypothesis that the endodermis acts as a signaling center. The endodermis is also a unique mechanical barrier to organogenesis, which must be overcome through chemical and mechanical cross talk between cell layers to allow for development of new lateral organs while maintaining its barrier functions. In this review, we discuss recent findings regarding these two important aspects of the endodermis.

[EN] The architecture of the branched root system of plants is a major determinant of vigor. Water availability is known to impact root physiology and growth; however, the spatial scale at which this stimulus influences root architecture is poorly understood. Here we reveal that differences in the availability of water across the circumferential axis of the root create spatial cues that determine the position of lateral root branches. We show that roots of several plant species can distinguish between a wet surface and air environments and that this also impacts the patterning of root hairs, anthocyanins, and aerenchyma in a phenomenon we describe as hydropatterning. This environmental response is distinct from a touch response and requires available water to induce lateral roots along a contacted surface. X-ray microscale computed tomography and 3D reconstruction of soil-grown root systems demonstrate that such responses also occur under physiologically relevant conditions. Using early-stage lateral root markers, we show that hydropatterning acts before the initiation stage and likely determines the circumferential position at which lateral root founder cells are specified. Hydro-patterning is independent of endogenous abscisic acid signaling, distinguishing it from a classic water-stress response. Higher water availability induces the biosynthesis and transport of the lateral root-inductive signal auxin through local regulation of TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 and PIN-FORMED 3, both of which are necessary for normal hydropatterning. Our work suggests that water availability is sensed and interpreted at the suborgan level and locally patterns a wide variety of developmental processes in the root., We thank Jose Alonso, Fred Berger, Eva Benkova, Matt Evans, Annemarie Meijer, Ben Scheres, and Jian Xu for providing materials, and the J.R.D. laboratory for comments on the manuscript. Funding was provided by a Carnegie Institution for Science endowment, the National Research Foundation of Singapore, a National Science Foundation Graduate Research Fellowship under Grant DGE-1147470 (to N.E.R.), European Research Council FUTUREROOTS (C.J.S., M.C.T., S.J.M., and M.J.B.), and Biotechnology and Biological Sciences Research Council (C.J.S., S.J.M., and M.J.B.).

We numerically investigate the effects of pump power and high-order dispersion (HOD) on the generation and evolution of silicon-on-insulator (SOI) micro-ring resonator-based optical frequency combs (OFCs). The observed bandwidth and number of comb modes increase as the pump power enhances, which demonstrates the pump power as low as 0 dBm is required to initiate in the dual-pumped scheme, while the optimized pump power distribution ratio is around 0.5. The HOD can also be introduced to analyze the nonlinear symmetry breaking of the OFC, especially the sign and amplitude of the third-order dispersion determines the variation of the output OFC. Through optimizing the parameters, broadband OFC spanning nearly from 1200 nm to 2100 nm can be realized. This work could give insight for exploring detail characteristics of SOI micro-ring OFCs influenced by pump power and HOD, as well as provide a viable route to delicate control of OFC generation through dispersion adjusting.

Utilizing solar energy to produce hydrogen from water is a great concept to resolve the energy crisis in future, and building up highly efficient photoelectrochemical cells is considered the important way to achieve this process. While in this process, the key challenge is to realize the light driven water oxidation smoothly. The developments of water oxidation molecular devices in recent years are summarized, the assembly and properties of these molecular devices are introduced in this paper, and some opinions are put forward according to these studies.

Three new supramolecular assemblies SA1-SA3 with different linkages between the photosensitizer and catalyst have been synthesized for light driven water oxidation. With flexible -CH(2)-CH(2)- chains as the linkage, the assembly SA3 displays the best performance for photocatalytic water oxidation compared with the other two assemblies, a turnover number of 34 has been obtained based on the molecular assembly SA3 in a homogeneous system. This type of assembly connected with flexible linkages represents suitable candidates to construct photoanodes for light driven water splitting in dye sensitized photoelectrochemical devices.

Plant environmental responses involve dynamic changes in growth and signaling, yet little is understood as to how progress through these events is regulated. Here, we explored the phenotypic and transcriptional events involved in the acclimation of the Arabidopsis thaliana seedling root to a rapid change in salinity. Using live-imaging analysis, we show that growth is dynamically regulated with a period of quiescence followed by recovery then homeostasis. Through the use of a new high-resolution spatio-temporal transcriptional map, we identify the key hormone signaling pathways that regulate specific transcriptional programs, predict their spatial domain of action, and link the activity of these pathways to the regulation of specific phases of growth. We use tissue-specific approaches to suppress the abscisic acid (ABA) signaling pathway and demonstrate that ABA likely acts in select tissue layers to regulate spatially localized transcriptional programs and promote growth recovery. Finally, we show that salt also regulates many tissue-specific and time point-specific transcriptional responses that are expected to modify water transport, Casparian strip formation, and protein translation. Together, our data reveal a sophisticated assortment of regulatory programs acting together to coordinate spatially patterned biological changes involved in the immediate and long-term response to a stressful shift in environment.

Natural rubber latex, one of the most important biosynthesized polymers, was successfully used as template in the syntheses of cobalt doped mesoporous alumina. The synthesized cobalt doped mesoporous alumina was characterized by a combination of various physicochemical techniques; N2 adsorption/desorption, diffuse reflectance UV–vis, X-ray diffraction and FT-IR. It was used as an efficient catalyst for the oxidation of tetralin to 1-tetralone under mild conditions for the first time. The catalyst exhibited high substrate conversion (80.3%) and good product (1-tetralone) selectivity (74.5%). Fast hot catalyst filtration experiments proved that the catalyst acted as a heterogeneous one; it can be reused three times without losing its activity. By contrast, undoped alumina synthesized using rubber latex as template, cobalt-doped alumina synthesized by a using traditional chemical template: poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (P123) as template, and cobalt-doped mesoporous silica synthesized by using natural rubber latex as template exhibited much lower activities.

We demonstrate an all polarization-maintaining (PM) fiber-based optical frequency comb and provide the detailed environmental stability analysis results. The frequency comb has been built by commercial available PM fiber completely, and its static uncertainty in optical domain is 350 Hz in 1 s when referenced to a low noise oven controlled crystal oscillator. The acoustic resonant frequencies of the system have been measured. It is proved that acoustic-vibration induced phase noise could be eliminated by low pass vibration-isolation structure. Further, the existence of the optimum working temperature is illustrated. At this temperature (289.6 K), the out-loop integrated phase noise of f(r) and the temperature-drift induced instability of f(CEO) reach the lowest level 31.6 μrad and 0 kHz/(mW∙K) respectively. Finally, the system is proved to be stable under different humidity (18% ~80%) by a 240-day-long record of the f(CEO).

We had proved that a kind of graphene nanomaterial “carboxyl-functionalized graphene oxide (GO-COOH)” possessed nonlinear saturable absorber (SA) property. The modulation depth of a GO-COOH water solution was measured as ∼8%. Moreover, a GO-COOH-based SA device was made and applied in an erbium-doped fiber laser. In this fiber laser, Q-switching pulses and mode-locked pulses were both obtained. With an increase in the pump power, the pulse width of Q-switching pulses decreased from 9.05 to 2.49 μs. The mode-locked pulse width was 844 fs, and the corresponding spectral bandwidth was 3.64 nm. Moreover, polarization adjusting or control was not needed during the whole process of mode locking. It illustrated that the proposed fiber laser incorporating GO-COOH could endure bigger intracavity birefringence. Our results indicated that the GO-COOH nanomaterial was a promising SA for generating high-performance pulse lasers.

We experimentally report on the generation of single and multiple dissipative soliton via nonlinear polarization rotation technique. The spectrum of the mode-locked dissipative soliton exhibits typical steep edges with a flat top; the pulse duration is 10.07 ps. It is found that with the pump power increasing from 110 mW to 161 mW, the top of the mode-locked spectrum becomes flater and the 3-dB spectral bandwidth is broadened, which indicates that the gain-dispersion effect is lowered under stronger pump. However, the full bandwidth of the spectrum is narrowed, which proves that the spectral filter effect increases and overcomes the effect of self-phase modulation induced spectral broadening. Such a phenomenon was not noticed nor reported before. Our experiment also demonstrates that the pulse interval is highly dependent on the input pump power: with pump power increasing, the pulse interval tends towards more uniform. So our observation qualitatively analyzes the relationship between mode-locked pulse characteristics and input pump power.

In order to acclimate to the soil environment, plants need to constantly optimize their root system architecture for efficient resource uptake. Roots are highly sensitive to changes in their surrounding environment and root system responses to a stress such as salinity and drought can be very dynamic and complex in nature. These responses can be manifested differentially at the cellular, tissue, or organ level and between the types of roots in a root system. Therefore, various approaches must be taken to quantify and characterize these responses. In this chapter, we review methods to study basic root growth traits, such as root length, cell cycle activity and meristem size, cell shape and size that form the basis for the emergent properties of the root system. Methods for the detailed analysis of lateral root initiation and postemergence growth are described. Finally, several live-imaging systems, which allow for dynamic imaging of the root, will be explored. Together these tools provide insight into the regulatory steps that sculpt the root system upon environmental change and can be used as the basis for the evaluation of genetic variation affecting these pathways.

We have experimentally observed conventional solitons and rectangular pulses in an erbium-doped fiber laser operating at anomalous dispersion regime. The rectangular pulses exhibit broad quasi-Gaussian spectra (~40 nm) and triangular autocorrelation traces. With the enhancement of pump power, the duration and energy of the output rectangular pulses almost increase linearly up to 330 ps and 3.2 nJ, respectively. It is demonstrated that high-energy pulses can be realized in anomalous-dispersion regime, and may be explained as dissipative soliton resonance. Our results have confirmed that the formation of dissipative soliton resonance is not sensitive to the sign of cavity dispersion.

We experimentally demonstrate unequal pulses delivered from an erbium-doped fiber (EDF) laser with net-normal dispersion. Two types of pulses with different durations, energies, and spectra coexist in the same ring cavity. The output spectrum exhibits a broadband base that corresponds to the main pulse and a small rectangular lump that corresponds to the additional satellite pulse. With the enhancement of pump power, the intensity of main pulse almost keeps unchanged while the satellite pulse nearly increases linearly. Based on experimental results, it is indicated that two different pulse shaping mechanisms coexist in laser cavity, where the nonlinear polarization rotation (NPR) and spectral filtering (SF) effect contribute to the formation of main pulse and satellite pulse, respectively.

Four different types of pulses are experimentally obtained in one erbium-doped all-fiber laser with large net-normal dispersion. The proposed laser can deliver the rectangular-spectrum (RS), Gaussian-spectrum (GS), broadband-spectrum (BS), and noise-like pulses by appropriately adjusting the polarization states. These kinds of pulses have distinctly different characteristics. The RS pulses can easily be compressed to femtosecond level whereas the pulse energy is restricted by the trend of multi-pulse shaping with excessive pump. The GS and BS pulses always maintain the single-pulse operation with much higher pulse-energy and accumulate much more chirp. After launching the pulses into the photonic-crystal fiber, the supercontinuum can be generated with the bandwidth of >700 nm by the BS pulses and of ~400 nm by the GS pulses, whereas it can hardly be generated by the RS pulses. The physical mechanisms behind the continuum generation are qualitatively investigated relating to different operating regimes. This work could help to a deeper insight of the normal-dispersion pulses.

Intelligent traffic technology aims at promoting traffic management and providing information services to public. The existing traffic information systems, developed with their traffic subsystem background and characterized by management-oriented applications, are incapable of meeting the dynamic requests of different customers for comprehensive and personal information services, and further go against the optimal utilization of resources. This paper analyzes the diverse traffic information needs of the public, the requirements for the on-demand integration of traffic information applications and various integration solutions, and the challenges that they pose. The analysis concludes that an approach combining the semantic grid and SOA technologies would be an appropriate solution. Therefore, a generic conceptual architecture for the integration using the Semantic SOA approach is proposed. The traffic system is redesigned as a service system, with the services being identified and managed with a UDDI server. Most services come from existing applications and are encapsulated within SOAP. The framework that implements the dynamic service flow composition is designed for customer-oriented services. A scenario is presented to show a potential application of this architecture, which analyzes the business model's value of this SOA solution.

This study presents a passively q-switched nd:yag laser using a mos2 solution as a saturable absorber. the prepared mos2 solution saturable absorber features adjustable optical absorption, high heat dissipation, and non-contact damage. by inserting the mos2 solution saturable absorber into a z-type nd:yag laser cavity, a stable q-switched laser with the maximum repetition rate of 20.8 khz centered at 1064.24 nm was achieved, with the shortest pulse width at 2.8 mu s. the results experimentally confirm the potential application of a mos2 solution saturable absorber for high performance q-switched solid-state lasers.

The report firstly propose a new WS(2) absorber based on fluorine mica (FM) substrate. The WS(2) material was fabricated by thermal decomposition method. The FM was stripped into one single layer as thin as 20 μm and deposited WS(2) on it, which can be attached to the fiber flank without causing the laser deviation. Similar to quartz, the transmission rate of FM is as high as 90% at near infrared wavelength from one to two micrometers. Furthermore, FM is a highly elastic material so that it is not easy to break off even its thickness was only 20 μm. On the contrary, quartz is hard to be processed and easy to break off when its thickness is less than 100 μm. Compared to organic matrix such as polyvinyl alcohol (PVA), FM has higher softening temperature, heat dissipation and laser damage threshold than those of organic composites. In our work, the modulation depth (MD) and non-saturable losses (NLs) of this kind of saturable absorber were measured to be 5.8% and 14.8%, respectively. The WS(2)/FM absorber has a high damage threshold of 406 MW/cm(2), two times higher than that of WS(2)/PVA. By incorporating the saturable absorber into Yb-doped fiber laser cavity, a mode-locked fiber laser was achieved with central wavelength of 1052.45 nm. The repetition rate was 23.26 MHz and the maximum average output power was 30 mW. The long term stability of working was proved to be good too. The results indicate that WS(2)/FM film is a practical nonlinear optical material for photonic applications.

The report proposed a saturable absorber based on a D-shaped fiber embedded in a single-walled carbon nanotube solution. Such a saturable absorber solution method with a D-shaped fiber has the virtues of good antioxidant capacity, excellent scattering resistance, high heat dissipation, and high damage threshold. The nonsaturable loss of this kind of saturable absorber was evaluated to be 3%. To the best of our knowledge, this is the lowest value compared with other carbon nanotube saturable absorbers. By incorporating the saturable absorber into a Yb-doped fiber laser cavity, a mode-locked fiber laser was achieved with a central wavelength of 1054.16 nm. The repetition rate was 23 MHz with a signal-to-noise ratio of 60 dB, and the pulse duration was measured to be 194 ps. The long-term working stability of working is also good. The results indicated that the solution method with a D-shaped fiber possesses a potential for fiber laser stability applications. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)

An all-normal dispersion passively mode-locked Yb-doped fiber laser with a Bi2Te3 absorber is presented. The modulation depth of this kind of saturable absorber was measured to be 8.4%. By incorporating a Bi2Te3/PVA film into a Yb-doped fiber laser oscillator, a mode-locked fiber laser oscillator was achieved. The repetition rate and the central wavelength are 25.6 MHz and 1052.7 nm, respectively. The 3-dB spectral width is 0.45 nm and the pulse duration is 417 ps. The results indicate that topological insulator Bi2Te3 possesses the potential for ultrafast fiber laser application. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)