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Plasmonic metal nanostructures (PMNs) are characterized by the plasmon oscillation of conduction band electron in response to external radiation, enabling strong light absorption and scattering capacities and near-field amplification. Owing to these enhanced light-matter interactions, PMNs have garnered extensive research interest in the past decades. Notably, a growingly large number of reports show that the energetics and kinetics of chemical transformations on PMNs can be modified upon photoexcitation of their plasmons, giving rise to a new paradigm of manipulating the reaction rate and selectivity of chemical reactions. On the other hand, there is urgent need to achieve clear understanding of the mechanism underlying the photo-mediated chemical transformations on PMNs for unleashing their full potential in converting solar energy to chemicals. In this perspective, we review current fundamental concepts of photo-mediated chemical transformations executed at PMNs. Three pivotal mechanistic questions, i.e., thermal and nonthermal effects, direct and indirect charge transfer processes, and the specific impacts of plasmon-induced potentials, are explored based on recent studies. We highlight the critical aspects in which major advancements should be made to facilitate the rational design and optimization of photo-mediated chemical transformations on PMNs in the future., (© 2021 The Author(s).)

We present a reference-free method to determine electrical parameters of thin conducting films by steady state transmission-mode terahertz time-domain spectroscopy (THz-TDS). We demonstrate that the frequency-dependent AC conductivity of graphene can be acquired by comparing the directly transmitted THz pulse with a transient internal reflection within the substrate which avoids the need for a standard reference scan. The DC sheet conductivity, scattering time, carrier density, mobility, and Fermi velocity of graphene are retrieved subsequently by fitting the AC conductivity with the Drude model. This reference-free method was investigated with two complementary THz setups: one commercial fibre-coupled THz spectrometer with fast scanning rate (0.2-1.5 THz) and one air-plasma based ultra-broadband THz spectrometer for greatly extended frequency range (2-10 THz). Certain propagation correction terms for more accurate retrieval of electrical parameters are discussed.

Background: Mutations in the fused in sarcoma (FUS) gene have been associated with amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration, and essential tremor. Among the FUS mutations, p.P525L as a hot spot variant has been reported in more than 20 patients with ALS. Apart from the typical ALS phenotype, patients with p.P525L mutation exhibit some atypical symptoms. However, movement disorders related to p.P525L mutation have not been emphasized currently., Methods: Two unrelated patients with ALS were evaluated through a set of clinical and laboratory tests. The genetic screening was performed through next-generation sequencing. Muscle biopsies were performed on the 2 patients. Muscle samples were stained according to standard histological and immunohistochemical procedures., Results: The first patient presented with juvenile-onset neurogenic weakness and wasting and simultaneously had dropped head, ophthalmoplegia, tremor, involuntary movements, and cognitive impairments. The second patient showed a typical ALS phenotype and prominent adventitious movements. Genetic screening disclosed de novo p.P525L FUS mutation in the 2 patients by family cosegregation analysis. Muscle biopsy showed neurogenic patterns and numerous lipid droplets aggregating in the fibers., Conclusion: Apart from the typical ALS phenotype, patients with p.P525L mutation in the FUS gene can present with great clinical heterogeneity including multiple movement disorders. Numerous lipid droplets in muscle fibers indicate that skeletal muscle is likely an important therapeutic target for ALS., (© 2020 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)

During plant-pathogen interactions, pathogens secrete many rapidly evolving, small secreted proteins (SSPs) that can modify plant defense and permit pathogens to colonize plant tissue. The fungal pathogen Zymoseptoria tritici is the causal agent of Septoria tritici blotch (STB), one of the most important foliar diseases of wheat, globally. Z. tritici is a strictly apoplastic pathogen that can secrete numerous proteins into the apoplast of wheat leaves to promote infection. We sought to determine if, during STB infection, wheat also secretes small proteins into the apoplast to mediate the recognition of pathogen proteins and/or induce defense responses. To explore this, we developed an SSP-discovery pipeline to identify small, secreted proteins from wheat genomic data. Using this pipeline, we identified 6,998 SSPs, representing 2.3% of all proteins encoded by the wheat genome. We then mined a microarray dataset, detailing a resistant and susceptible host response to STB, and identified 141 Z. tritici - responsive SSPs, representing 4.7% of all proteins encoded by Z. tritici - responsive genes. We demonstrate that a subset of these SSPs have a functional signal peptide and can interact with Z. tritici SSPs. Transiently silencing two of these wheat SSPs using virus-induced gene silencing (VIGS) shows an increase in susceptibility to STB, confirming their role in defense against Z. tritici ., (Copyright © 2020 Zhou, Benbow, Brennan, Arunachalam, Karki, Mullins, Feechan, Burke and Doohan.)

Understanding the nuances of host/pathogen interactions are paramount if we wish to effectively control cereal diseases. In the case of the wheat/ Zymoseptoria tritici interaction that leads to Septoria tritici blotch (STB) disease, a 10,000-year-old conflict has led to considerable armaments being developed on both sides which are not reflected in conventional model systems. Taxonomically restricted genes (TRGs) have evolved in wheat to better allow it to cope with stress caused by fungal pathogens, and Z. tritici has evolved specialized effectors which allow it to manipulate its' host. A microarray focused on the latent phase response of a resistant wheat cultivar (cv. Stigg) and susceptible wheat cultivar (cv. Gallant) to Z. tritici infection was mined for TRGs within the Poaceae. From this analysis, we identified two TRGs that were significantly upregulated in response to Z. tritici infection, Septoria-responsive TRG6 and 7 (TaSRTRG6 and TaSRTRG7) . Virus induced silencing of these genes resulted in an increased susceptibility to STB disease in cvs. Gallant and Stigg, and significantly so in the latter (2.5-fold increase in STB disease). In silico and localization studies categorized TaSRTRG6 as a secreted protein and TaSRTRG7 as an intracellular protein. Yeast two-hybrid analysis and biofluorescent complementation studies demonstrated that both TaSRTRG6 and TaSRTRG7 can interact with small proteins secreted by Z. tritici (potential effector candidates). Thus we conclude that TRGs are an important part of the wheat- Z. tritici co-evolution story and potential candidates for modulating STB resistance., (Copyright © 2020 Brennan, Zhou, Benbow, Ajaz, Karki, Hehir, O’Driscoll, Feechan, Mullins and Doohan.)

Hot carriers (HCs) and thermal effects, stemming from plasmon decays, are crucial for most plasmonic applications. However, quantifying these two effects remains extremely challenging due to the experimental difficulty in accurately measuring the temperature at reaction sites. Herein, we provide a novel strategy to disentangle HCs from photothermal effects based on the different traits of heat dissipation (long range) and HCs transport (short range), and quantitatively uncover the dominant and potential-dependent role of photothermal effect by investigating the rapid- and slow-response currents in plasmon-mediated electrochemistry at nanostructured Ag electrode. Furthermore, the plasmoelectric surface potential is found to contribute to the rapid-response currents, which is absent in the previous studies., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We demonstrate the first megahertz (MHz) repetition-rate, broadband terahertz (THz) source based on optical rectification in the organic crystal HMQ-TMS driven by a femtosecond Yb:fibre laser. Pumping at 1035 nm with 30 fs pulses, we achieve few-cycle THz emission with a smooth multi-octave spectrum that extends up to 6 THz at -30 dB, with conversion efficiencies reaching 10 -4 and an average output power of up to 0.38 mW. We assess the thermal damage limit of the crystal and conclude a maximum fluence of ∼1.8 mJ·cm -2 at 10 MHz with a 1/e 2 pump beam diameter of 0.10 mm. We compare the performance of HMQ-TMS with the prototypical inorganic crystal gallium phosphide (GaP), yielding a tenfold electric field increase with a peak on-axis field strength of 7 kV·cm -1 and almost double the THz bandwidth. Our results further demonstrate the suitability of organic crystals in combination with fibre lasers for repetition-rate scaling of broadband, high-power THz sources for time-domain spectroscopic applications.

Neoantigens play important roles in cancer immunotherapy. Current methods used for neoantigen prediction focus on the binding between human leukocyte antigens (HLAs) and peptides, which is insufficient for high-confidence neoantigen prediction. In this study, we apply deep learning techniques to predict neoantigens considering both the possibility of HLA-peptide binding (binding model) and the potential immunogenicity (immunogenicity model) of the peptide-HLA complex (pHLA). The binding model achieves comparable performance with other well-acknowledged tools on the latest Immune Epitope Database (IEDB) benchmark datasets and an independent mass spectrometry (MS) dataset. The immunogenicity model could significantly improve the prediction precision of neoantigens. The further application of our method to the mutations with pre-existing T-cell responses indicating its feasibility in clinical application. DeepHLApan is freely available at https://github.com/jiujiezz/deephlapan and http://biopharm.zju.edu.cn/deephlapan., (Copyright © 2019 Wu, Wang, Zhang, Zhou, Zhao, Su, Gu, Wu, Zhou and Chen.)

A pure silica photonic crystal fiber with a group velocity dispersion (β 2 ) of 4  ps 2 /km at 1.55 μm and less than 7  ps 2 /km from 1.32 μm to the zero dispersion wavelength (ZDW) 1.80 μm was designed and fabricated. The dispersion of the fiber was measured experimentally and found to agree with the fiber design, which also provides low loss below 1.83 μm due to eight outer rings with increased hole diameters. The fiber was pumped with a 1.55 μm, 125 fs laser and, at the maximum in-coupled peak power (P 0 ) of 9 kW, a 1.34-1.82 μm low-noise spectrum with a relative intensity noise below 2.2% was measured. The numerical modeling agreed very well with the experiments and showed that P 0 could be increased to 26 kW before noise from solitons above the ZDW started to influence the spectrum by pushing high-noise dispersive waves through the spectrum.

We investigate the dielectric properties of the 4H and 6H polytypes of silicon carbide in the 0.1-19 THz range, below the fundamental transverse-optical phonons. Folding of the Brillouin zone due to the specific superlattice structure of the two polytypes leads to activation of acoustic phonon modes. We use a combination of ultrabroadband terahertz time-domain spectroscopy and simulations based on density-functional perturbation theory to observe and characterize these modes, including band splitting due to the dissimilar carbon and silicon sublattices of the structures, and an indirect measurement of the anisotropic sound velocities in the two polytypes.

Tumor-specific neoantigens have attracted much attention since they can be used as biomarkers to predict therapeutic effects of immune checkpoint blockade therapy and as potential targets for cancer immunotherapy. In this study, we developed a comprehensive tumor-specific neoantigen database (TSNAdb v1.0), based on pan-cancer immunogenomic analyses of somatic mutation data and human leukocyte antigen (HLA) allele information for 16 tumor types with 7748 tumor samples from The Cancer Genome Atlas (TCGA) and The Cancer Immunome Atlas (TCIA). We predicted binding affinities between mutant/wild-type peptides and HLA class I molecules by NetMHCpan v2.8/v4.0, and presented detailed information of 3,707,562/1,146,961 potential neoantigens generated by somatic mutations of all tumor samples. Moreover, we employed recurrent mutations in combination with highly frequent HLA alleles to predict potential shared neoantigens across tumor patients, which would facilitate the discovery of putative targets for neoantigen-based cancer immunotherapy. TSNAdb is freely available at http://biopharm.zju.edu.cn/tsnadb., (Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Surface enhanced Raman spectroscopy (SERS) is a powerful spectroscopic technique with unique vibrational fingerprints, making it an ideal candidate for in situ multiphase detection. However, it is a great challenge to determine how to guide the SERS sensor to target molecules of interest in multiphase heterogeneous samples with minimal disturbance. Here, we present a portable ultrasensitive and highly repeatable SERS sensor for in situ multiphase detection. The sensor is composed of commercial Ag acupuncture needle and PVP-Au nanoparticles (Au NPs). The PVP on the Au NPs can adsorb and induce the Au NPs into a highly uniform array on the surface of the Ag needle because of its adhesiveness and steric nature. The Au NPs-Ag Needle system (Au-AgN) holds a huge SERS effect, which is enabled by the multiple plasmonic couplings from particle-film and interparticle. The PVP, as the amphiphilic polymer, promotes the target molecules to adsorb on surface of the Au-AgN whether in the oil phase or in the water phase. In this work, the Au-AgN sensor was directly inserted into the multiphase system with the laser in situ detection, and SERS detection at different spots of the Au-AgN sensor provided Raman signal of targets molecule in the different phase. In situ multiphase detection can minimize the disturbance of sampling and provide more accurate information. The facile fabrication and amphiphilic functionalization make Au-AgN sensor as generalized SERS detection platform for on-site testing of aqueous samples, organic samples, even the multiphase heterogeneous samples.

Liquid interfacial self-assembly of metal nanoparticles holds great promise for its various applications, such as in tunable optical devices, plasmonics, sensors, and catalysis. However, the construction of large-area, ordered, anisotropic, nanoparticle monolayers and the acquisition of self-assembled interface films are still significant challenges. Herein, a rapid, validated method to fabricate large-scale, close-packed nanomaterials at the cyclohexane/water interface, in which hydrophilic cetyltrimethylammonium bromide coated nanoparticles and gold nanorods (AuNRs) self-assemble into densely packed 2D arrays by regulating the surface ligand and suitable inducer, is reported. Decorating AuNRs with polyvinylpyrrolidone not only extensively decreases the charge of AuNRs, but also diminishes repulsive forces. More importantly, a general, facile, novel technique to transfer an interfacial monolayer through a designed in situ reaction cell linked to a microfluidic chip is revealed. The self-assembled nanofilm can then automatically settle on the substrate and be directly detected in the reaction cell in situ by means of a portable Raman spectrometer. Moreover, a close-packed monolayer of self-assembled AuNRs provides massive, efficient hotspots to create great surface-enhanced Raman scattering (SERS) enhancement, which provides high sensitivity and reproducibility as the SERS-active substrate. Furthermore, this strategy was exploited to detect drug molecules in human urine for cyclohexane-extracted targets acting as the oil phase to form an oil/water interface. A portable Raman spectrometer was employed to detect methamphetamine down to 100 ppb levels in human urine, exhibiting excellent practicability. As a universal platform, handy tool, and fast pretreatment method with a good capability for drug detection in biological systems, this technique shows great promise for rapid, credible, and on-spot drug detection., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Intramolecular proton transfer of hypoxanthine, induced by application of a laser on the surface of a bare noble nanomaterial, was monitored in real time using surface-enhanced Raman spectroscopy (SERS). This monitoring demonstrated the dependence of the reaction on the identity of the nanomaterial and on the laser power density. The results pave the way for monitoring the proton transfer reaction in various relevant fields. In addition, we observed the presence of the proton transfer phenomenon of hypoxanthine in serum, providing a way to avoid the effect of proton transfer and hence achieve more reliable spectra of sera for clinical diagnosis.

Surface-enhanced Raman spectroscopy (SERS) as a powerful qualitative analysis method has been widely applied in many fields. However, SERS for quantitative analysis still suffers from several challenges partially because of the absence of stable and credible analytical strategy. Here, we demonstrate that the optimal hotspots created from dynamic surfaced-enhanced Raman spectroscopy (D-SERS) can be used for quantitative SERS measurements. In situ small-angle X-ray scattering was carried out to in situ real-time monitor the formation of the optimal hotspots, where the optimal hotspots with the most efficient hotspots were generated during the monodisperse Au-sol evaporating process. Importantly, the natural evaporation of Au-sol avoids the nanoparticles instability of salt-induced, and formation of ordered three-dimensional hotspots allows SERS detection with excellent reproducibility. Considering SERS signal variability in the D-SERS process, 4-mercaptopyridine (4-mpy) acted as internal standard to validly correct and improve stability as well as reduce fluctuation of signals. The strongest SERS spectra at the optimal hotspots of D-SERS have been extracted to statistics analysis. By using the SERS signal of 4-mpy as a stable internal calibration standard, the relative SERS intensity of target molecules demonstrated a linear response versus the negative logarithm of concentrations at the point of strongest SERS signals, which illustrates the great potential for quantitative analysis. The public drugs 3,4-methylenedioxymethamphetamine and α-methyltryptamine hydrochloride obtained precise analysis with internal standard D-SERS strategy. As a consequence, one has reason to believe our approach is promising to challenge quantitative problems in conventional SERS analysis.

This article presents a general method for the detection of protein kinase with a peptide-like kinase inhibitor as the bioreceptor, and it was done by converting gold nanoparticles (AuNPs)-based colorimetric assay into sensitive electrochemical analysis. In the colorimetric assay, the kinase-specific aptameric peptide triggered the aggregation of AuNPs in solution. However, the specific binding of peptide to the target protein (kinase) inhibited its ability to trigger the assembly of AuNPs. In the electrochemical analysis, peptides immobilized on a gold electrode and presented as solution triggered together the in situ formation of AuNPs-based network architecture on the electrode surface. Nevertheless, the formation of peptide-kinase complex on the electrode surface made the peptide-triggered AuNPs assembly difficult. Electrochemical impedance spectroscopy was used to measure the change in surface property in the binding events. When a ferrocene-labeled peptide (Fc-peptide) was used in this design, the network of AuNPs/Fc-peptide produced a good voltammetric signal. The competitive assay allowed for the detection of protein kinase A with a detection limit of 20 mU/mL. This work should be valuable for designing novel optical or electronic biosensors and likely lead to many detection applications., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Target analyte detection in complex systems with high selectivity and repeatability is crucial to analytical technology and science. Here we present a two-dimensional (2D) surface-enhanced resonance Raman scattering (SERRS) platform, which takes advantages of the high selectivity of the SERRS sensor as well as the sensitivity and reproducibility of the interfacial SERS platform, for detecting trace epinephrine (EP) in the serum. To realize sensitive and selective detection of EP in a complex system, Au NPs are modified with α,β-nitriloacetic acid and Fe(NO 3 ) 3 to form the Au NP-(Fe-NTA) sensor, and as a consequence, EP can be rapidly captured by the sensor on the surface of Au NPs and then delivered at the cyclohexane/water interface. More importantly, we synthesized the extremely stable Au NPs (PVP-stabilized Au NPs), where the presence of PVP prevents aggregation of Au NPs during the self-assembly process and then makes a more uniform distribution of Au NPs with analytes at the cyclohexane/water interface, approximately 2 nm interparticle distance between the Au NPs, which has been proved by synchrotron radiation grazing incidence small-angle X-ray scattering (SR-GISAXS) experiments. The self-assembly method not only effectively avoids the aggregation of Au NPs and decreases the influence of the background signal but also can capture and enrich EP molecules in the cyclohexane/water interface, realizing the sensitive and selective detection of EP in complex serum sample. This strategy overcomes the difficulty of bringing nanostructures together to form efficient interparticle distance with simple fabrication and maximum uniformity and also provides a powerful nanosensor for tracing amounts of analyte molecules in a complex system with the advantages of capturing and enriching of target molecules in the liquid/liquid interface during the self-assembly process. Our SERRS platform opens vast possibilities for repeatability, sensitivity, and selectivity detection of targets in various complex fields.

Beta-amyloid (Aβ) peptides are the major constituents of senile plaques in the brains of Alzheimer's disease (AD) patients. Aβ monomers (AβMs) can coalesce to form small, soluble oligomers (AβOs), followed by reorganization and assembly into long, thread-like fibrils (AβFs). Recently, soluble AβOs have been regarded as reliable molecular biomarkers for the diagnosis of AD because of their high toxicity for neuronal synapse and high concentration levels in the brains of AD patients. In this work, we reported a label-free, sensitive and selective method for visual and fluorescent detection of AβOs based on the inner filter effect (IFE) of gold nanoparticles (AuNPs) on the fluorescence of CdTe quantum dots (QDs). Specifically, the fluorescence of CdTe QDs was quenched significantly by AuNPs through the IFE. PrP(95-110), an AβOs-specific binding peptide from cellular prion protein, triggered the aggregation and color change of AuNPs suspension; thus, the IFE of AuNPs on the fluorescence of CdTe QDs was weakened and the fluorescence intensity was recovered. However, in the presence of AβOs, the specific interaction of AβOs and PrP(95-110) prevented the absorption of PrP(95-110) onto the surface of AuNPs. As a result, the aggregation of AuNPs was inhibited and the fluorescence intensity of CdTe QDs was quenched again. This label-free method is specific for detection of AβOs but not for AβMs and AβFs. The detection limits were found to be 0.5nM for the visual assay and 0.2nM for the fluorescent detection. We believe that this work would be valuable for many investigations related to AD diagnosis and drug discovery., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: To observe the difference of clinical effects of acupoints selected based on meridian differen-tiation and conventional method for cervical spondylosis radiculopathy(CSR) treated with acupuncture and moxibustion., Methods: Sixty patients with CSR were randomly divided into an observation group and a control group,30 cases in each one. Ashi points of the injured meridians in the neck,namely six- he points,were selected in the observation group,matched with luo -connecting points of the injured meridians on the same side and the interiorly-exteriorly correlated meridians on the opposite side. Conventional acupuncture was used on Fengchi(GB 20),Jiaji(EX-B 2) of the neck,Tianzhu(BL 10),Jianjing(GB 21),Houxi(SI 3),Hegu(LI 4) and Waiguan(TE 5) on the affected side in the control group. Treatment was given once every other day,three times a week and total 12 times in the two groups. Twenty subscales for CSR and visual analogue scale(VAS) were observed before and after treatment,and total effects were evaluated after treatment., Results: The effective rate of the observation group was 93.3%(28/30),which was better than 66.7%(20/30) of the control group( P <0.05). The scores of 20 subscales and VAS after treatment were all improved compared with those before treatment in the two groups(all P <0.01),with more apparent change in the observation group(both P <0.05)., Conclusions: The effect of acupuncture and moxibustion based on meridian differentiation is obvious,and superior to that of conventional acupoints selection.

Key Message: Transgenic tall fescue plants expressing RNAi constructs of essential genes of Rhizoctonia solani were resistant to R. solani. Tall fescue (Festuca arundinacea Schreb.) is an important turf and forage grass species widely used for home lawns and on golf courses in North Carolina and other transition zone states in the US. The most serious and frequently occurring disease of tall fescue is brown patch, caused by a basidiomycete fungus, Rhizoctonia solani. This research demonstrates resistance to brown patch disease achieved by the application of host induced gene silencing. We transformed tall fescue with RNAi constructs of four experimentally determined "essential" genes from R. solani (including genes encoding RNA polymerase, importin beta-1 subunit, Cohesin complex subunit Psm1, and a ubiquitin E3 ligase) to suppress expression of those genes inside the fungus and thus inhibit fungal infection. Four gene constructs were tested, and 19 transgenic plants were obtained, among which 12 plants had detectable accumulation of siRNAs of the target genes. In inoculation tests, six plants displayed significantly improved resistance against R. solani. Lesion size was reduced by as much as 90 %. Plants without RNAi accumulation did not show resistance. To our knowledge, this is the first case that RNAi constructs of pathogen genes introduced into a host plant can confer resistance against a necrotrophic fungus.

To explore the anti-tumor effect and immune mechanism mediated by a new recombinant adeno-associated virus (rAAV) encoding secondary lymphoid tissue chemokine (SLC) mature peptide gene. AAV Helper-Free system was used for rAAV-SLC package. The anti-tumor effect of SLC was detected by bearing tumor established from Hepal-6 cells both in C57BL/6J and nude mice. Flow cytometry analysis and IHC for Tumor-infiltrating T cells and CD11c+DCs were also investigated to explore the immunological mechanism. rAAV-SLC was successfully packaged in AAV293 cells and transfected Hepal-6 tumor cells at high efficiency. The anti-tumor effect was demonstrated by less tumor weight and longer survival outcome. Coincident with the anti-tumor response, local elaboration of SLC within the tumor bed elicited a heavy infiltration of CD4+, CD8+T cells and CD11c+ dendritic cells into the tumor sites. More importantly, there was higher infiltration of Foxp3+ regulatory T cells (Tregs). Local elaboration of SLC mediated by rAAV-SLC has strong T cell mediated anti-tumor effect. The study also suggested that Tregs in the tumor microenvironment tampered the anti-tumor effect.

Reaction of cyclooctatetraene (COT) iron(II) tricarbonyl, [Fe(cot)(CO)(3)], with one equivalent of K(4)Ge(9) in ethylenediamine (en) yielded the cluster anion [Ge(8)Fe(CO)(3)](3-) which was crystallographically-characterized as a [K(2,2,2-crypt)](+) salt in [K(2,2,2-crypt)](3)[Ge(8)Fe(CO)(3)]. The chemically-reduced organometallic species [Fe(η(3)-C(8)H(8))(CO)(3)](-) was also isolated as a side-product from this reaction as [K(2,2,2-crypt)][Fe(η(3)-C(8)H(8))(CO)(3)]. Both species were further characterized by EPR and IR spectroscopy and electrospray mass spectrometry. The [Ge(8)Fe(CO)(3)](3-) cluster anion represents an unprecedented functionalized germanium Zintl anion in which the nine-atom precursor cluster has lost a vertex, which has been replaced by a transition-metal moiety.

We present the results of a novel numerical and experimental investigation aimed at obtaining efficient 1.05 mum operation with a Yb:YAG laser. The model shows that the emitting wavelength of the Yb:YAG laser is affected by the combination of length and doping concentration of the gain medium. Efficient continuous-wave laser operation at the wavelength of 1050 nm was experimentally obtained in good agreement with the model predictions. Based on continuous-wave operation, generation of 1.8 ps laser pulses at the central wavelength of 1050 nm, as well as 170 fs laser pulses at the central wavelength of 1053 nm, were realized.