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The first observations and classification of deuterium beam-driven sub-cyclotron frequency range Alfvén eigenmodes (AEs) are presented for the MAST-Upgrade tokamak. Sets of observed eigenmodes are separated in frequency by approximately 200 kHz. We observe a lower frequency separation of ∼10 kHz within each set, and the toroidal mode number n increases with frequency sequentially. The ∼200 kHz step between the sets coincides with the interval between successive curves of the Shear Alfvén continuum according to linear ideal MHD modeling. The sub-cyclotron frequency AEs can be identified as the global AEs (GAEs) localized at the continuum extrema regions. Each set contains the same range of n . These observations are consistent with our GAE modeling. In low plasma current ( I _p ) discharges, we observe only GAEs propagating counter to the plasma current and the beam direction. These GAEs are located near the magnetic axis. We observe counter and co-propagating GAEs simultaneously in higher I _p discharges. The co-propagating GAEs occur because of the formation of second continuum minima. Very flat safety factor profiles in higher I _p MAST-U discharges give rise to these minima. They are located at around half of the plasma radius. The GAEs have properties that are very different to those of compressional AEs previously reported for the MAST tokamak with low magnetic fields (Sharapov et al 2014 Phys. Plasmas 21 082501) before the upgrade.

Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under the auspices of a single Task Force called ‘Tokamak Exploitation’. The goal is to benefit from the complementary capabilities of each machine in a coordinated way and help in developing a scientific output scalable to future largre machines. The programme of this Task Force ensures that ASDEX Upgrade, MAST-U, TCV, WEST and JET (since 2022) work together to achieve the objectives of Missions 1 and 2 of the EUROfusion Roadmap: i) demonstrate plasma scenarios that increase the success margin of ITER and satisfy the requirements of DEMO and, ii) demonstrate an integrated approach that can handle the large power leaving ITER and DEMO plasmas. The Tokamak Exploitation task force has therefore organized experiments on these two missions with the goal to strengthen the physics and operational basis for the ITER baseline scenario and for exploiting the recent plasma exhaust enhancements in all four devices (PEX: Plasma EXhaust) for exploring the solution for handling heat and particle exhaust in ITER and develop the conceptual solutions for DEMO. The ITER Baseline scenario has been developed in a similar way in ASDEX Upgrade, TCV and JET. Key risks for ITER such as disruptions and run-aways have been also investigated in TCV, ASDEX Upgrade and JET. Experiments have explored successfully different divertor configurations (standard, super-X, snowflakes) in MAST-U and TCV and studied tungsten melting in WEST and ASDEX Upgrade. The input from the smaller devices to JET has also been proven successful to set-up novel control schemes on disruption avoidance and detachment.

Alfvén Eigenmodes-driven fast-ion flows have been measured for the first time at the ASDEX Upgrade tokamak using an imaging neutral particle analyzer. The flow is such that particles are expelled from the mode location, losing energy as they move outwards. This flow aligns well with the projection of the lines of constant magnetic moment and constant E ′ ( $E^{^{\prime}} = E - \omega P_\phi/n$ , with E being the particle energy, $\omega, n$ the mode frequency and toroidal number and P _φ the toroidal canonical angular momentum). The observed redistributions are consistent with full-orbit simulations performed with the ASCOT5 code, using the mode structure predicted by the linear gyro-kinetic code LIGKA.

MAST-U is equipped with on-axis and off-axis neutral beam injectors (NBI), and these external sources of super-Alfvénic deuterium fast-ions provide opportunities for studying a wide range of phenomena relevant to the physics of alpha-particles in burning plasmas. The MeV range D-D fusion product ions are also produced but are not confined. Simulations with the ASCOT code show that up to 20% of fast ions produced by NBI can be lost due to charge exchange (CX) with edge neutrals. Dedicated experiments employing low field side (LFS) gas fuelling show a significant drop in the measured neutron fluxes resulting from beam-plasma reactions, providing additional evidence of CX-induced fast-ion losses, similar to the ASCOT findings. Clear evidence of fast-ion redistribution and loss due to sawteeth (ST), fishbones (FB), long-lived modes (LLM), Toroidal Alfvén Eigenmodes (TAE), Edge Localised Modes (ELM) and neoclassical tearing modes (NTM) has been found in measurements with a Neutron Camera (NCU), a scintillator-based Fast-Ion Loss Detector (FILD), a Solid-State Neutral Particle Analyser (SSNPA) and a Fast-Ion Deuterium- α (FIDA) spectrometer. Unprecedented FILD measurements in the range of 1–2 MHz indicate that fast-ion losses can be also induced by the beam ion cyclotron resonance interaction with compressional or global Alfvén eigenmodes (CAEs or GAEs). These results show the wide variety of scenarios and the unique conditions in which fast ions can be studied in MAST-U, under conditions that are relevant for future devices like STEP or ITER.

Recent results from MAST Upgrade are presented, emphasising understanding the capabilities of this new device and deepening understanding of key physics issues for the operation of ITER and the design of future fusion power plants. The impact of MHD instabilities on fast ion confinement have been studied, including the first observation of fast ion losses correlated with Compressional and Global Alfvén Eigenmodes. High-performance plasma scenarios have been developed by tailoring the early plasma current ramp phase to avoid internal reconnection events, resulting in a more monotonic q profile with low central shear. The impact of m / n = 3/2, 2/1 and 1/1 modes on thermal plasma confinement and rotation profiles has been quantified, and scenarios optimised to avoid them have transiently reached values of normalised beta approaching 4.2. In pedestal and ELM physics, a maximum pedestal top temperature of ∼350 eV has been achieved, exceeding the value achieved on MAST at similar heating power. Mitigation of type-I ELMs with n = 1 RMPs has been observed. Studies of plasma exhaust have concentrated on comparing conventional and Super-X divertor configurations, while X-point target, X-divertor and snowflake configurations have been developed and studied in parallel. In L-mode discharges, the separatrix density required to detach the outer divertors is approximately a factor 2 lower in the Super-X than the conventional configuration, in agreement with simulations. Detailed analysis of spectroscopy data from studies of the Super-X configuration reveal the importance of including plasma-molecule interactions and D _2 Fulcher band emission to properly quantify the rates of ionisation, plasma-molecule interactions and volumetric recombination processes governing divertor detachment. In H-mode with conventional and Super-X configurations, the outer divertors are attached in the former and detached in the latter with no impact on core or pedestal confinement.

Observations of enhanced fast-ion losses during edge localized modes (ELMs) have been reported in the ASDEX Upgrade tokamak, revealing losses above the injection energy. This suggests that fast ions can be accelerated and lost due to the ELMs. Recent analysis of the ELM-induced losses suggests that the fast ions are lost due to a resonant interaction with the electromagnetic perturbation during the ELM crash. The fast-ion transport and acceleration during ELMs is modelled using electromagnetic fields computed using the hybrid kinetic-MHD code MEGA, while fast-ion full orbits are tracked with the ASCOT code. Time-evolving 3D electromagnetic fields have been implemented in ASCOT to compute fast-ion orbits in the presence of fast MHD events such as ELMs. The simulations successfully reproduce a field-aligned pattern of the losses on the tokamak wall and the formation of an accelerated population in the lost fast-ion distribution, while they predict an accelerated population in the confined distribution. A parametric study of the fast-ion constants of motion suggests a resonant interaction between the fast-ions and the electromagnetic fields arising during the ELM crash. In the case of fast-ion acceleration, the perpendicular electric perturbation, with scales smaller than the fast-ion gyroradius, breaks magnetic moment conservation and resonantly modifies the fast-ion energy.

Experimental methods capable of selectively probing water at the DNA minor groove, major groove, and phosphate backbone are crucial for understanding how hydration influences DNA structure and function. Chiral-selective sum frequency generation spectroscopy (chiral SFG) is unique among vibrational spectroscopies because it can selectively probe water molecules that form chiral hydration structures around biomolecules. However, interpreting chiral SFG spectra is challenging since both water and the biomolecule can produce chiral SFG signals. Here, we combine experiment and computation to establish a theoretical framework for the rigorous interpretation of chiral SFG spectra of DNA. We demonstrate that chiral SFG detects the N-H stretch of DNA base pairs and the O-H stretch of water, exclusively probing water molecules in the DNA first hydration shell. Our analysis reveals that DNA transfers chirality to water molecules only within the first hydration shell, so they can be probed by chiral SFG spectroscopy. Beyond the first hydration shell, the electric field-induced water structure is symmetric and, therefore, precludes chiral SFG response. Furthermore, we find that chiral SFG can differentiate chiral subpopulations of first hydration shell water molecules at the minor groove, major groove, and phosphate backbone. Our findings challenge the scientific perspective dominant for more than 40 years that the minor groove "spine of hydration" is the only chiral water structure surrounding the DNA double helix. By identifying the molecular origins of the DNA chiral SFG spectrum, we lay a robust experimental and theoretical foundation for applying chiral SFG to explore the chemical and biological physics of DNA hydration., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Population growth in recent years has led to increased wastewater production and pollution of water resources. This situation also heavily affects Bolivia, so wastewater treatment methods and materials suitable for Bolivian society should be explored. This study investigated the natural Bolivian Zeolite (BZ) and its NaCl-modified structure (NaBZ) as adsorbents for cadmium removal from water. The natural BZ and the modified form NaBZ were investigated by different physicochemical characterization techniques. Furthermore, XPS and FT-IR techniques were used to investigate the adsorption mechanisms. The cadmium adsorption on BZ and NaBZ was analyzed using various mathematical models, and the Langmuir model provided a better description of the experimental adsorption data with cadmium adsorption capacities of 20.2 and 25.6 mg/g for BZ and NaBZ, respectively. The adsorption followed the pseudo-second order kinetics. The effect of different parameters, such as initial cadmium concentration and pH on the adsorption was studied. In addition, the results of the regeneration test indicated that both BZ and NaBZ can be regenerated by using hydrochloric acid (HCl). Finally, the adsorption experiment of BZ and NaBZ on a real water sample (brine from Salar de Uyuni salt flat) containing a mixture of different heavy metals was carried out. The results obtained in this study demonstrate the effectiveness of natural BZ and modified NaBZ in the removal of heavy metals from wastewater., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Water pollution has jeopardized human health, and a safe supply of drinking water has been recognized as a worldwide issue. The increase in the accumulation of heavy metals in water from different sources has led to the search for efficient and environmentally friendly treatment methods and materials for their removal. Natural zeolites are promising materials for removing heavy metals from different sources contaminating the water. It is important to know the structure, chemistry, and performance of the removal of heavy metals from water, of the natural zeolites to design water treatment processes. This review focuses on critical analyses of the application of distinct natural zeolites for the adsorption of heavy metals from water, specifically, arsenic (As(III), As(V)), cadmium (Cd(II)), chromium (Cr(III), Cr(VI)), lead (Pb(II)), mercury(Hg(II)) and nickel (Ni(II)). The reported results of heavy-metal removal by natural zeolites are summarized, and the chemical modification of natural zeolites by acid/base/salt reagent, surfactants, and metallic reagents has been analyzed, compared, and described. Furthermore, the adsorption/desorption capacity, systems, operating parameters, isotherms, and kinetics for natural zeolites were described and compared. According to the analysis, clinoptilolite is the most applied natural zeolite to remove heavy metals. It is effective in removing As, Cd, Cr, Pb, Hg, and Ni. Additionally, an interesting fact is a variation between the natural zeolites from different geological origins regarding the sorption properties and capacities for heavy metals suggesting that natural zeolites from different regions of the world are unique., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Understanding the role of water in biological processes remains a central challenge in the life sciences. Water structures in hydration shells of biomolecules are difficult to study in situ due to overwhelming background from aqueous environments. Biological interfaces introduce additional complexity because biomolecular hydration differs at interfaces compared to bulk solution. Here, we perform experimental and computational studies of chiral sum frequency generation (chiral SFG) spectroscopy to probe chirality transfer from a protein to the surrounding water molecules. This work reveals that chiral SFG probes the first hydration shell around the protein almost exclusively. We explain the selectivity to the first hydration shell in terms of the asymmetry induced by the protein structure and specific protein-water hydrogen-bonding interactions. This work establishes chiral SFG as a powerful technique for studying hydration shell structures around biomolecules at interfaces, presenting new possibilities to address grand research challenges in biology, including the molecular origins of life., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

The buried solid/liquid interface between hydrophilic fused silica and binary solvent mixtures of acetonitrile (MeCN) and methanol (MeOH) was studied with vibrational sum-frequency generation (vSFG) spectroscopy. Our data showed that at high relative concentrations of methanol, the Fermi resonance peak in the vSFG spectrum is greatly suppressed, and it progressively gains intensity as methanol is diluted with perdeuterated acetonitrile. This phenomenon is quantified by the Fermi resonance coupling coefficient, W , extracted using a two-level model, as well as the experimental intensity ratio, R , of the methyl Fermi resonance band to that of the symmetric stretch. At a 1.0 MeOH mole fraction, W and R values were 10 ± 10 cm -1 and 0.01 ± 0.02, respectively, whereas at a 0.1 mole fraction, W and R increased to 46 ± 4 cm -1 and 0.43 ± 0.16, respectively. This indicates that solvation with acetonitrile effectively tunes the Fermi coupling of methanol vibrations at the silica/liquid interface.

The reactivity of graphene at its boundary region has been imaged using non-linear spectroscopy to address the controversy whether the terraces of graphene or its edges are more reactive. Graphene was functionalised with phenyl groups, and we subsequently scanned our vibrational sum-frequency generation setup from the functionalised graphene terraces across the edges. A greater phenyl signal is clearly observed at the edges, showing evidence of increased reactivity in the boundary region. We estimate an upper limit of 1 mm for the width of the CVD graphene boundary region.

Doubly resonant infrared-visible sum-frequency generation (DR-IVSFG) spectroscopy, encompassing coupled vibrational and electronic transitions, provides a powerful method to gain a deep understanding of nuclear motion in photoresponsive surface adsorbates and interfaces. Here, we use DR-IVSFG to elucidate the role of vibronic coupling in a surface-confined donor-acceptor substituted azobenzene. Our study reveals some unique features of DR-IVSFG that have not been previously reported. In particular, vibronic coupling resulted in prominent SFG signal enhancement of selective stretching modes that reveal electronic properties of coexisting photochromic isomers. Our analysis explores two concepts: (1) In partially isomerized azobenzene at the surface, coupling of the fundamental vibrations to the S 0 → S 1 transition is more prominent for the cis isomer due to symmetry breaking, whereas coupling to the S 0 → S 2 transition was dominant in the trans isomer. (2) A strong coupling between the fundamental vibrations and the valence π-electron density, promoted by the initial absorption of an infrared photon, may result in suppression of the intensity of the hot band vibronic transition. This may translate into a suppressed sum-frequency generation signal at sum frequency wavelengths resonant with the S 0 → S 2 transition of the trans isomer. The weaker coupling of the fundamental vibrations to the non-bonding electron density localized on the azo group can therefore produce detectable sum-frequency generation at the resonance wavelength of the weaker S 0 → S 1 transition in the cis form. These results are explained in the framework of a linear coupling model, involving both Franck-Condon and Herzberg-Teller coupling terms. Our theoretical analysis reveals the important role played by molecular conformation, orientation, and vibronic interference in DR-SFG spectroscopy.

We report direct spectroscopic measurements of the macromolecular organization of ionic surfactants on the surface of semiconducting single-walled carbon nanotubes (SWCNTs) within solution-processed thin films. By using vibrational sum frequency generation (VSFG) spectroscopy, sensitive measurements of interfacial surfactant ordering were obtained as a function of surfactant concentration for sodium dodecyl sulfate (SDS)-encapsulated (6,5) and (7,6) SWCNTs with and without excess electrolytes. Anionic surfactants are known to effectively stabilize SWCNTs. The current models suggest a strong influence of the dispersion conditions on the surfactant interfacial macromolecular organization and self-assembly. Direct experimental probes of such an organization using nanotubes of specific chirality are needed to validate the existing models. We found that as the bulk SDS concentration increases near the surfactant critical micelle concentration, the interfacial ordering increased, approaching the formation of cylindrical-like micelles with the nanotube at the core. At the higher surfactant concentrations measured here, the (6,5) SWCNTs produced more ordered structures relative to those with the (7,6) SWCNTs. The relatively larger-diameter (7,6) chiral tubes support enhanced van der Waals (vdW) interactions between the tube carbon surface and the surfactant methylene chain groups that likely increase the density of gauche defects. A new effect arises when the precursor solution is exposed to a small concentration of divalent Ca 2+ counterions. We postulate that a salt-bridging configuration on such highly curved surfaces decreases the ordering of interfacial surfactant molecules, resulting in compact, disordered structures. However, this phenomenon was not observed with excess Na + ions at the same ionic strength. Instead, a modest increase in surfactant ordering was observed with the excess monovalent electrolyte. These results provide new insights for thin film solution processing of vdW nanomaterials and demonstrate that VSFG is a sensitive probe of surfactant organization on nanostructures.

We present doubly-resonant sum frequency generation (DR-SFG) spectra of fullerene thin films on metallic and dielectric substrates as a way to investigate the interplay between nuclear and electronic coupling at buried interfaces. Modal and substrate selectivity in the electronic enhancement of the C 60 vibrational signatures is demonstrated for excitation wavelengths spanning the visible range. While the SFG response of the totally symmetric A g (2) mode of fullerene is distinctly coupled to the optically allowed electronic transition corresponding to the HOMO-LUMO+1 of C 60 (ca. 2.6 eV), the T 1u (4) vibrational mode appears to be coupled to a symmetry-forbidden HOMO-LUMO transition at lower energies (ca. 2.0 eV). For dielectric substrates, the DR-SFG intensity of the T 1u (4) mode shows lack of enhancement for upconversion wavelengths off-resonance with the optically-dark LUMO. However, the T 1u (4) mode shows a unique coupling to an intermediate state (∼2.4 eV) only for the fullerene films on the gold substrate. We attribute this coupling to unique interactions at the buried C 60 /gold interface. These results demonstrate the occurrence of clear electron-phonon couplings at the C 60 /substrate interfaces and shed light on the impact of these couplings on the optical response of electronically excited fullerene. This coupling may influence charge and energy transport in organic electronic devices mediated by vibrational motions. We also demonstrate a potential use of this added selectivity in chemical imaging.

Infrared surface enhanced Raman scattering (SERS) is an attractive technique for the in situ detection of nanoprobes in biological samples due to the greater depth of penetration and reduced interference compared to SERS in the visible region. A key challenge is to understand the surface layer formed in suspension when a specific label is added to the SERS substrate in aqueous suspension. SERS taken at different wavelengths, theoretical calculations, and surface-selective sum frequency generation vibrational spectroscopy (SFG-VS) were used to define the surface orientation and manner of attachment of a new class of infrared SERS labels with a thiopyrylium core and four pendant 2-selenophenyl rings. Hollow gold nanospheres (HGNs) were used as the enhancing substrate and two distinct types of SERS spectra were obtained. With excitation close to resonance with both the near infrared electronic transition in the label (max 826 nm) and the plasmon resonance maximum (690 nm), surface enhanced resonance Raman scattering (SERRS) was obtained. SERRS indicates that the major axis of the core is near to perpendicular to the surface plane and SFG-VS obtained from a dried gold film gave a similar orientation with the major axis at an angle 64-85° from the surface plane. Longer excitation wavelengths give SERS with little or no molecular resonance contribution and new vibrations appeared with significant displacements between the thiopyrylium core and the pendant selenophene rings. Analysis using calculated spectra with one or two rings rotated indicates that two rings on one end are rotated towards the metal surface to give an arrangement of two selenium and one sulphur atoms directly facing the gold structure. The spectra, together with a space filled model, indicate that the molecule is strongly adsorbed to the surface through the selenium and sulphur atoms in an arrangement which will facilitate layer formation.

The molecular self-assembly of surfactants on the surface of single-walled carbon nanotubes (SWCNT) is currently a common strategy for the tuning of nanotube properties and the stabilization of carbon nanotube dispersions. Here, we report direct measurements of the degree of interfacial ordering for sodium dodecyl sulfate (SDS) surfactants adsorbed on colloidal, single-chirality enriched, SWCNTs within a solid film and investigate the dependence of surface alkyl chain order on the surfactant concentration in the precursor solution. The degree of order for the SWCNT-bound SDS molecules, is probed by vibrational sum frequency generation (VSFG) spectroscopy. We find concrete evidence for the presence of highly ordered surface structures at sufficiently high SDS concentrations, attributed here to cylindrical-like micelle assemblies with the SWCNT at the core. As the SDS concentration decreases, the interfacial order is found to decrease as well, generating a more disordered or random adsorption of surfactants on the nanotube surfaces.

Objective: To evaluate the treatment options and surgical outcomes of long-segment urethral strictures-a review of the largest, international, multi-institutional series., Methods: A retrospective review was performed of patients treated with strictures ≥8 cm at 8 international centers. Endpoints analyzed included surgical complications and recurrence., Results: Four hundred sixty-six patients were identified. Treatment intervals ranged from December 27, 1984 to November 9, 2013. Dorsal onlay buccal mucosal graft (BMG) was the most common procedure (223, 47.9%); others included first- and second-stage Johanson urethroplasty (162 [34.8%] and 56 [12%], respectively), fasciocutaneous (FC) flaps (8, 1.7%), and a combination flap and graft (17, 3.6%). Overall success was achieved in 361 patients (77.5%) with a mean follow-up of 20 months. Second-stage Johanson urethroplasty was found to have a higher recurrence rate compared with that of 1-stage BMG urethroplasty (35.7% vs 17.5%, respectively; P <.01). This was also true in cases of lichen sclerosus (14.0% vs 47.8%, respectively; P <.01). Otherwise, success rates were similar. Urethroplasties performed with FC flaps had a higher complication rate compared with those without (32% vs 14%, respectively; P = .02). Prior dilation or urethrotomy, higher number of prior dilations or urethrotomies, abnormal voiding cystourethrogram, and skin grafts all portend a higher recurrence rate. On logistic regression analysis, only second-stage Johanson had an increased odds ratio of recurrence compared with that of BMG (2.82 [1.41-5.86])., Conclusion: Long-segment strictures can be treated with high success rates in experienced hands. BMG was more successful than second-stage Johanson urethroplasty. FC flaps, although successful, had high complication rates., (Published by Elsevier Inc.)

Sum-frequency generation vibrational spectroscopy (SFG-VS) can provide detailed information and understanding of the molecular composition, interactions, and orientational and conformational structure of surfaces and interfaces through quantitative measurement and analysis. In this review, we present the current status of and discuss important recent developments in the measurement of intrinsic SFG spectral lineshapes and formulations for polarization measurements and orientational analysis of SFG-VS spectra. The focus of this review is to present a coherent description of SFG-VS and discuss the main concepts and issues that can help advance this technique as a quantitative analytical research tool for revealing the chemistry and physics of complex molecular surfaces and interfaces.

Despite the importance of terpenes in biology, the environment, and catalysis, their vibrational spectra remain unassigned. Here, we present subwavenumber high-resolution broad-band sum frequency generation (HR-BB-SFG) spectra of the common terpene (+)-α-pinene that reveal 10 peaks in the C-H stretching region at room temperature. The high spectral resolution resulted in spectra with more and better resolved spectral features than those of the Fourier transform infrared, femtosecond stimulated Raman spectra in the bulk condensed phase and those of the conventional BB-SFG and scanning SFG spectroscopy of the same molecule on a surface. Experiment and simulation show the spectral line shapes with HR-BB-SFG to be accurate. Homogeneous vibrational decoherence lifetimes of up to 1.7 ps are assigned to specific oscillators and compare favorably to lifetimes computed from density functional tight binding molecular dynamics calculations. Phase-resolved spectra provided their orientational information. We propose the new spectroscopy as an attractive alternative to time domain vibrational spectroscopy or heterodyne detection schemes for studying vibrational energy relaxation and vibrational coherences in molecules at molecular surfaces or interfaces.

The lack of understanding of the temporal effects and the restricted ability to control experimental conditions in order to obtain intrinsic spectral lineshapes in surface sum-frequency generation vibrational spectroscopy (SFG-VS) have limited its applications in surface and interfacial studies. The emergence of high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS) with sub-wavenumber resolution [Velarde et al., J. Chem. Phys., 2011, 135, 241102] offers new opportunities for obtaining and understanding the spectral lineshapes and temporal effects in SFG-VS. Particularly, the high accuracy of the HR-BB-SFG-VS experimental lineshape provides detailed information on the complex coherent vibrational dynamics through direct spectral measurements. Here we present a unified formalism for the theoretical and experimental routes for obtaining an accurate lineshape of the SFG response. Then, we present a detailed analysis of a cholesterol monolayer at the air/water interface with higher and lower resolution SFG spectra along with their temporal response. With higher spectral resolution and accurate vibrational spectral lineshapes, it is shown that the parameters of the experimental SFG spectra can be used both to understand and to quantitatively reproduce the temporal effects in lower resolution SFG measurements. This perspective provides not only a unified picture but also a novel experimental approach to measuring and understanding the frequency-domain and time-domain SFG response of a complex molecular interface.

While in principle the frequency-domain and time-domain spectroscopic measurements should generate identical information for a given molecular system, the inhomogeneous character of surface vibrations in sum-frequency generation vibrational spectroscopy (SFG-VS) studies has only been studied with time-domain SFG-VS by mapping the decay of the vibrational polarization using ultrafast lasers, this due to the lack of SFG vibrational spectra with high enough spectral resolution and accurate enough lineshape. Here, with the recently developed high-resolution broadband SFG-VS (HR-BB-SFG-VS) technique, we show that the inhomogeneous lineshape can be obtained in the frequency-domain for the anchoring CN stretch of the 4-n-octyl-4'-cyanobiphenyl (8CB) Langmuir monolayer at the air-water interface, and that an excellent agreement with the time-domain SFG free-induction-decay can be established. We found that the 8CB CN stretch spectrum consists of a single peak centered at 2234.00 ± 0.01 cm(-1) with a total linewidth of 10.9 ± 0.3 cm(-1) at half maximum. The Lorentzian contribution accounts only for 4.7 ± 0.4 cm(-1) to this width and the Gaussian (inhomogeneous) broadening for as much as 8.1 ± 0.2 cm(-1). Polarization analysis of the -CN spectra showed that the -CN group is tilted 57° ± 2° from the surface normal. The large heterogeneity in the -CN spectrum is tentatively attributed to the -CN group interactions with the interfacial water molecules penetrated/accommodated into the 8CB monolayer, a unique phenomenon for the nCB Langmuir monolayers reported previously.

Objective: Present the case of a patient with a discontinuous intrabdominal splenogonadal fusion with an associated germ cell tumor., Methods: A case of a man of 29 years with bilateral cryptorchidism and left intra-abdominal discontinuous splenogonadal fusion associated with seminoma as an accidental finding in the context of a robotic pyeloplasty due to ipsilateral ureteropelvic junction stenosis., Results: The total operative time was 80 minutes (atrophic gonad removal and pyeloplasty by the Anderson-Hynes technique) with an estimated blood loss less than 100 cc. The hospitalization time was less than 36 hrs. The pathology and immunohistochemical report was compatible with intratubular germ cell neoplasia (seminoma)., Conclusion: The splenogonadal fusion is an uncommon pathology. While a high clinical suspicion may avoid unnecessary orchiectomy in young patients, its association with disorders such as cryptorchidism should make us suspect the possible presence of a concomitant germ cell neoplasia.

The ability to achieve sub-wavenumber resolution (0.6 cm(-1)) and a large signal-to-noise ratio in high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS) allows for the detailed SFG spectral lineshapes to be used in the unambiguous determination of fine spectral features. Changes in the structural spectroscopic phase in SFG-VS as a function of beam polarization and experimental geometry proved to be instrumental in the identification of an unexpected 2.78 ± 0.07 cm(-1) spectral splitting for the two methyl groups at the vapor/dimethyl sulfoxide (DMSO, (CH(3))(2)SO) liquid interface as well as in the determination of their orientational angles.

We report kinetic energy distributions of exoelectrons produced by collisions of highly vibrationally excited NO molecules with a low work function Cs dosed Au(111) surface. These measurements show that energy dissipation pathways involving nonadiabatic conversion of vibrational energy to electronic energy can result in electronic excitation of more than 3 eV, consistent with the available vibrational energy. We measured the dependence of the electron energy distributions on the translational and vibrational energy of the incident NO and find a clear positive correlation between final electron kinetic energy and initial vibrational excitation and a weak but observable inverse dependence of electron kinetic energy on initial translational energy. These observations are consistent with a vibrational autodetachment mechanism, where an electron is transferred to NO near its outer vibrational turning point and ejected near its inner vibrational turning point. Within the context of this model, we estimate the NO-to-surface distance for electron transfer.

The objective of the article is to provide the socio-cultural, political, economic, and geographic conditions that justified a regional effort for training maternal and child health (MCH) professionals in the Rocky Mountain region, describe a historical account of factors that led to the development of the Rocky Mountain Public Health Education Consortium (RMPHEC), and present RMPHEC as a replicable model developed to enhance practice/academic partnerships among state, tribal, and public health agencies and universities to enhance public health capacity and MCH outcomes. This article provides a description of the development of the RMPHEC, the impetus that drove the Consortium's development, the process used to create it, and its management and programs. Beginning in 1997, local, regional, and federal efforts encouraged stronger MCH training and continuing education in the Rocky Mountain Region. By 1998, the RMPHEC was established to respond to the growing needs of MCH professionals in the region by enhancing workforce development through various programs, including the MCH Certificate Program, MCH Institutes, and distance learning products as well as establishing a place for professionals and MCH agencies to discuss new ideas and opportunities for the region. Finally over the last decade local, state, regional, and federal efforts have encouraged a synergy of MCH resources, opportunities, and training within the region because of the health disparities among MCH populations in the region. The RMPHEC was founded to provide training and continuing education to MCH professionals in the region and as a venue to bring regional MCH organizations together to discuss current opportunities and challenges. RMPHEC is a consortium model that can be replicated in other underserved regions, looking to strengthen MCH training and continuing education.

This is one of six short papers that describe additional innovations to help integrate public health into medical education; these were featured in the "Patients and Populations: Public Health in Medical Education" conference. They represent relatively new endeavors or curricular components that had not been explored in prior publications. Although evaluation data are lacking, it was felt that sharing a description of a longitudinal curriculum focused on the development of basic advocacy skills through practical activities in community assessment and engagement combined with legislative advocacy at the University of New Mexico would be of value to medical educators., (Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Substantial progress has been made in the quantitative understanding and interpretation of the hydrogen bonding and ordering structure of the air/water interface since the first sum-frequency generation vibrational spectroscopy (SFG-VS) measurement by Q. Du et al. in 1993 (Phys. Rev. Lett. 1993, 70, 2312-2316). However, there are still disagreements and controversies on the consistency between the different experimental measurements, as well as in the theoretical and computational results. One critical problem lies in the lack of consistency between the SFG-VS intensity measurements and the recently developed SFG-VS phase spectra measurements of the neat air/water interface, which has inspired various theoretical efforts. In this report, the reliability of the SFG-VS intensity spectra of the air/neat water interface is to be quantitatively examined, and possible sources of inaccuracies in the SFG-VS phase spectral measurement are to be discussed based on the nonresonant SHG phase measurements. Solid evidence is shown indicating that the SFG-VS intensity spectra from different laboratories are now quantitatively converging and in agreement with each other. However, the possible inaccuracies and inconsistencies in the SFG-VS phase spectra measurements need to be carefully examined against a properly corrected phase standard to take full advantage of this powerful experimental tool., (© 2011 American Chemical Society)

The photoelectron spectrum of the oxyallyl (OXA) radical anion has been measured. The radical anion has been generated in the reaction of the atomic oxygen radical anion (O(•-)) with acetone. Three low-lying electronic states of OXA have been observed in the spectrum. Electronic structure calculations have been performed for the triplet states ((3)B(2) and (3)B(1)) of OXA and the ground doublet state ((2)A(2)) of the radical anion using density functional theory (DFT). Spectral simulations have been carried out for the triplet states based on the results of the DFT calculations. The simulation identifies a vibrational progression of the CCC bending mode of the (3)B(2) state of OXA in the lower electron binding energy (eBE) portion of the spectrum. On top of the (3)B(2) feature, however, the experimental spectrum exhibits additional photoelectron peaks whose angular distribution is distinct from that for the vibronic peaks of the (3)B(2) state. Complete active space self-consistent field (CASSCF) method and second-order perturbation theory based on the CASSCF wave function (CASPT2) have been employed to study the lowest singlet state ((1)A(1)) of OXA. The simulation based on the results of these electronic structure calculations establishes that the overlapping peaks represent the vibrational ground level of the (1)A(1) state and its vibrational progression of the CO stretching mode. The (1)A(1) state is the lowest electronic state of OXA, and the electron affinity (EA) of OXA is 1.940 ± 0.010 eV. The (3)B(2) state is the first excited state with an electronic term energy of 55 ± 2 meV. The widths of the vibronic peaks of the X̃ (1)A(1) state are much broader than those of the ã (3)B(2) state, implying that the (1)A(1) state is indeed a transition state. The CASSCF and CASPT2 calculations suggest that the (1)A(1) state is at a potential maximum along the nuclear coordinate representing disrotatory motion of the two methylene groups, which leads to three-membered-ring formation, i.e., cyclopropanone. The simulation of b̃ (3)B(1) OXA reproduces the higher eBE portion of the spectrum very well. The term energy of the (3)B(1) state is 0.883 ± 0.012 eV. Photoelectron spectroscopic measurements have also been conducted for the other ion products of the O(•-) reaction with acetone. The photoelectron imaging spectrum of the acetylcarbene (AC) radical anion exhibits a broad, structureless feature, which is assigned to the X̃ (3)A'' state of AC. The ground ((2)A'') and first excited ((2)A') states of the 1-methylvinoxy (1-MVO) radical have been observed in the photoelectron spectrum of the 1-MVO ion, and their vibronic structure has been analyzed.

We report the first direct measurement of the kinetic energy of exoelectrons produced by collisions of vibrationally excited molecules with a low work function metal surface exhibiting electron excitations of 64% (most probable) and 95% (maximum) of the initial vibrational energy. This remarkable efficiency for vibrational-to-electronic energy transfer is in good agreement with previous results suggesting the coupling of multiple vibrational quanta to a single electron.

Electronic structure of the oxyallyl diradical and the anion is investigated using high-level ab initio methods. Converged theoretical estimates of the energy differences between low-lying electronic states of oxyallyl (OXA) as well as detachment energies of the anion are reported. Our best estimates of the adiabatic energy differences between the anion (2)A(2) and the neutral (3)B(2) and (3)B(1) states are 1.94 and 2.73 eV, respectively. The (1)A(1) state lies above (3)B(2) vertically, but geometric relaxation brings it below the triplet. The two-dimensional scan of the singlet (1)A(1) potential energy surface (PES) reveals that there is no minimum corresponding to a singlet diradical structure. Thus, singlet OXA undergoes prompt barrierless ring closure. However, a flat shape of the PES results in the resonance trapping in the Franck-Condon region, giving rise to the experimentally observable features in the photoelectron spectrum. By performing reduced-dimensionality wave packet calculations, we estimated that the wave packet lingers in the Franck-Condon region for about 170 fs, which corresponds to the spectral line broadening of about 200 cm(-1). We also present calculations of the photodetachment spectrum and compare it with experimental data. Our calculations lend strong support to the assignment of the photoelectron spectrum of the OXA anion reported in Ichino et al. (Angew. Chem., Int. Ed. Engl. 2009, 48, 8509).