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The geometric and electronic structures of a monolayer of rubrene and of a fluorinated rubrene derivative (FM-rubrene), adsorbed on a Ag(100) surface, were determined using scanning tunneling microscopy (STM), ultraviolet photoemission spectroscopy (UPS), and inverse photoemission spectroscopy (IPS) to study the influence of fluorine-functionalization on self-assembly, molecular energy levels, and energy-level alignment. STM images at room temperature reveal that the molecules form different molecular assemblies at the monolayer coverage and have the tetracene backbones nearly parallel to the surface, with strongly splayed phenyls. While the assemblies are highly ordered, the molecular orientation and intermolecular spacings differ from those of the respective molecular crystals and thus do not act as templates for the epitaxial growth of ordered multilayer molecular films. UPS and IPS measurements indicate that the frontier orbitals of an adsorbed FM-rubrene molecular layer are shifted downward with respect to the Ag(100) Fermi level by 0.2 eV as compared to those of a rubrene monolayer. Moreover, the intrinsic molecular dipole of FM-rubrene contained in the first layer leads to an interface dipole of 0.2 eV, further shifting added molecular layers to higher energies. Comparison of the adsorption of rubrene to that of FM-rubrene on Ag(100) provides valuable insights into the nature of the molecule surface and intermolecular interactions that drive self-assembly and energy-level alignment, as well as their effects on the potential growth of ordered molecular multilayers.

Despite advances in multiple myeloma treatment the disease remains challenging to treat with repeated relapses in most. For high-risk younger patients, allogeneic transplants are occasionally performed. While curative in some, complications can include the development of opportunistic infections and secondary malignancies. Furthermore, patients relapsing after an allogeneic transplant may have poor bone marrow reserve limiting the ability to use subsequent therapies. We describe two patients who underwent a “reverse” autologous peripheral blood stem cell rescue using stem cells banked prior to allogeneic transplantation. The outcomes were successful and led to full engraftment and correction of their immunodeficiencies and pancytopenia respectively.

Multiple Myeloma (MM) patients are often treated with high-dose chemotherapy and autologous stem cell transplantation (ASCT) for disease control. Lenalidomide is typically used as maintenance but results in an estimated 3.3% chance of developing a therapy-related myeloid neoplasm (TMN) typically myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML). This complication is often devastating with a median survival for those with a TMN of just 13 months.

Background

The interactions between zinc(II) tetraphenylporphyrin (ZnTPP) molecules and the Ag(100) and Ag(111) surfaces were investigated using a combination of scanning tunneling microscopy as a local probe of the molecular adsorption configuration and X-ray, ultraviolet, and inverse photoemission spectroscopies as probes of the electronic structure. For each surface, a monolayer of ZnTPP, formed by multilayer desorption, exhibits a highly ordered structure in registry with the underlying surface lattice. Subsequent annealing leads to a transition from intact molecular adsorption to dehydrogenation and subsequent rehybridization. This rehybridization is both intramolecular, with a flattening of the molecules and a measurable alteration of the electronic structure, and intermolecular, leading to two-dimensional growth of extended covalently bound structures.

Dramatic changes taking place locally, regionally, globally, demand that we rethink strategies to improve public health, especially in disadvantaged communities where the cumulative impacts of toxicant exposure and other environmental and social stressors are most damaging. The emergent field of Sustainability Science, including a new bioregionalism for the 21st Century, is giving rise to promising place-based (territorially rooted) approaches. Embedded in this bioregional approach is an integrated planning framework (IPF) that enables people to map and develop plans and strategies that cut across various scales (e.g. from regional to citywide to neighborhood scale) and various topical areas (e.g. urban land use planning, water resource planning, food systems planning and “green infrastructure” planning) with the specific intent of reducing the impacts of toxicants to public health and the natural environment. This paper describes a case of bioregionally inspired integrated planning in San Diego, California (USA). The paper highlights food-water-energy linkages and the importance of “rooted” community-university partnerships and knowledge-action collaboratives in creating healthy and just bioregions.

AbstractCost, constraints, and perseverance—three closely related terms in the serious leisure perspective (SLP)—have been identified by Lamont, Kennelly, and Moyle (2015) as in need of some clarification. This note attempts to clarify the relationship of the three, based on how they have been defined and interrelated over the years in the SLP. The concepts of constraint and cost play a number of different roles in the SLP. It therefore seems best to retain them as separate ideas, despite the doubts raised by Lamont and colleagues. Perseverance also plays a couple of roles in the SLP, which likewise justifies keeping the idea separate from cost and constraint, again contrary to the doubts posed by Lamont and colleagues.

Gold nanorods and their core–shell nanocomposites have been widely studied because of their well-defined anisotropy and unique optical properties and applications. This study demonstrates a facile hydrothermal synthesis strategy for generating carbon coating on gold nanorods (AuNRs@C) under mild conditions (<200 °C), where the carbon shell is composed of polymerized sugar molecules (glucose). The structure and composition of the produced core–shell nanocomposites were characterized using advanced microscopic and spectroscopic techniques. The functional properties, particularly the photothermal and biocompatibility properties of the produced AuNRs@C, were quantified to assess their potential in photothermal hyperthermia. These AuNRs@C were tested in vitro (under representative treatment conditions) using near-infrared (NIR) light irradiation. It was found that the AuNRs produced here exhibit exemplary heat generation capability. Temperature changes of 10.5, 9, and 8 °C for AuNRs@C were observed with carbon shell thicknesses of 10, 17, and 25 nm, respectively, at a concentration of 50 μM, after 600 s of irradiation with a laser power of 0.17 W/cm2. In addition, the synthesized AuNRs@C also exhibit good biocompatibility toward two soft tissue sarcoma cell lines (HT1080, a fibrosarcoma; and GCT, a fibrous histiocytoma). The cell viability study shows that AuNRs@C (at a concentration of <0.1 mg/mL) core–shell particles induce significantly lower cytotoxicity on both HT1080 and GCT cell lines, as compared with cetyltrimethylammonium bromide (CTAB)-capped AuNRs. Furthermore, similar to PEG-modified AuNRs, they are also safe to both HT1080 and GCT cell lines. This biocompatibility results from a surface full of −OH or −COH groups, which are suitable for linking and are nontoxic Therefore, the AuNRs@C represent a viable alternative to PEG-coated AuNRs for facile synthesis and improved photothermal conversion. Overall, these findings open up a new class of carbon-coated nanostructures that are biocompatible and could potentially be employed in a wide range of biomedical applications.

The interaction between zinc(II) tetraphenylporphyrin (ZnTPP) molecules and a Au(111) surface is investigated using scanning tunnel microscopy, from initial adsorption sites to monolayer self-assembly, with a particular emphasis on its relation to the surface atomic structure reorganization. At low coverage, no ZnTPP molecules are observed on terraces, and adsorbates appear to only decorate step edges. At intermediate coverage, ZnTPPs adsorb into self-organized islands of flat-lying macrocycles in quasi-registry with the underlying surface reconstruction, in areas delimited by herringbone reconstruction domain walls. At monolayer coverage, the adsorption geometry of the self-organized molecular layer can be fully characterized with respect to the atomic structure of Au(111) surface atoms. Moreover alteration of the Au(111) surface reconstruction domain size is observed, caused by an adsorbate-induced reduction of the Au(111) surface stress anisotropy. This behavior is not ubiquitous to ZnTPP monolayers as a monolayer prepared from the desorption of a ZnTPP multilayer does not alter the domain size of the Au(111) surface. In this case, the additional thermal energy leads to a complete rearrangement of the self-assembled structure, and the surface stress anisotropy returns to its value for the clean surface.

A chromophore–bridge–anchor molecular architecture is used to manipulate the molecular level energy position, with respect to the band edges of the substrate, of a chromophore bound to a surface via an anchor group. An energy shift of the chromophore’s frontier orbitals is induced by the addition of an oriented molecular dipole into the bridge part of the compound. This principle has been tested using three Zinc Tetraphenylporphyrin derivatives of comparable structure: two of which possess a dipole, but pointing in opposite directions and, for comparison, a compound without a dipole. UV–vis absorption and emission spectroscopies have been used to probe the electronic structure of the compounds in solution, while UV photoemission spectroscopy has been used to measure the relative position of the molecular levels of the chromophore with respect to the band edges of a ZnO(11–20) single crystal substrate. It is shown that the introduction of a molecular dipole does not alter the chromophore’s HOMO–LUMO gap, and that the molecular level alignment of the compounds bound to the ZnO surface follows the behavior predicted by a simple parallel-plate capacitor model.

The relation between energy alignment, adsorption geometry, and electron transfer between a chromophore and an oxide surface has been explored for a series of Zn(II) tetraphenylporphyrin derivatives adsorbed on TiO2(110) and ZnO(112̅0) surfaces. The electronic occupied and unoccupied structure has been obtained using UV-photoemission and inverse photoemission spectroscopies. From these results, a full picture of the energetics at the chromophore–oxide interface was established. The alignment of the molecular levels relevant for optical transition was found independent of the functionalization of the meso-phenyl groups. However, to explain the observation of different optical properties and electron transfer efficiencies of these different dyes, the adsorption geometry of two of these dyes was determined using scanning tunnel microscopy and near edge absorption fine structure spectroscopy. Functionalization of the meso-phenyls with COOH groups in the meta-position results in the ZnP macrocycle adsorbed parallel to the surface. Functionalization of the meso-phenyl groups with COOH groups in the para position results in a bounding geometry where the ZnP macrocycle makes an angle of ∼50° from the surface normal. This geometry, which allows face-to-face stacking of the porphyrin rings, opens a new electronic channel for exciton delocalization that competes with direct electron injection into the substrate conduction band.

The chemical and structural phase evolution of ultrathin (∼5 nm) FeF2films upon deposition of atomic lithium in an ultrahigh vacuum environment has been studied using X-ray and UV photoemission spectroscopies, inverse photoemission spectroscopy, and transmission electron microscopy in an effort to explore the fundamental properties of the conversion reaction of this promising Li battery cathode material. Spectroscopic measurements show reduction of FeF2into a metallic Fe0phase and a LiF phase upon Li deposition. No other phases are detected. Transmission electron microscopy reveals extensive changes in the film’s morphology and material reorganization upon full lithiation. The initial FeF2film, with grains on the order of 10 nm in diameter, phase separates into smaller (∼3 nm) interconnected Fe0regions surrounded by LiF. This structural modification is attributed to the large Li+ionic mobility with respect to Fe2+. The intrinsic nanoscale texture of the final phases is believed to aid in accommodating the extensive structural transformations that occur in this conversion reaction material during an electrochemical cycle in battery applications.

Underlying auditory processes in speech perception were explored. Specifically of interest were the stages of auditory processing involved in the integration of dynamic information in nontraditional speech cues such as the virtual formant transitions. These signals utilize intensity ratio cues and changes in spectral center-of-gravity (instead of the actual formant frequency transitions) to produce perceived F3 glides. 6 men and 8 women (Mage = 24.2 yr., SD= 2.1), recruited through posted materials from graduate students at The Ohio State University, participated in two experiments. The results for frequency-based formant transitions (Exp. 1) indicated that spectral cues to syllable identification are combined at more central levels of auditory processing. However, when the components of the virtual formant stimuli were divided between the ears in a dichotic listening task (Exp. 2), the results indicated that auditory spectral integration may occur above the auditory periphery but at stages more intermediate rather than central.

Several letters to the editor are presented in response to articles in previous issues including "2001: A Space Odyssey," by Robert Skotak which appeared in the journal's 25th anniversary issue, a query about the current address of "UFO Magazine" and "Spielberg and the UFO Connection" which also appeared in the journal's 25th anniversary issue.

The electronic structure of the Zn(II)-5-(3,5-dicarboxyphenyl)-10,15,20-triphenylporphyrin dye (ZnTPP-Ipa), chemisorbed onto ZnO(112̅0) and TiO2(110) single-crystal surfaces, has been investigated by means of density functional theory (DFT) and by electron spectroscopy methods in an ultra-high-vacuum environment. The core levels (Ti 2p and Zn 2p) as well as the valence band have been probed using X-ray and ultraviolet photoemission spectroscopies, whereas the conduction band has been evaluated from inverse photoemission spectroscopy. The calculated density of states for the gas phase molecule compares well to the experimentally determined electronic structure, allowing both a simple understanding of the adsorbate electronic properties and a direct determination of the ZnTPP-Ipa frontier orbitals with respect to the substrates’ band edges.

We have previously demonstrated improved medical student performance using standardized live patient models in the Trauma Evaluation and Management (TEAM) program. The trauma manikin has also been offered as an option for teaching trauma skills in this program. In this study, we compare performance using both models.

Advancements in electronic data acquisition have translated into improved monitoring of victims of cardiac arrest, but initial techniques remain direct observation of pulses and respirations. The most essential monitor continues to be the electrocardiogram. However, monitoring diastolic blood pressure, myocardial perfusion pressure, and end-tidal carbon dioxide are extremely useful. Most of the current research on monitoring during cardiopulmonary resuscitation focuses on methods for analyzing ventricular fibrillation waveforms. By analyzing the waveform, defibrillation shocks may be delivered at the time when the chance of success is optimal. Low-amplitude and low-frequency fibrillation waveforms are associated with increased rates of asystole and pulseless electrical activity after defibrillation. Methods of analyzing the ventricular fibrillation waveform include measuring the amplitude and frequency and combining the contributions of amplitude and frequency by various methods to improve discrimination. Other types of monitoring being studied for their usefulness during cardiac arrests include sonography, Bispectral Index monitoring, tissue carbon dioxide monitors, and pupil observation. The test of these monitoring techniques is ultimately their ability to improve patient survival to hospital discharge, which is a major challenge for resuscitation researchers.

This study examines possible differences between young and older adult listeners in the effect of contextual contrast on vowel identification using a vowel anchoring procedure. All listeners identified a 7-step [i]—[I] continuum under both an equiprobable control condition and an anchoring condition (in which one endpoint stimulus occurred four times more often than any other single stimulus token). Phoneme boundaries in the anchoring condition shifted toward the anchor endpoint, as expected, for both groups, but there was a significant effect of age when [i] served as the anchor. Evidence of an increase in response bias for older adult listeners was also found.

Two experiments were conducted to discover whether the perceptual features obtained in multidimensional scaling studies accurately reflect the acoustic properties of the stimulus vowels or merely aspects of the vowels’ long-term memory prototypes. In each experiment subjects were required to make paired-comparison judgments of vowel stimuli on two sets of stimulus pairs. The stimulus sets were composed of the same phonetic qualities but differed in terms of subphonemic (acoustic) characteristics. Multivariant analysis of variance indicated that subjects’ perceptual distance judgments were sensitive to the subphonemic as well as phonemic distinctions among the stimuli. The perceptual spaces extracted using INDSCAL analysis also accurately corresponded to these acoustic space variations. The results are argued to demonstrate the use of covert, subphonemic, categories during the paired-comparison task.

This study was designed to investigate the effect of speaker's voice quality on perceived phonetic quality in vowels using a perceptual scaling task. 16 subjects scaled sets of vowels produced by six different speakers (three women, three men). Analysis indicated no significant influence of speakers' quality on judgments of similarity of vowels. Results suggest that judgments of similarity were made on the basis of linguistically categorized images.

This study examines possible differences between young and older adult listeners in the effect of contextual contrast on vowel identification using a vowel anchoring procedure. All listeners identified a 7-step [i]—[I] continuum under both an equiprobable control condition and an anchoring condition (in which one end-point stimulus occurred four times more often than any other single stimulus token). Phoneme boundaries in the anchoring condition shifted toward the anchor endpoint, as expected, for both groups, but there was a significant effect of age when [i] served as the anchor. Evidence of an increase in response bias for older adult listeners was also found.

This study investigated the relationship between speech perception and speech production. An experimental technique called motor-motor adaptation was devised. Subjects produced a speech token repeatedly (20 to 40 repetitions), then produced a second token one time. These tokens all contained stop consonants and were subsequently analyzed for voice onset time. The results paralleled previous findings using the experimental procedure, perceptuomotor adaptation. The present study supports the notion of a perception-production link.

A group of Spanish‐ and English‐speaking listeners participated in a multidimensional scaling (MDS) study examining perceptual responses to three Spanish and seven English vowels. The vowel stimuli represented tokens of Spanish /i/, /e/, and /a/ and English /i/, /i/, /ei/, /&Vegr;/, /æ/, /inverted vee/, and /@sa /. Each vowel had been spoken by three monolingual talkers of Spanish or English and all possible vowel pairs (405 pairs) were presented to listeners (excluding pairs representing the same vowel category). Thirty monolingual English listeners and thirty native Spanish listeners who had learned English as a second language rated these vowel pairs on a nine‐point dissimilarity scale. These perceptual distances were then analyzed using the individual‐differences version of ALSCAL. Results demonstrated that the English monolinguals used three underlying dimensions in rating vowels while the Spanish–English bilinguals used just two. The most salient perceptual dimension for both groups distinguished vowel height. However, for the English listeners, this dimension was most significantly correlated with duration and indicated a language‐dependent sensitivity to this phonetic feature. The second dimension for the English listeners represented a front–back distinction, while the third reflected a central/noncentral distinction. For the Spanish listeners, the second dimension was less easily interpreted. However, the perceptual data for the Spanish listeners was more interpretable in terms of the distribution of the vowels in the two‐dimensional perceptual plane. The vowels were distributed in terms of three separate vowel clusters, each cluster near the location of a Spanish vowel. Separate MDS analyses were carried out for subgroups of Spanish listeners who were relatively proficient or nonproficient in English. The vowel space of the proficient Spanish listeners was more Englishlike than that of the nonproficient Spanish listeners, suggesting that the perceptual dimensions used by listeners in identifying vowels may be gradually modified as proficiency in the second language improves.

English monolinguals and native Spanish speakers of English rated the dissimilarity of tokens of two Spanish vowel categories, two English vowel categories, or one Spanish and one English vowel category. The dissimilarity ratings of experienced and inexperienced Spanish subjects did not differ significantly. For both the native Spanish and English subjects, perceived dissimilarity increased as the distance between vowels in an F1−F2 acoustic space increased. This supported the existence of a universal, sensory‐based component in cross‐language vowel perception. The native English and Spanish subjects’ ratings were comparable for pairs made up of vowels that were distant in an F1−F2 space, but not for pairs made up of vowels from categories that were adjacent in an F1−F2 space. The inference that the differential classification of a pair of vowels augments perceived dissimilarity was supported by the results of experiment 2, where subjects rated pairs of vowels and participated in an oddity discrimination task. Triads in the oddity task were made up of tokens of vowel categories that were either adjacent (e.g., /a/–/æ/–/a/) or nonadjacent (e.g., /a/–/i/–/i/) in an F1−F2 space. The native English subjects’ discrimination was better than the native Spanish subjects’ for adjacent but not nonadjacent triads. The better the Spanish subjects performed on adjacent triads—and thus the more likely they were to have differentially classified the two phonetically distinct vowels in the triad—the more dissimilar they had earlier judged realizations of those two categories to be when presented in pairs. Results are discussed in terms of their implications for second language acquisition.

A scaling experiment using dyadic comparisons of vowel pairs was performed to determine if significant perceptual variation existed on an individual level and whether such variation could be correlated with differences among subjects in their production of vowels. Subjects were required to scale six separate sets of vowel stimuli. Each stimulus set consisted of the 36 possible dyads from the vowel set /i, I, e, æ, a, ?, o, Æ, u/. Analysis of the resulting data indicated that significant individual perceptual variation was present which could be seen as a function of perceptual structure differences between the subjects and not merely error variance. In addition, such variations were related to aspects of each subject’s acoustic vowel space – indicators of tongue height and advancement during vowel articulation. These results were interpreted as suggesting a link between perception and production.

The present study examined the influence of unstressed prefixes and suffixes upon the location of stress-beats in the production and perception of stressed CVC syllables. Analysis indicates that the addition of an unstressed suffix produces a small stress-beat shift, while the addition of an unstressed prefix produces a much larger shift in the opposite direction.