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Article originally published in Internet Reference Services Quarterly at https://www.tandfonline.com/doi/full/10.1080/10875301.2021.1946456

David et al . claim that vestibular shape does not reflect function and that we did not use phylogenetic inference methods in our primary analyses. We show that their claims are countered by comparative and direct experimental evidence from across Vertebrata and that their models are empirically unverified. We did use phylogenetic methods to test our hypotheses. Moreover, their phylogenetic correction attempts are methodologically inappropriate.

We investigate Ramanujan congruences for the function which counts the overpartitions of n with restricted odd differences. In particular, we show that only one such congruence exists. Our method involves using the theory of modular forms to prove a more general theorem which bounds the number of primes possible for Ramanujan congruences in certain eta-quotients. This generalizes work done by Jonah Sinick. We also provide two congruences modulo 5 for this function., 14 pages

Recent studies have demonstrated a mechanism of embryonic yolk processing in lizards, snakes and turtles that differs markedly from that of birds. In the avian pattern, cells that line the inside of the yolk sac take up products of yolk digestion and deliver nutrients into the vitelline circulation. In contrast, in squamates and turtles, proliferating endodermal cells invade and fill the yolk sac cavity, forming elongated strands of yolk-filled cells that surround small blood vessels. This arrangement provides a means by which yolk material becomes cellularized, digested, and transported for embryonic use. Ultrastructural observations on late-stage Alligator mississippiensis eggs reveal elongated, vascular strands of endodermal cells within the yolk sac cavity. The strands of cells are intermixed with free yolk spheres and clumps of yolk-filled endodermal cells, features that reflect early phases in the yolk-processing pattern. These observations indicate that yolk processing in Alligator is more like the pattern of other reptiles than that of birds.

Academic libraries face limitations of space, staffing, budget, and other factors, but still must maintain their collections responsibly. Collection maintenance with the goal of reclaiming space re...

In Library Technical Services: Adapting to a Changing Environment, Stacy Marien, Acquisitions Librarian at American University, and co-editor of the Against the Grain column, “Let’s Get Technical,”...

Living birds (Aves) have bodies substantially modified from the ancestral reptilian condition. The avian pelvis in particular experienced major changes during the transition from early archosaurs to living birds

At the 33rd Annual NASIG Conference, Lauren Smith, of the Institute for Research and Innovation in Social Service in Glasgow, Scotland, presented a vision session on the intersections of power, praxis, and privilege in the information sphere. When librarians acknowledge the power and privilege embedded in their creation and use of systems that allow access to information and their expertise in navigating those systems, it allows librarians to practice the beneficent exercise of that power to challenge, modify, and dismantle current power structures if they are injust. Smith explained how the collective use of this power aids librarians in actualizing real change to advance the democratization of information access.

Promoting an institutional repository (IR) to both faculty and end-users can be challenging. We surveyed academic libraries with an IR in Texas, and asked both library administrators and IR...

Ahlgren and Samart relate three cusp forms with complex multiplication to certain weakly holomorphic modular forms using $p$-adic bounds related to their Fourier coefficients. In these three examples, their result strengthens a theorem of Guerzhoy, Kent, and Ono which pairs certain CM forms with weakly holomorphic modular forms via $p$-adic limits. Ahlgren and Samart use only the theory of modular forms and Hecke operators, whereas Guerzhoy, Kent, and Ono use the theory of harmonic Maass forms. Here we extend Ahlgren and Samart's work to all cases where the cusp form space is one-dimensional and has trivial Nebentypus. Along the way, we obtain a duality result relating two families of modular forms that arise naturally in each case., Comment: Submitted 24 February, 2021. 12 pages

The evolutionary radiation of birds has produced incredible morphological variation, including a huge range of skull form and function. Investigating how this variation arose with respect to non-avian dinosaurs is key to understanding how birds achieved their remarkable success after the Cretaceous–Paleogene extinction event. Using a high-dimensional geometric morphometric approach, we quantified the shape of the skull in unprecedented detail across 354 extant and 37 extinct avian and non-avian dinosaurs. Comparative analyses reveal fundamental differences in how skull shape evolved in birds and non-avian dinosaurs. We find that the overall skull shape evolved faster in non-avian dinosaurs than in birds across all regions of the cranium. In birds, the anterior rostrum is the most rapidly evolving skull region, whereas more posterior regions—such as the parietal, squamosal, and quadrate—exhibited high rates in non-avian dinosaurs. These fast-evolving elements in dinosaurs are strongly associated with feeding biomechanics, forming the jaw joint and supporting the jaw adductor muscles. Rapid pulses of skull evolution coincide with changes to food acquisition strategies and diets, as well as the proliferation of bony skull ornaments. In contrast to the appendicular skeleton, which has been shown to evolve more rapidly in birds, avian cranial morphology is characterised by a striking deceleration in morphological evolution relative to non-avian dinosaurs. These results may be due to the reorganisation of skull structure in birds—including loss of a separate postorbital bone in adults and the emergence of new trade-offs with development and neurosensory demands. Taken together, the remarkable cranial shape diversity in birds was not a product of accelerated evolution from their non-avian relatives, despite their frequent portrayal as an icon of adaptive radiations., Using high-density morphometrics to quantify skull shape in birds and non-avian dinosaurs, this study reveals that the skull evolves at significantly slower rate in birds compared to other dinosaurs. The macroevolutionary history of the dinosaur skull reflects the mosaic functional, structural, and developmental changes in the skull across the origin of birds.

Sauropod dinosaurs include the largest terrestrial vertebrates that have ever lived. Virtually every part of the sauropod body is heavily modified in association with gigantic size and associated physiological alterations. Sauropod skulls are no exception: they feature elongated, telescoped facial regions connected to tilted neurocrania and reoriented jaw adductor muscles. Several of these cranial features have been suggested to be adaptations for feeding on the one hand and the result of paedomorphic transformation near the base of Sauropoda on the other. However, the scarcity of sauropodomorph ontogenetic series has impeded further investigation of these hypotheses. We re-evaluated the cranial material attributed to the early sauropodomorph Anchisaurus, which our phylogenetic analyses confirm to be closely related to sauropods. Digital assembly of μCT scanned skulls of the two known specimens, a juvenile and an adult, permitted us to examine the detailed ontogeny of cranial elements. The skull anatomy of Anchisaurus is distinguished by a mosaic of ancestral saurischian and sauropod-like characters. Sauropod-like characters of the braincase and adductor chamber appear late in ontogeny, suggesting that these features first evolved by the developmental mechanism of terminal addition. Shape analyses and investigation of allometric evolution demonstrate that cranial characters that appear late in the ontogeny of sauropodomorphs closely related to sauropods are already present in the embryos and juveniles of sauropods, suggesting a predisplacement-type shift in developmental timing from the ancestral anchisaurian condition. We propose that this developmental shift relaxed prior constraints on skull morphology, allowing sauropods to explore a novel range of phenotypes and enabling specializations of the feeding apparatus. The shift in timing occurred in concert with the evolution of gigantism and physiological and locomotory innovations. This article is protected by copyright. All rights reserved.

The skull of living birds is greatly modified from the condition found in their dinosaurian antecedents. Bird skulls have an enlarged, toothless premaxillary beak and an intricate kinetic system that includes a mobile palate and jaw suspensorium. The expanded avian neurocranium protects an enlarged brain and is flanked by reduced jaw adductor muscles. However, the order of appearance of these features and the nature of their earliest manifestations remain unknown. The Late Cretaceous toothed bird Ichthyornis dispar sits in a pivotal phylogenetic position outside living groups: it is close to the extant avian radiation but retains numerous ancestral characters 1-3. Although its evolutionary importance continues to be affirmed 3-8, no substantial new cranial material of I. dispar has been described beyond incomplete remains recovered in the 1870s. Jurassic and Cretaceous Lagerstatten have yielded important avialan fossils, but their skulls are typically crushed and distorted 9. Here we report four three-dimensionally preserved specimens of I. dispar- including an unusually complete skull-as well as two previously overlooked elements from the Yale Peabody Museum holotype, YPM 1450. We used these specimens to generate a nearly complete three-dimensional reconstruction of the I. dispar skull using highresolution computed tomography. Our study reveals that I. dispar had a transitional beak-small, lacking a palatal shelf and restricted to the tips of the jaws-coupled with a kinetic system similar to that of living birds. The feeding apparatus of extant birds therefore evolved earlier than previously thought and its components were functionally and developmentally coordinated. The brain was relatively modern, but the temporal region was unexpectedly dinosaurian: it retained a large adductor chamber bounded dorsally by substantial bony remnants of the ancestral reptilian upper temporal fenestra. This combination of features documents that important attributes of the avian brain and palate evolved before the reduction of jaw musculature and the full transformation of the beak.

Establishing and maintaining an institutional repository requires thoughtful and active outreach efforts to many campus constituencies. Over the past two years, librarians at Augustana College have communicated with many members of their campus community to build collaborations and collect content to fill their repository. Connie Ghinazzi, Research and Outreach librarian at Augustana College, drew on her experiences doing outreach for the Augustana Digital Commons to detail strategies that librarians can use to establish and grow their institutional repositories, including crafting a mission statement, identifying collaboration partners, acting on plans, and celebrating and reflecting on successes.

The International Standard Serial Number (ISSN) has been the standard, eight-digit code used to identify newspapers, journals, magazines, and periodicals on all kinds of media—print and electronic—for the past 40 years. Periodically, the standard must be revised to allow it to accommodate new formats, changes in the publishing industry and information supply chain, and other developments in the information field. Regina Romano Reynolds, director of the U.S. ISSN Center at the Library of Congress, describes the issues that the ISSN International Centre perceives as necessitating a revision of the standard and the likely next steps in the International Organization for Standardization standards revision process.

In 2014, Sam Houston State University Library librarians distributed a survey to students, faculty and staff to better understand how the university community was using library materials for recreational reading. The survey found that patrons had preference for print materials with a growing interest in other formats. A significant number of respondents did not view the library as a source of recreational reading materials; those who did read across a broad swath of genres. Greater understanding of patron recreational reading preferences empower the library to expand the library collection to meet all patron demands.

The avian skull is distinctive in its construction and in its function. Much of bird anatomical variety is expressed in the beak; but the beak itself, largely formed of the premaxillary bone, is set upon a shortened face and a bulbous, enlarged braincase. Here, we use original anatomical observations and reconstructions to describe the overall form of the avian skull in a larger context and to provide a general account of the evolutionary transformation from the early dinosaur skull-the skull of an archosaurian macropredator-to that of modern birds. Facial shortening, the enlargement of the braincase around an enlarged brain (with consequential reduction of circumorbital elements and the adductor chamber), and general thinning and looser articulation of bones are trends. Many of these owe to juvenilization or paedomorphosis, something that is abundantly evident from comparison of a juvenile early theropod (Coelophysis) to early avialans like Archaeopteryx Near the avian crown, the premaxilla becomes dramatically enlarged and integrated into the characteristic mobile kinetic system of birds. We posit that this addition of a large element onto the skull may be biomechanically feasible only because of the paedomorphic shortening of the face; and kinesis of the beak only because of the paedomorphic thinning of the bones and loosening of articulations, as played out in reverse during the maturation of Coelophysis Finally, the beak itself becomes elaborated as the hands are integrated into the wing. There are structural, kinematic, and neurological similarities between avian pecking and primate grasping. The ability to precision-select high-quality food against a complex but depauperate background may have permitted crown birds to survive the end-Cretaceous cataclysm by feeding on insects, seeds, and other detritus after the collapse of higher trophic levels in the food web.

Major transformations in brain size and proportions, such as the enlargement of the brain during the evolution of birds, are accompanied by profound modifications to the skull roof. However, the hypothesis of concerted evolution of shape between brain and skull roof over major phylogenetic transitions, and in particular of an ontogenetic relationship between specific regions of the brain and the skull roof, has never been formally tested. We performed 3D morphometric analyses to examine the deep history of brain and skull-roof morphology in Reptilia, focusing on changes during the well-documented transition from early reptiles through archosauromorphs, including nonavian dinosaurs, to birds. Non-avialan taxa cluster tightly together in morphospace, whereas Archaeopteryx and crown birds occupy a separate region. There is a one-to-one correspondence between the forebrain and frontal bone and the midbrain and parietal bone. Furthermore, the position of the forebrain–midbrain boundary correlates significantly with the position of the frontoparietal suture across the phylogenetic breadth of Reptilia and during the ontogeny of individual taxa. Conservation of position and identity in the skull roof is apparent, and there is no support for previous hypotheses that the avian parietal is a transformed postparietal. The correlation and apparent developmental link between regions of the brain and bony skull elements are likely to be ancestral to Tetrapoda and may be fundamental to all of Osteichthyes, coeval with the origin of the dermatocranium. Brain and skull development are intimately related across tetrapods. Here, the authors show a close relationship between brain and skull roof across evolutionary transitions and ontogenetic stages of reptiles.

In this brief tome, Schmidt and Carstens endeavor to improve subject liaison librarians’ understanding of the “complexities of technical services” by teasing out the components of technical service...

A new specimen of the theropod dinosaur Torvosaurus tanneri discovered by Elmer Riggs in 1899 in the Freezeout Hills of Wyoming and held in the Field Museum of Natural History is described. This specimen demonstrates that unreported material of this species has been present in museum collections 80 years prior to the species' scientific description and it likely represents the first non-dental material of this species to be collected. This material comprises parts of the left foot and right hand, including phalanges which were previously unknown for Torvosaurus, and substantiates the possibility that other Torvosaurus material may be undiscovered in museum collections. Its occurrence in a multitaxon quarry is consistent with other skeletal finds of Torvosaurus, all or most of which occur in association with other, more common Morrison dinosaur taxa.

Our sensory systems face a daily barrage of auditory and visual signals whose arrival times form a wide range of audiovisual asynchronies. These temporal relationships constitute an important metric for the nervous system when surmising which signals originate from common external events. Internal consistency is known to be aided by sensory adaptation: repeated exposure to consistent asynchrony brings perceived arrival times closer to simultaneity. However, given the diverse nature of our audiovisual environment, functionally useful adaptation would need to be constrained to signals that were generated together. In the current study, we investigate the role of two potential constraining factors: spatial and contextual correspondence. By employing an experimental design that allows independent control of both factors, we show that observers are able to simultaneously adapt to two opposing temporal relationships, provided they are segregated in space. No such recalibration was observed when spatial segregation was replaced by contextual stimulus features (in this case, pitch and spatial frequency). These effects provide support for dedicated asynchrony mechanisms that interact with spatially selective mechanisms early in visual and auditory sensory pathways.

As Web-enabled mobile device adoption has increased, publishers and librarians are looking to establish ways of providing access to journals to readers, wherever and however they need it. In late 2010, Nature Publishing Group (NPG) started trialing a range of access options for readers. A number of Nature journals are available for 24-hour-view-only access via the DeepDyve platform. A range of access models including monthly and annual subscriptions have been introduced for the nature.com iPhone application (app) and iPad app. NPG representative Grace Baynes reported on the early results of these experiments with new channels and pricing models, including user feedback and uptake, and views from library customers. She also addressed other emerging technologies and business models like the Flipboard app for iPad, pay-per-view licenses, and digital textbooks.

The University of Wisconsin at Stevens Point deployed a pilot program to study the viability of supplying faculty with journal content via pay-per-view in lieu of journal subscriptions. Librarians took advantage of a University of Wisconsin system pay-per-view plan with publishers Wiley and Elsevier. Journal articles were requested and delivered using modified existing interlibrary loan (ILL) software. Along with journal content, a survey was distributed to library users to measure their reaction to this manner of delivery. Users' positive reactions to the service coupled with the savings to the library prompted the adoption of this access method for a significant number of serials titles.

Evidence suggests than human time perception is likely to reflect an ensemble of recent temporal experience. For example, prolonged exposure to consistent temporal patterns can adaptively realign the perception of event order, both within and between sensory modalities (e.g. Fujisaki et al., 2004 Nat. Neurosci., 7, 773‐778). In addition, the observation that ‘a watched pot never boils’ serves to illustrate the fact that dynamic shifts in our attentional state can also produce marked distortions in our temporal estimates. In the current study we provide evidence for a hitherto unknown link between adaptation, temporal perception and our attentional state. We show that our ability to use recent sensory history as a perceptual baseline for ongoing temporal judgments is subject to striking top-down modulation via shifts in the observer’s selective attention. Specifically, attending to the temporal structure of asynchronous auditory and visual adapting stimuli generates a substantial increase in the temporal recalibration induced by these stimuli. We propose a conceptual framework accounting for our findings whereby attention modulates the perceived salience of temporal patterns. This heightened salience allows the formation of audiovisual perceptual ‘objects’, defined solely by their temporal structure. Repeated exposure to these objects induces high-level pattern adaptation effects, akin to those found in visual and auditory domains (e.g. Leopold & Bondar (2005) Fitting the Mind to the World: Adaptation and Aftereffects in High-Level Vision. Oxford University Press, Oxford, 189‐211; Schweinberger et al. (2008) Curr. Biol., 18, 684‐688).

Loma Linda University (LLU) is a small, health sciences-oriented university with a growing electronic resource collection with 5,674 e-books, over 70 databases, and more than 12,000 e-journals. In 2007, they decided to use print usage statistics compiled over several years with a goal of making sound decisions about retaining or cancelling print subscriptions and determining which subscriptions to flip from print to online only. The core title lists they developed were used to help guide the library in making decisions about weeding, maintaining print access, migrating to online, and placing bound volumes into remote storage. This presentation outlined the process used at LLU to identify core titles and explains some of the rationale behind their decisions. Some of the advantages and disadvantages in undertaking such a project are identified and a review from the practical side of the project may give some insight to other libraries considering such an endeavor.

A recent outreach project brought together the American University of Afghanistan and four world renowned US universities with branch campuses in Qatar’s Education City. Librarians in Qatar often collaborate with each other, but this unusual effort was the first time their collaboration reached across international borders to extend assistance to another country. The experience became a cultural exchange that brought together these dramatically different worlds. By utilizing technologies that make connecting and collaborating so easy these days, four librarians with backgrounds in public and technical services worked together to share their expertise, culminating in a learning visit by an AUAF library assistant to Doha. The sharing of skills and knowledge was a wonderful experience on many levels, and made a distinct difference in a part of the world that needs and wants so much to change.

Differences in transduction and transmission latencies of visual, auditory and tactile events cause corresponding differences in simple reaction time. As reaction time is usually measured in unimodal blocks, it is unclear whether such latency differences also apply when observers monitor multiple sensory channels. We investigate this by comparing reaction time when attention is focussed on a single modality, and when attention is divided between multiple modalities. Results show that tactile reaction time is unaffected by dividing attention, whilst visual and auditory reaction times are significantly and asymmetrically increased. These findings show that tactile information is processed preferentially by the nervous system under conditions of divided attention, and suggest that tactile events may be processed pre-attentively.

In the late 1960s and early 1970s, the articulation of politics and sound became explicitly marked during the civil rights transition to embryonic types of racial nationalism, black power and the novel forms of ‘citizenship’ implied therein. Music mediated and registered these critical shifts in political outlook, structural change and black collectivity. Yet, despite the power of black soundings to communicate or gesture toward a particular political sensibility, black popular music in particular remained elusive to those political workers most invested in identifying the articulations of popular sound aesthetics and the masses. Popular music, and soul culture more generally, frustrated nationalist efforts at enlisting the black masses, a failure that paradoxically reflected black nationalism’s inability to appeal to and enlist the political potential of the mass black public that it so valorised. %This article explores the political-aesthetic interface particularly as it played out in the relationship between cultural nationalism and black popular music. This relationship offers a powerful index of the correspondence and dissonance between the political intentions of nationalist political workers and the political desires of the urban masses. It is argued that both the formal attempts at producing revolutionary cultural products and the broader influence and reception that black nationalist politics had within the field of black popular culture were in significant ways less communicative of collective political will and desire than emergent popular musical formations.

The corrosion rate of electropolished 304 stainless steel surfaces (UNS S30400) is found to be lower by more than a factor of three relative to that determined previously for machined surfaces in mildly alkaline, hydrogenated water at 260 °C. This favorable result is attributed to significant changes in nanocrystallinity of the corrosion oxide layer caused by the removal of surface microstrain, which had been imparted during the machining process. In the absence of microstrain, a low-porosity, protective, corrosion layer forms that is composed of extremely small and uniformly-sized spinel oxide crystals. Application of scanning electron microscopy (FEG-SEM), X-ray diffraction and X-ray photoelectron spectroscopy (XPS) in conjunction with ion milling and target factor analyses, found the corrosion layer to consist of micrometer-size crystals of a ferrite-based spinel oxide (non-protective) over-laying nanometer-size crystals of a chromite-based spinel oxide (protective). Composition of both phases is unchanged from that previously observed on corroded, machined surfaces and is representative of solvus phases in the immiscible Fe(Fe1−nCrn)2O4 spinel binary. The smaller size (10 vs. 26 nm) and greater surface density (∼10,000 vs. 835 μm−2) of the chromite-based crystals relative to those formed on machined (i.e., cold-worked) surfaces, however, is consistent with the absence of preferred high energy nucleation sites on strain-free surfaces. Therefore, electropolishing, which removes surface microstrain induced by cold-working, represents a preferred reference surface condition.

Trace levels of soluble zinc(II) ions (30 ppb) maintained in mildly alkaline, hydrogenated water at 260 °C were found to reduce the corrosion rate of Alloy 600 (UNS N06600) by about 40% relative to a non-zinc baseline test [S.E. Ziemniak, M. Hanson, Corros. Sci., in press, doi:10.1016/j.corsci.2005.01.006 ]. Characterizations of the corrosion oxide layer via SEM/TEM and grazing incidence X-ray diffraction confirmed the presence of a chromite-rich oxide phase and recrystallized nickel. The oxide crystals had an approximate surface density of 3500 μm−2 and an average size of 11 ± 5 nm. Application of X-ray photoelectron spectroscopy with argon ion milling, followed by target factor analyses, permitted speciated composition versus depth profiles to be obtained. Numerical integration of the profiles revealed that: (1) alloy oxidation occurred non-selectively and (2) zinc(II) ions were incorporated into the chromite-rich spinel: (Zn0.55Ni0.3Fe0.15)(Fe0.25Cr0.75)2O4. Spinel stoichiometry places the trivalent ion composition in the single phase oxide region, consistent with the absence of the usual outer, ferrite-rich solvus layer. By comparison with compositions of the chromite-rich spinel obtained in the non-zinc baseline test, it is hypothesized that zinc(II) ion incorporation was controlled by the equilibrium for 0.55 Zn 2 + ( aq ) + ( Ni 0.7 Fe 0.3 ) ( Fe 0.3 Cr 0.7 ) 2 O 4 ( s ) ⇄ 0.40 Ni 2 + ( aq ) + 0.15 Fe 2 + ( aq ) + ( Zn 0.55 Ni 0.3 Fe 0.15 ) ( Fe 0.3 Cr 0.7 ) 2 O 4 ( s ) It is estimated that only 8% of the Ni(II) ions generated during non-selective oxidation of the alloy were retained as Ni(II) in the corrosion layer; the remainder either recrystallized to Ni(0) (38%) or were released to the aqueous phase (54%).

Trace levels of soluble zinc(II) ions (30 ppb) maintained in mildly alkaline, hydrogenated water at 260 °C were found to lower the corrosion rate of austenitic stainless steel (UNS S30400) by about a factor of five, relative to a non-zinc baseline test [S.E. Ziemniak, M. Hanson, Corros. Sci. 44 (2002) 2209] after 10,000 h. Characterizations of the corrosion oxide layer via grazing incidence X-ray diffraction and X-ray photoelectron spectroscopy in combination with argon ion milling and target factor analysis, revealed that miscibility gaps in two spinel binaries—Fe(Fe1−mCrm)2O4 and (Fe1−nZnn)Fe2O4—play a significant role in determining the composition and structure of the corrosion layer(s). Although compositions of the inner and outer corrosion oxide layers represent solvus phases in the Fe3O4–FeCr2O4 binary, zinc(II) ion incorporation into both phases leads to further phase separation in the outer (ferrite) layer. Recrystallization of the low zinc content ferrite solvus phase is seen to produce an extremely fine grain size (∼20 nm), which is comparable in size to grains in the inner layer and which is known to impart resistance to corrosion. Zinc(II) ion incorporation into the inner layer creates additional corrosion oxide film stabilization by further reducing the unit cell dimension via the substitution reaction 0.2 Zn 2 + ( aq ) + Fe ( Fe 0.35 Cr 0.65 ) 2 O 4 ( s ) ⇄ 0.2 Fe 2 + ( aq ) + ( Zn 0.2 Fe 0.8 ) ( Fe 0.35 Cr 0.65 ) 2 O 4 ( s ) The equilibrium constant for the substitution reaction is similar in magnitude to an estimate based on available free energies for FeCr2O4, ZnCr2O4, Fe2+(aq) and Zn2+(aq). This interpretation is consistent with the benefits of zinc treatment being concentration dependent.

The corrosion behavior of Alloy 600 (UNS N06600) is investigated in hydrogenated water at 260 °C. The corrosion kinetics are observed to be parabolic, the parabolic rate constant being determined by chemical descaling to be 0.055 mg dm −2 h −1/2 . A combination of scanning and transmission electron microscopy, supplemented by energy dispersive X-ray spectroscopy and grazing incidence X-ray diffraction, are used to identify the oxide phases present (i.e., spinel) and to characterize their morphology and thickness. Two oxide layers are identified: an outer, ferrite-rich layer and an inner, chromite-rich layer. X-ray photoelectron spectroscopy with argon ion milling and target factor analysis is applied to determine spinel stoichiometry; the inner layer is (Ni 0.7 Fe 0.3 )(Fe 0.3 Cr 0.7 ) 2 O 4 , while the outer layer is (Ni 0.9 Fe 0.1 )(Fe 0.85 Cr 0.15 ) 2 O 4 . The distribution of trivalent iron and chromium cations in the inner and outer oxide layers is essentially the same as that found previously in stainless steel corrosion oxides, thus confirming their invariant nature as solvi in the immiscible spinel binary Fe 3 O 4 –FeCr 2 O 4 (or NiFe 2 O 4 –NiCr 2 O 4 ). Although oxidation occurred non-selectively, excess quantities of nickel(II) oxide were not found. Instead, the excess nickel was accounted for as recrystallized nickel metal in the inner layer, as additional nickel ferrite in the outer layer, formed by pickup of iron ions from the aqueous phase, and by selective release to the aqueous phase.

Preparation of quaternary ammonium compounds from various tertiary amines and the (environmentally friendly) alkylating agent dimethyl carbonate (DMC) under conditions within the bounds of industrial production has been carried out. After unsuccessful attempts to catalyze and entrain the process, the reaction has been accelerated by using a 10-fold excess of alkylating agent. The recovered DMC and solvent have been recycled in up to five subsequent batches without loss of rate or yield. The expected steric hindrance effects on the rate were evidenced by comparison of the half-lives of dihydrogenatedtallowmethylamine (1 h), tributylamine (4 h), and the ester quat (7.5h). The product methyl carbonate quaternaries have been shown to be noncorrosive to 316 stainless steel for extended periods at elevated temperatures.

All of us, regardless of experience or achievement, need an occasional reaffirmation of our core knowledge and beliefs. This un-embellished narrative of a real-life reference interview reinforces the importance of persistent but polite attentiveness to the unexpressed needs of library users and, it is hoped, serves as an inspirational reminder not only of the joy and satisfaction endemic to librarianship but also of the profession's positive impact on users' lives.

The corrosion behavior of NiCrMo Alloy 625 (UNS N06625) has been characterized in a 10,000 h test conducted in hydrogenated water at 260 °C. The corrosion kinetics were observed to be parabolic, the parabolic rate constant being determined by chemical descaling to be 0.074 mg dm −2 h −1/2 . Characterizations of the corrosion oxide layer via grazing incidence X-ray diffraction and X-ray photoelectron spectroscopy in combination with argon ion milling and target factor analysis, revealed the presence of two spinel oxide phases and significant amounts of recrystallized nickel. Based on the distribution of three oxidized alloying constituents (Ni, Cr, Fe) with respect to depth and oxidation state, it was concluded that: (a) corrosion occurs in a non-selective manner, but significant amounts of nickel(II) ions are released to the water, and (b) the spinel oxides exist as a chromite-rich inner layer (Ni 0.7 Fe 0.3 )(Cr 0.8 Fe 0.2 ) 2 O 4 underneath a coarser, ferrite-rich outer layer (Ni 0.9 Fe 0.1 )(Cr 0.1 Fe 0.9 ) 2 O 4 . The trivalent cation distribution in each of these phases appears to represent a solvus in the immiscible NiCr 2 O 4 –NiFe 2 O 4 binary.

The corrosion behavior of an austenitic stainless steel (UNS S30400) has been characterized in a 10,000 h test conducted in hydrogenated, ammoniated water at 260 °C. The corrosion kinetics were observed to be parabolic, the parabolic rate constant being determined by chemical descaling to be 1.16 mg dm−2 h−1/2. X-ray photoelectron spectroscopy, in combination with argon ion milling and target factor analysis, was applied to provide an independent estimate of the rate constant that agreed with the gravimetric result. Based on the distribution of the three oxidized alloying constituents (Fe, Cr, Ni) with respect to depth and elemental state, it was found that: (a) corrosion occurs in a non-selective manner, and (b) the corrosion film consists of two spinel oxide layers––a ferrite-based outer layer (Ni0.2Fe0.8)(Fe0.95Cr0.05)2O4 on top of a chromite-based inner layer (Ni0.2Fe0.8)(Cr0.7Fe0.3)2O4. These compositions agree closely with the solvi phases created by immiscibility in the Fe3O4–FeCr2O4 binary, implying that immiscibility plays an important role in the phase separation process.

Two silicas, one with a mean pore diameter of 30 nm and the other non-porous, were coated with polymethacrylates of increasing hydrophobicity in the sequence: poly-2-hydroxyethylmethacrylate (P2HEMA)1 polyethylmethacrylate (PEMA) and poly-n-octylmethacrylate (POMA). Association constants, Kass, between lysozyme and the coated silicas were determined by means of frontal analysis, and the apparent heats of adsorption, delta Happ, by means of microcalorimetry. Using Kass and delta Happ the changes in the apparent free energy, delta Gapp, and in the apparent entropy, delta Sapp, were calculated at a concentration of lysozyme < 10 mumol/l. The association between the lysozyme and the coated silica gave negative delta Happ and delta Sapp values. The delta Sapp values calculated from the experimental data in the absence of an added electrolyte and with 0.1 M sodium perchlorate present to be -12 (-96) J/mol deg on the P2HEMA silica, -27 (-51) J/mol deg on the PEMA silica, -98 (-186) J/mol deg on the POMA silica, respectively. The high delta Sapp value of the lysozyme on the POMA silica reflects a kind of stabilisation effect due to the conformational changes of lysozyme on the most hydrophobic POMA silica. As evidenced by RPC, lysozyme elutes on the POMA column in its totally unfolded form enabling a more disordered conformation with respect to entropy than in the native form.