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Elevated pulmonary vascular resistance (PVR) is broadly accepted as an imminent risk factor for mortality after heart transplantation (HTx). However, no current HTx recipient risk score includes PVR or other hemodynamic parameters. This study examined the utility of various hemodynamic parameters for risk stratification in a contemporary HTx population.Patients from seven German HTx centers undergoing HTx between 2011 and 2015 were included retrospectively. Established risk factors and complete hemodynamic datasets before HTx were analyzed. Outcome measures were overall all-cause mortality, 12-month mortality, and right heart failure (RHF) after HTx.The final analysis included 333 patients (28% female) with a median age of 54 (IQR 46-60) years. The median mean pulmonary artery pressure was 30 (IQR 23-38) mm Hg, transpulmonary gradient 8 (IQR 5-10) mm Hg, and PVR 2.1 (IQR 1.5-2.9) Wood units. Overall mortality was 35.7%, 12-month mortality was 23.7%, and the incidence of early RHF was 22.8%, which was significantly associated with overall mortality (log-rank HR 4.11, 95% CI 2.47-6.84; log-rank p.0001). Pulmonary arterial elastance (Ea) was associated with overall mortality (HR 1.74, 95% CI 1.25-2.30; p.001) independent of other non-hemodynamic risk factors. Ea values below a calculated cutoff represented a significantly reduced mortality risk (HR 0.38, 95% CI 0.19-0.76; p.0001). PVR with the established cutoff of 3.0 WU was not significant. Ea was also significantly associated with 12-month mortality and RHF.Ea showed a strong impact on post-transplant mortality and RHF and should become part of the routine hemodynamic evaluation in HTx candidates.

The present study was designed to investigate the dynamics of right atrial pressure (RAP) and mid-regional pro-atrial natriuretic peptide (MR-proANP) during physical exercise in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and to determine whether these parameters might serve as a tool to measure exercise-dependent atrial stress as an indicator of right heart failure.This prospective observational cohort study included 100 CTEPH patients who underwent right heart catheterization during physical exercise (eRHC). Blood samples for MR-proANP measurement were taken prior, during, and after eRHC. MR-proANP levels were correlated to RAP levels at rest, at peak exercise (eRAP), and during recovery. RAP at rest ≤7 mmHg was defined as normal and eRAP15 mmHg as suggestive of right heart failure.During eRHC mean RAP increased from 6 mmHg (standard deviation, SD 4) to 16 mmHg (SD 7; p0.001). MR-proANP levels and dynamics correlated with RAP at rest (rRAP and MR-proANP dynamics unmask manifest and latent right heart failure in CTEPH patients.

CO, ethylene, and H2 demonstrate divergent adsorption enthalpies upon interaction with a series of anion-exchanged Ni2X2BTDD materials (X = OH, F, Cl, Br; H2BTDD = bis(1H-1,2,3-triazolo[4,5-b][4',5'-i])dibenzo[1,4]dioxin)). The dissimilar responses of these conventional π-acceptor gaseous ligands are in contrast with the typical behavior that may be expected for gas sorption in metal-organic frameworks (MOFs), which generally follows similar periodic trends for a given set of systematic changes to the host MOF structure. A combination of computational and spectroscopic data reveals that the divergent behavior, especially between CO and ethylene, stems from a predominantly σ-donor interaction between the former and Ni2+ and a π-acceptor interaction for the latter. These findings will facilitate further deliberate postsynthetic modifications of MOFs with open metal sites to control the equilibrium selectivity of gas sorption.

Background The dwarf cuttlefish Sepia bandensis, a camouflaging cephalopod from the Indo-Pacific, is a promising new model organism for neuroscience, developmental biology, and evolutionary studies. Cuttlefish dynamically camouflage to their surroundings by altering the color, pattern, and texture of their skin. The skin's "pixels" (chromatophores) are controlled by motor neurons projecting from the brain. Thus, camouflage is a visible representation of neural activity. In addition to camouflage, the dwarf cuttlefish uses dynamic skin patterns for social communication. Despite more than 500 million years of evolutionary separation, cuttlefish and vertebrates converged to form limbs, camera-type eyes and a closed circulatory system. Moreover, cuttlefish have a striking ability to regenerate their limbs. Interrogation of these unique biological features will benefit from the development of a new set of tools. Dwarf cuttlefish reach sexual maturity in 4 months, they lay dozens of eggs over their 9-month lifespan, and the embryos develop to hatching in 1 month. Results Here, we describe methods to culture dwarf cuttlefish embryos in vitro and define 25 stages of cuttlefish development. Conclusion This staging series serves as a foundation for future technologies that can be used to address a myriad of developmental, neurobiological, and evolutionary questions.

Heterogeneous carbon nitrides have numerous advantages as photocatalysts, including strong light absorption, tunable band edges, and scalability, but their performance and continued development are limited by fast charge recombination and an under-developed mechanistic understanding of photodriven interfacial electron transfer. These shortcomings are a result of complex photophysics, leading to rate asynchrony between oxidation and reduction, as well as redox processes driven out of electronic trap states rather than excited states. We show that a well-defined triplet excited state in cyanamide-modified carbon nitride is realized with appropriately sized particles. The utility of this long-lived excited state is demonstrated by its ability to drive a hydroamidation photoredox cycle. By the tuning of the particle size of CNx, the oxidation-reduction photochemistry of carbon nitride may be balanced to achieve a redox-neutral closed photocatalytic cycle. These results uncover a triplet excited state chemistry for appropriately sized CNx particles that preludes a rich energy and electron transfer photochemistry for these materials.

Adam J. Rieth is a postdoctoral scholar in the Nocera group at Harvard University. He completed his undergraduate studies at the University of North Carolina at Chapel Hill, in his hometown. He then earned his Ph.D. in the laboratory of Prof. Mircea Dinca at the Massachusetts Institute of Technology, where he designed metal-organic frameworks for water harvesting. For the past year in the Nocera group, he has investigated the mechanisms and kinetics of photochemical processes that activate strong bonds. Daniel G. Nocera is the Patterson Rockwood Professor of Energy at Harvard University. He created the field of proton-coupled electron transfer (PCET) at a mechanistic level with the first kinetics measurements and theory of PCET. From this platform, he invented the Artificial Leaf and Bionic Leaf for the solar-driven fixation of carbon dioxide from air in the form of biomass and liquid fuels at energy efficiencies that are 10× greater than natural photosynthesis. He has since elaborated the Bionic Leaf for the solar-driven fixation of nitrogen from air for distributed and carbon-negative ammonia (and fertilizer) synthesis.

The treatment of patients with advanced heart failure requires interdisciplinary care in a qualified heart failure team, especially prior to and in the follow-up of mechanical circulatory support (MCS) implantation and heart transplantation (HTx). The basic prerequisite is the early specialized evaluation of symptomatic patients even under optimized heart failure treatment. Diagnostics and treatment are initially aimed at improving the prognosis. If the prerequisites for MCS or HTx treatment are present, possible contraindications and problems have to be evaluated in order to achieve an optimal risk-benefit ratio for the abovementioned complex treatments with limited resources. The optimal treatment is still HTx if the conditions are right, so this should be sought in all potential patients. At the same time, the optimal individual transplantation window should not be missed. The provision of a MCS system is a treatment performed with very good results for patients with exclusion criteria for HTx or with hemodynamic instability that prevents a longer waiting time for a donor organ. Short-term and medium-term survival is now comparable to HTx when carefully indicated. Timely implantation before the onset of manifest end-organ damage is crucial. Optimized implementation of advanced treatment requires professional structures that enable effective interdisciplinary cooperation between different sectors of health care.Die Behandlung von Patienten mit fortgeschrittener Herzinsuffizienz erfordert eine interdisziplinäre Betreuung in einem qualifizierten Herzinsuffizienzteam, insbesondere im Vorfeld und in der Nachbetreuung der Versorgung mit einem mechanischen Kreislaufunterstützungssystem (MCS) und einer Herztransplantation (HTx). Grundvoraussetzung ist die frühzeitige spezialisierte Evaluation symptomatischer Patienten auch unter optimierter Herzinsuffizienzbehandlung. Die Diagnostik und Therapie ist zunächst auf eine Prognoseverbesserung ausgerichtet. Liegen die Voraussetzungen für eine MCS- oder HTx-Therapie vor, so sind mögliche Kontraindikationen und Probleme zu evaluieren, um eine optimale Nutzen-Risiko-Relation für die genannten aufwendigen Therapien mit begrenzten Ressourcen zu erzielen. Die optimale Therapie besteht bei entsprechenden Voraussetzungen nach wie vor in der HTx, sodass diese bei allen potenziellen Patienten angestrebt werden sollte. Dabei darf das optimale, individuelle Transplantationsfenster nicht verpasst werden. Die Versorgung mit einem MCS-System ist eine mit sehr guten Ergebnissen durchgeführte Therapie für Patienten mit Ausschlusskriterien für eine HTx oder mit einer hämodynamischen Instabilität, die eine längere Wartezeit auf ein Spenderorgan verhindert. Das kurz- und mittelfristige Überleben ist bei sorgfältiger Indikationsstellung mittlerweile vergleichbar mit dem nach HTx. Entscheidend ist die rechtzeitige Implantation vor dem Auftreten von manifesten Endorganschäden. Für die optimierte Umsetzung erweiterter Therapien bedarf es professioneller Strukturen, die eine effektive interdisziplinäre Kooperation unterschiedlicher Sektoren der Gesundheitsversorgung ermöglichen.

SummaryThe coleoid cephalopods (cuttlefish, octopus, and squid) are a group of soft-bodied marine mollusks that exhibit an array of interesting biological phenomena, including dynamic camouflage, complex social behaviors, prehensile regenerating arms, and large brains capable of learning, memory, and problem-solving [1–10]. The dwarf cuttlefish,Sepia bandensis, is a promising model cephalopod species due to its small size, substantial egg production, short generation time, and dynamic social and camouflage behaviors [11]. Cuttlefish dynamically camouflage to their surroundings by changing the color, pattern and texture of their skin. Camouflage is optically-driven, and is achieved by expanding and contracting hundreds of thousands of pigment-filled saccules (chromatophores) in the skin, which are controlled by motor neurons emanating from the brain. We generated a dwarf cuttlefish brain atlas using magnetic resonance imaging (MRI), deep learning, and histology, and we built an interactive web tool (cuttlebase.org) to host the data. Guided by observations in other cephalopods [12–20], we identified 32 brain lobes, including two large optic lobes (75% the total volume of the brain), chromatophore lobes whose motor neurons directly innervate the chromatophores of the color-changing skin, and a vertical lobe that has been implicated in learning and memory. This brain atlas provides a valuable tool for exploring the neural basis of cuttlefish behavior.

CO, ethylene, and H

RuNi nanoparticles supported on a metal-organic framework (RuNi@MOF) and formed in situ from a ruthenium complex enclosed inside a nickel-based MOF act as a highly active catalyst for the Guerbet reaction of ethanol to 1-butanol, providing turnover numbers up to 725 000 Ru

Metal–organic frameworks (MOFs) have diverse applications involving the storage, separation and sensing of weakly interacting, high-purity gases. Exposure to impure gas streams and interactions with corrosive and coordinating gases raises the question of chemical robustness; however, the factors that determine the stability of MOFs are not fully understood. Framework materials have been previously categorized as either thermodynamically or kinetically stable, but recent work has elucidated an energetic penalty for porosity for all these materials with respect to a dense phase, which has implications for the design of materials for gas storage, heterogeneous catalysis and electronic applications. In this Review, we focus on two main strategies for stabilization of the porous phase — using inert metal ions or increasing the heterolytic metal–ligand bond strength. We review the progress in designing robust materials for the capture of coordinating and corrosive gases such as H2O vapour, NH3, H2S, SO2, nitrogen oxides (NOx) and elemental halogens. We envision that the pursuit of strategies for kinetic stabilization of MOFs will yield increasing numbers of robust frameworks suited to harsh conditions and that short-term stability towards these challenging gases will be predictive of long-term stability for applications in less demanding environments., National Science Foundation (Grant DMR-1452612)

Super-reducing excited states have the potential to activate strong bonds, leading to unprecedented photoreactivity. Excited states of radical anions, accessed via reduction of a precatalyst followed by light absorption, have been proposed to drive photoredox transformations under super-reducing conditions. Here we investigate the radical anion of naphthalene monoimide as a photoreductant and find that the radical doublet excited state has a lifetime of 24 ps, which is too short to facilitate photoredox activity. To account for the apparent photoreactivity of the radical anion, we identify an emissive two-electron reduced Meisenheimer complex of naphthalene monoimide, [NMI(H)]–. The singlet excited state of [NMI(H)]– is a potent reductant (–3.08 V vs Fc/Fc+), is long-lived (20 ns), and its emission can be dynamically quenched by chloroarenes to drive a radical photochemistry, establishing that it is this emissive excited state that is competent for reported C–C and C–P coupling reactivity. These results provide a mechanistic basis for photoreactivity at highly reducing potentials via singlet excited state manifolds and lays out a clear path for the development of exceptionally reducing photoreagents derived from electron-rich closed-shell anions.

Nickel-catalysed aryl amination and etherification are driven with sunlight using a surface-modified carbon nitride to extend the absorption of the photocatalyst into a wide range of the visible region. In contrast to traditional homogeneous photochemical methodologies, the lower cost and higher recyclability of the metal-free photocatalyst, along with the use of readily available sunlight, provides an efficient and sustainable approach to promote nickel-catalysed cross-couplings., Nickel-catalysed aryl amination and etherification are driven with sunlight using a surface-modified carbon nitride to extend the absorption of the photocatalyst such that they may be driven with solar light.

The ability to control the relative humidity at which water uptake occurs in a given adsorbent is advantageous, making that material applicable to a variety of different applications. Here, we show that cation exchange in a metal-organic framework allows precise control over the humidity onset of the water uptake step. Controlled incorporation of cobalt in place of zinc produces open metal sites into the cubic triazolate framework MFU-4l, and thereby provides access to materials with uptake steps over a 30% relative humidity range. Notably, the MFU-4l framework has an extremely high water adsorption capacity of 1.05 g g-1, amongst the highest known for porous materials. The total water capacity is independent of the cobalt loading, showing that cation exchange is a viable route to increase the hydrophilicity of metal-organic frameworks without sacrificing capacity.

The reversible capture of water vapor at low humidity can enable transformative applications such as atmospheric water harvesting and heat transfer that uses water as a refrigerant, replacing environmentally detrimental hydro- and chloro-fluorocarbons. The driving force for these applications is governed by the relative humidity at which the pores of a porous material fill with water. Here, we demonstrate modulation of the onset of pore-filling in a family of metal–organic frameworks with record water sorption capacities by employing anion exchange. Unexpectedly, the replacement of the structural bridging Cl– with the more hydrophilic anions F– and OH– does not induce pore-filling at lower relative humidity, whereas the introduction of the larger Br– results in a substantial shift toward lower relative humidity. We rationalize these results in terms of pore size modifications as well as the water hydrogen bonding structure based on detailed infrared spectroscopic measurements. Fundamentally, our data suggest that, in the presence of strong nucleation sites, the thermodynamic favorability of water pore-filling depends more strongly on the pore diameter and the interface between water in the center of the pore and water bound to the pore walls than the hydrophilicity of the pore wall itself. On the basis of these results, we report two materials that exhibit record water uptake capacities in their respective humidity regions and extended stability over 400 water adsorption–desorption cycles., National Science Foundation (Grant DMR-1452612)

Water in confinement exhibits properties significantly different from bulk water due to frustration in the hydrogen-bond network induced by interactions with the substrate. Here, we combine infrared spectroscopy and advanced molecular dynamics simulations to probe the structure of confined water as a function of relative humidity within a metal-organic framework containing cylindrical pores lined with an ordered array of cobalt open coordination sites. Building upon the quantitative agreement between experimental and theoretical spectra, we demonstrate that water at low relative humidity initially binds to the open metal sites and subsequently forms disconnected one-dimensional chains of hydrogen-bonded water molecules bridging between the cobalt sites. Upon further increase in relative humidity, these water chains nucleate pore filling, with water molecules occupying the entire pore interior before the relative humidity reaches 30%. Systematic analysis of the rotational and translational dynamics indicates heterogeneity in this pore-confined water, with water molecules displaying distinct levels of mobility as a function of the distance from the pore surface.

A series of new mesoporous metal-organic frameworks (MOFs) made from extended bisbenzenetriazolate linkers exhibit coordinatively unsaturated metal sites that are responsible for high and reversible uptake of ammonia. Isostructural Mn, Co, and Ni materials adsorb 15.47, 12.00, and 12.02 mmol of NH3/g, respectively, at STP. Importantly, these near-record capacities are reversible for at least three cycles. These results demonstrate that azolate MOFs are sufficiently thermally and chemically stable to find uses in recyclable sorption, storage, and potentially separation of chemically challenging and/or corrosive gases, especially when designed to exhibit a high density of open metal sites.

In a recent issue of Chem, Towsif Abtab et al. describe a Cr3+-based metal-organic framework (MOF) that can capture a record-shattering 200% of its weight in water. Remarkably, whereas the Fe3+ and Al3+ variants of the framework collapse upon water exposure, the Cr3+ version shows no decline in crystallinity or capacity after 100 cycles of water uptake. Synthesized via a cation exchange process of Cr2+ for Fe3+, the achievement of the highly porous Cr3+ structure points the way toward additional MOF topologies with exceptional stability enabled by inert metals.

In a recent issue of Science , Kim et al. describe a device that captures water vapor from the atmosphere at low relative humidity by using a metal-organic framework as the active sorbent. This first-of-its-kind water harvester can be powered by only solar thermal energy.

Rising global standards of living coupled to the recent agreement to eliminate hydrofluorocarbon refrigerants are creating intense pressure to develop more sustainable climate control systems. In this vein, the use of water as the refrigerant in adsorption heat pumps is highly attractive, but such adsorption systems are constrained to large size and poor efficiency by the characteristics of currently employed water sorbents. Here we demonstrate control of the relative humidity of water uptake by modulating the pore size in a family of isoreticular triazolate metal–organic frameworks. Using this method, we identify a pair of materials with stepped, nonoverlapping water isotherms that can function in tandem to provide continuous cooling with a record ideal coefficient of performance of 1.63. Additionally, when used in a single-stage heat pump, the microporous Ni2Cl2BBTA has the largest working capacity of any material capable of generating a 25 °C difference between ambient and chiller output.

Ammonia is a vital commodity in our food supply chain, but its toxicity and corrosiveness require advanced protection and mitigation. These needs are not met efficiently by current materials, which suffer from either low capacity or low affinity for NH3. Here, we report that a series of microporous triazolate metal–organic frameworks containing open metal sites exhibit record static and dynamic ammonia capacities. Under equilibrium conditions at 1 bar, the materials adsorb up to 19.79 mmol NH3 g–1, more than twice the capacity of activated carbon, the industry standard. Under conditions relevant to personal protection equipment, capacities reach 8.56 mmol g–1, 27% greater than the previous best material. Structure–function relationships and kinetic analyses of NH3 uptake in isostructural micro- and mesoporous materials made from Co, Ni, and Cu reveal stability trends that are in line with the water substitution rates in simple metal–aquo complexes. Altogether, these results provide clear, intuitive descri...

The mechanism of proton conductivity in porous solids (i.e., Grotthuss or vehicular) is related to the structure and chemical environment of the pores. Direct observation of structure–function relationships is difficult because state-of-the-art solid proton conductors are often amorphous. Here, we present a systematic elucidation of two distinct proton transport pathways within MIT-25, a mesoporous metal–organic framework that exhibits parallel channels of ∼27 A and ∼4.5 A width. We characterize transport through these pores using temperature- and humidity-dependent proton conductivity measurements and density functional theory. Through control of vapor pressure we are able to sequentially fill the small and large pores, promoting proton conductivity with distinct activation energies at low and high relative humidity, respectively.

TiO2 is an exemplary semiconductor anode material for photoelectrochemical (PEC) water-splitting electrodes due to its functionality, long-term stability in corrosive environments, nontoxicity, and low cost. In this study, TiO2 photoanodes with enhanced photocurrent density were synthesized by atomic layer deposition (ALD) of TiO2 onto a porous, transparent, and conductive fluorine-doped tin oxide nanoparticle (nanoFTO) scaffold fabricated by solution processing. The simplicity and disordered nature of the nanoFTO nanostructure combined with the ultrathin conformal ALD TiO2 coatings offers advantages including decoupling charge carrier diffusion length from optical penetration depth, increased photon absorption probability through scattering, complimentary photon absorption, and favorable interfaces for charge separation and transfer across the various junctions. We examine the effects of porosity of the nanoFTO scaffold and thickness of the TiO2 coating on PEC performance and achieve an optimal photocurrent of 0.7 mA cm(-2) at 0 V vs. Ag/AgCl under 100 mW cm(-2) AM 1.5 G irradiation in a 1 M KOH aqueous electrolyte. Furthermore, the fundamental mechanisms behind the improvements are characterized via cyclic voltammetry, incident photon-to-current efficiency, transient photocurrent spectroscopy, and electrochemical impedance spectroscopy and are contrasted with those of single crystal rutile TiO2 nanowires. The strategies employed in this work highlight the opportunities inherent to these types of heteronanostructures, where the lessons may be applied to improve the PEC conversion efficiencies of other promising semiconductors, such as hematite (α-Fe2O3) and other materials more sensitive to visible light.

Molecular catalysts offer tremendous advantages for stereoselective polymerization because their activity and selectivity can be optimized and understood mechanistically using the familiar tools of organometallic chemistry. Yet, this exquisite control over selectivity comes at an operational price that is generally not justifiable for the large-scale manufacture of polyfolefins. In this report, we identify Co-MFU-4l, prepared by cation exchange in a metal-organic framework, as a solid catalyst for the polymerization of 1,3-butadiene with high stereoselectivity (99% 1,4-cis). To our knowledge, this is the highest stereoselectivity achieved with a heterogeneous catalyst for this transformation. The polymer's low polydispersity (PDI ≈ 2) and the catalyst's ready recovery and low leaching indicate that our material is a structurally resilient single-site heterogeneous catalyst. Further characterization of Co-MFU-4l by X-ray absorption spectroscopy provided evidence for discrete, tris-pyrazolylborate-like coordination of Co(II). With this information, we identify a soluble cobalt complex that mimics the structure and reactivity of Co-MFU-4l, thus providing a well-defined platform for studying the catalytic mechanism in the solution phase. This work underscores the capacity for small molecule-like tunability and mechanistic tractability available to transition metal catalysis in metal-organic frameworks.

The capture of water vapor at low relative humidity is desirable for producing potable water in desert regions and for heat transfer and storage. Here, we report a mesoporous metal–organic framework that captures 82% water by weight below 30% relative humidity. Under simulated desert conditions, the sorbent would deliver 0.82 gH2O gMOF–1, nearly double the quantity of fresh water compared to the previous best material. The material further demonstrates a cooling capacity of 400 kWh m–3 per cycle, also a record value for a sorbent capable of creating a 20 °C difference between ambient and output temperature. The water uptake in this sorbent is optimized: the pore diameter of our material is above the critical diameter for water capillary action, enabling water uptake at the limit of reversibility., A mesoporous metal−organic framework exhibits record uptake of water at low humidity, of importance in fresh water generation and heat pumps.

The surface of pores in covalent organic networks was chemically modified for better ammonia capture.

This observational study examined changes in teachers' instruction and student outcomes in response to a 3-year-long professional development collaboration between university researchers and a middle-school language arts team. Professional development supported teachers in implementing multimedia anchored instruction, a video-based instructional method shown to be effective for diverse learners. The Integrated Curriculum Project (ICP-3) used multimedia anchored instruction to promote constructivist reform and infuse technology into an integrated social studies and language arts curriculum to improve literacy and critical thinking skills for at-risk adolescents, including students with disabilities and those from culturally and linguistically diverse backgrounds. Findings revealed that teachers moved toward a more learner-centered instructional approach and that both teachers and students made significant changes in classroom behaviors, including the quantity and quality of questions and time spent in small-group discussion. Implications for research and practice regarding sustained, collaborative professional development in technology integration, in this case, using multimedia anchored instruction, are presented. © 2012 Wiley Periodicals, Inc.

More than 20 years have passed since the Cognition and Technology Group at Vanderbilt University first conceptualized and began to explore how to effectively operationalize cognitive learning theory in applied instructional settings, innovatively infusing their model with emerging technologies. Yet, to date a comprehensive review of findings on the multimedia anchored instruction (MAI) model has not been conducted. This synthesis of the literature isolates a small segment of that literature: intervention studies in which MAI was implemented with preservice teachers to increase knowledge, support revisions of beliefs discordant with effective teaching practice, develop skills, and foster transfer. Findings revealed that MAI is an effective service delivery model for meeting these preservice teacher education goals.

Deficiencies of acetabular bone stock at revision hip replacement were reconstructed with two different types of allograft using impaction bone grafting and a Burch-Schneider reinforcement ring. We compared a standard frozen non-irradiated bone bank allograft (group A) with a freeze-dried irradiated bone allograft, vitalised with autologous marrow (group B). We studied 78 patients (79 hips), of whom 87% (69 hips) had type III acetabular defects according to the American Academy of Orthopaedic Surgeons classification at a mean of 31.4 months (14 to 51) after surgery. At the latest follow-up, the mean Harris hip score was 69.9 points (13.5 to 97.1) in group A and 71.0 points (11.5 to 96.5) in group B. Each hip showed evidence of trabeculation and incorporation of the allograft with no acetabular loosening.These results suggest that the use of an acetabular reinforcement ring and a living composite of sterile allograft and autologous marrow appears to be a method of reconstructing acetabular deficiencies which gives comparable results to current forms of treatment.

A large, segmented neutron detector array, the “neutron wall”, has been constructed for use with the TwinSol radioactive nuclear beam facility at the University of Notre Dame. At present, the array consists of 16 position-sensitive plastic scintillator bars. The position and energy resolution of the array, and its neutron-detection efficiency are described.

This study employed classroom observations and teacher and student interviews to examine the impact of anchored instruction on student and teacher behaviors in two inclusive ninth-grade language arts classes. Specifically, the investigators examined the effect of anchored instruction on (a) the length (long or short) and level (factual or interpretive) of questions asked by, and responses to student questions by, the classroom teacher; (b) the length and level of questions asked by, and responses made by, ninth-grade students; and (c) student participation in classroom instructional activities. Overall, the results of this study supported the use of anchored instruction as a promising intervention for high school students with high-incidence disabilities. The results indicated that as teachers increased the level and length of their questions, students reciprocated by providing higher level and longer responses to questions and asked longer and higher level questions. Students were observed to be more actively involved in classroom instructional activities, and they increased their school attendance. The data collected in this study support the idea that technology combined with effective instruction can yield positive results for students and teachers. However, although the data are promising, they are preliminary. They underscore the importance of conducting additional research examining the impact of anchored instruction and its component parts on the academic outcomes attained by middle and high school students with high-incidence disabilities.

Interfacial electron transfer to and from conductive Sn-doped In2O3 (ITO) nanoparticles (NPs) in mesoporous thin films has been investigated by transient absorption measurements using surface-bound [Ru(II)(bpy)2(dcb)](2+) (bpy is 2,2'-bipyridyl and dcb is 4,4'-(COOH)2-2,2'-bipyridyl). Metal-to-ligand charge transfer excitation in 0.1 M LiClO4 MeCN results in efficient electron injection into the ITO NPs on the picosecond time scale followed by back electron transfer on the nanosecond time scale. Rates of back electron transfer are dependent on thermal annealing conditions with the rate constant increasing from 1.8 × 10(8) s(-1) for oxidizing annealing conditions to 8.0 × 10(8) s(-1) for reducing conditions, presumably due to an enhanced electron concentration in the latter.

Electrocatalytic water oxidation occurs at fluoride-doped tin oxide (FTO) electrodes that have been surface-modified by addition of Co(II). On the basis of X-ray photoelectron spectroscopy and transmission electron microscopy measurements, the active surface site appears to be a single site or small-molecule assembly bound as Co(II), with no evidence for cobalt oxide film or cluster formation. On the basis of cyclic voltammetry measurements, surface-bound Co(II) undergoes a pH-dependent 1e(-)/1H(+) oxidation to Co(III), which is followed by pH-dependent catalytic water oxidation. O2 reduction at FTO occurs at -0.33 V vs NHE, allowing for in situ detection of oxygen as it is formed by water oxidation on the surface. Controlled-potential electrolysis at 1.61 V vs NHE at pH 7.2 resulted in sustained water oxidation catalysis at a current density of 0.16 mA/cm(2) with 29,000 turnovers per site over an electrolysis period of 2 h. The turnover frequency for oxygen production per Co site was 4 s(-1) at an overpotential of 800 mV at pH 7.2. Initial experiments with Co(II) on a mesoporous, high-surface-area nanoFTO electrode increased the current density by a factor of ~5.

The Analysis of Technology Assistance for Children (ATAC) project was undertaken in recognition of the severe limit in information on current practices in field applications of assistive technology. Specifically, the ATAC project focused on investigating three problem areas: (1) the status of assistive technology in educational and related settings with school-age children with disabilities; (2) the benefits and barriers associated with using assistive technology for these youngsters; and (3) the effects of assistive technology use. A major aspect of the project involved a general survey of assistive technology use in special education classrooms across three states: Indiana, Kentucky, and Tennessee. This article presents the results of this effort, and discusses the implications in regard to improving practices in the field.

To increase the information available about the efficacy of strategies to train special education teachers to use technology, a study was conducted to describe the changes in teacher and student behavior that accompanied: (a) the placement of a computer in special education classrooms and (b) the completion of a 4-month practicum to integrate the computer into instructional programs. This research was conducted in concert with a master's degree program designed to train teachers of students with mild handicaps to effectively integrate technology into their instructional programs. This study employed a within-subjects (Intervention phase x Subjects) design to examine changes in individual classroom environments, and teacher's perceptions and beliefs across phases of intervention. This design allowed the statistical analysis of changes in classroom, student, and teacher variables across two intervention phases as measured by a computer-use attitudinal survey and a structured interview. The most striking change found across the three phases of this study was the teachers' perception of the computer's role in their instructional program. Initially, teachers viewed the computer as a motivational and reinforcement device that had some utility in providing drill on content previously presented by the teacher. After completing the computer integration practicum course, the teachers maintained their initial perception of the computer as a powerful tool for motivating and reinforcing students and providing drill and practice, but began to view the computer as a useful tool for themselves and for their students.