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We describe the design, testing, and performance of an actively controlled deep-sea Free Ocean CO 2 Enrichment (dp-FOCE) system for the execution of seafloor experiments relating to the impacts of ocean acidification on natural ecosystems. We used the 880 m deep MARS (Monterey Accelerated Research System) cable site offshore Monterey Bay, California for this work, but the Free Ocean CO 2 Enrichment (FOCE) system concept is designed to be scalable and can be modified to be used in a wide variety of ocean depths and locations. The main frame is based on a flume design with active thruster control of flow and a central experimental chamber. The unit was allowed to free fall to the seafloor and connected to the cable node by remotely operated vehicle (ROV) manipulation. For operation at depth we designed a liquid CO 2 containment reservoir which provided the CO 2 enriched working fluid as ambient seawater was drawn through the reservoir beneath the more buoyant liquid CO 2 . Our design allowed for the significant lag time associated with the hydration of the dissolved CO 2 molecule, resulting in an e-folding time, τ , of 97 s between fluid injection and pH sensing at the mean local T =4.31±0.14 °C and pH T of 7.625±0.011. The system maintained a pH offset of ~0.4 pH units compared to the surrounding ocean for a period of ~1 month. The unit allows for the emplacement of deep-sea animals for testing. We describe the components and software used for system operation and show examples of each. The demonstrated ability for active control of experimental systems opens new possibilities for deep-sea biogeochemical perturbation experiments of several kinds and our developments in open source control systems software and hardware described here are applicable to this end.

What are the most productive institutions and who are the most prolific individual scholars conducting educational psychology research? What are the topics of primary interest to educational psychologists? These were the questions that guided this study, which was a follow-up to our previous investigation of faculty productivity for the period from 1991–1996. Publications in five educational psychology journals were examined. The University of Maryland retained its top ranking for productivity in educational psychology. Richard Mayer of the University of California-Santa Barbara was the most-published educational psychologist for the most recent period, as well as for the entire period (1991–2001). Reading research remains the most popular focus for educational psychology research followed by motivation.

A shutter mechanism for reducing the effects of biofouling on bio-optical instruments deployed on oceanographic moorings has been designed, built, and tested. The initial development was carried out on a spectroradiometer. The optics of the spectroradiometer are protected by copper shutters that rotate out of the field of view prior to a measurement and rotate back after the measurement is completed. The shutter system can sense an obstruction and, if one is detected, attempt to rotate in the opposite direction. The controlling software stores the home position in the memory so the shutter can return to cover the optics, irrespective of direction of rotation. The system has been tested in the equatorial Pacific, where it has provided five months of data that are unaffected by biofouling.

The Free Ocean CO2 Enrichment (FOCE) concept and systems have been developed by the Monterey Bay Aquarium Research Institute (MBARI) as a way of performing comprehensive in situ ocean acidification (OA) seafloor experiments. MBARI funded an early project to test potential technologies for closed loop control of shifting pH associated with addition of acidified sea water, into a natural flow, stream that would manage the considerable lag times associated with the chemical reactions taking place; thus the protoFOCE was born. Later the full-scale deep water (850m depth) FOCE (dpFOCE) was tested with cabled control. We briefly outline the basic issues with OA experiments and describe why systems like FOCE are needed to better understand the impacts of OA. Early OA studies focused directly on the decreasing ability of some animals to form calcium carbonate shells under more acidic conditions. More recent work has focused on behavioral changes in marine species associated with a high CO2 environment. Each of these science studies can now be addressed by controlled in situ field experiments. Early engineering tests were published and soon external interest in the concept heightened. MBARI transferred FOCE technology to researcher working on the Great Barrier Reef. The resulting collaboration created the Coral-Prototype FOCE (cpFOCE) system. cpFOCE directly demonstrated the significant carbonate losses that may be anticipated in our “High CO2 Ocean” future. We also have the European FOCE (eFOCE), a proposal for Antarctic FOCE (antFOCE), and MBARI's own shallow water FOCE (swFOCE) with local collaborators underway. Interest in FOCE systems continues to grow as we've published and presented this capable in situ technology. To support the interested community MBARI engineering and science has developed a new concept. xFOCE is a project to create a generic FOCE reference design and to build the community support structure enabling FOCE technology to be freely available to the OA science community outside of MBARI. Within this paper we outline the technologies behind the xFOCE project and discuss the various elements of the project including decisions and ultimate goals. We also review how xFOCE can be implemented using alternate technologies if the science user chooses to do so. We outline our heavy focus on building a user group of researchers who ultimately will create and direct FOCE projects much the same as the open source software community has done with the GNU General Public License project. The distinction between “open source” and “free” is clearly articulated and we explain why this is important for building an enduring community with common standards for the execution of FOCE experiments.

Digital Windows allow real people in the real world to interact with virtual objects in a virtual world through a direct relationship between real-space and digital-space. Actions in the real world are affected by re-actions in the virtual world. As a Master's thesis Project, the scope of Digital Windows is that of a prototype for a larger vision. This vision suggests the potential for Digital Windows to be a group of input/output nodes (located in separate, yet related places) that allow physically distant by-passers to interact with each other. It will take a pause at a node to see it as more than something hanging on a wall; and, several pauses to understand the interaction with people at the other nodes. This, in essence, becomes a progressive discovery with each by-pass that results in a pause. Environmental psychology might associate this process of discovery with arousal (physiological reactions). Arousal fluctuates directly with the complexity of what is going on. One way to keep things simple for bypassers is to treat them as by-passers, and require nothing of them. As windows allow us to see specific parts of other places; the content of this project is a virtual space ‘between' some real spaces. The real spaces at each node have unique points-of-view into the shared virtual space, through respective digital windows. Objects in the virtual space are the devices of a cause and effect interaction between the real world and the digital world.

The kinetics of the reaction that occurs when CO 2 and seawater are in contact is a complex function of temperature, alkalinity, final pH and TCO 2 which taken together determine the time required for complete equilibrium. This reaction is extremely important to the study of Ocean Acidification (OA) and is the critical technical driver in the Monterey Bay Aquarium Research Institute's (MBARI) Free Ocean CO 2 Enrichment (FOCE) experiments. The deep water FOCE science experiments are conducted at depths beyond scuba diver reach and demand that a valid perturbation experiment operate at a stable yet naturally fluctuating lower pH condition and avoid large or rapid pH variation as well as incomplete reactions, when we expose an experimental region or sample. Therefore, the technical requirement is to create a CO 2 source in situ that is stable and well controlled. After extensive research and experimentation MBARI has developed the ability to create an in situ source of CO 2 enriched seawater (ESW) for distribution and subsequent use in an ocean acidification experiment. The system mates with FOCE, but can be used in conjunction with other CO 2 experimental applications in deep water. The ESW system is completely standalone from FOCE.

Using the well developed Deep Ocean Raman In Situ Spectrometer (DORISS), we have developed an in situ deep-sea marine sediment pore water probe for geochemical studies. This novel device allows detailed measurement of pore water profiles. Our particular interest is in dissolved CH 4 , SO 4 =, H 2 S, and pH in situ without incurring artifacts due to the degassing that typically occurs with core recovery. A second generation DORISS instrument was developed at the Monterey Bay Aquarium Research Institute (MBARI) by engineering and science staff in 2005. The instrument is a plugin module for either of remotely operated vehicle (ROV) platforms at MBARI. DORISS has successfully performed in situ measurements on targets of scientific interest including high-temperature hydrothermal vent fluids, complex gas hydrates, and numerous other targets. Previously Raman techniques had been avoided to analyze sediment pore water geochemistry because of experience with the pore-waters strongly fluorescing. Simple experiments conducted with extracted pore-waters had previously demonstrated that fluorescence overwhelmed the relatively weak laser Raman signal. The in situ Raman pore water probe has worked around the fluorescence problem. The Raman pore water probe has been deployed a number of times at gas hydrate sites such as Hydrate Ridge, Barkley Canyon, and in the Santa Monica basin over the last two years. This paper will discuss the technique details and the exploration of expanding these same techniques into longer probes and looking at other difficult to obtain chemistries.

With rising concern over the impacts of ocean acidification on marine life there is a need for greatly improved techniques for carrying out in situ experiments. These must be able to create a ΔpH of 0.3 to 0.5 by addition of CO 2 for studies of natural ecosystems such as coral reefs, cold water corals, and other sensitive benthic habitats. Thus controlled CO 2 perturbation experiments in the field rather than in aquaria are quickly becoming an essential ocean science tool. Free Air CO 2 Enrichment (FACE) experiments have long been carried out on land to investigate the effects of elevated atmospheric CO 2 levels on vegetation. However, only limited work on CO 2 enrichment using quasi-open systems has yet been carried out in the ocean. Seawater CO 2 has complex chemistry with significantly slow reaction kinetics, unlike land-air experiments where simple mixing is the major concern. Ocean experimental designs must to take these reaction rates into account. The net result of adding a small quantity of CO 2 to seawater is to reduce the concentration of dissolved carbonate ion, and increase bicarbonate ion through the reaction: CO 2 + H 2 O + CO 3 2− → 2HCO 3 − The reaction between CO 2 and H 2 O is slow and is a complex function of temperature, pH, and TCO 2 . The reaction proceeds more rapidly at lower pH and higher temperatures. Marine animals in the natural ocean will typically experience only small and temporary shifts from environmental CO 2 equilibrium. Valid perturbation experiments must try to expose an experimental region to a near stable lower pH condition, and avoid large and rapid pH variability to the extent possible. This paper describes the design, development and testing of an in situ pH perturbation experiment deployed on a subsea cable for control. The paper addresses the differences between the deep-sea and shallow water versions of the experiments and addresses the pH sensor developments that enable long deployments.

Following adsorption of atomic hydrogen on Si(100)–(2×1), the surface is heated and the desorbed H2 is detected via (2+1) resonance‐enhanced multiphoton ionization (REMPI). H2 desorption correlated with the decomposition of dihydride groups on the surface (SiH2) is detected at a surface temperature Ts near 660 K, and with the monohydride species (SiH) near Ts=780 K. Although the H2 rotational distributions are nearly identical for the mono‐ and dihydride species, the vibrational distributions differ with roughly 0.2% and 1% of the population in H2(v=1) for the monohydride and dihydride, respectively. The enhancement in the [H2(v=1)]/[H2(v=0)] population ratio over that of a thermal distribution at Ts is, however, roughly 20 times for both mono‐ and dihydride species. The results are interpreted within a model that assumes desorption proceeds through a common intermediate, which is identified as the dihydride.

The dynamics of recombinative hydrogen desorption from the Si(100)‐(2×1) and Si(111)‐(7×7) surfaces have been compared using (2+1) resonance‐enhanced multiphoton ionization to probe the desorbed H2. After dosing the surface with disilane (Si2H6), we performed temperature programmed desorption in a quantum‐state‐specific manner. The rovibrational‐state distributions of H2 desorbed from both Si(100)‐(2×1) and Si(111)‐(7×7) are found to be the same within experimental accuracy. The rotational distribution is non‐Boltzmann and has an average energy significantly lower than kTs, where Ts is the surface temperature. In contrast, superthermal energy is observed in the vibrational degree of freedom, and the v=1 to v=0 population ratio is approximately 20 times higher than that predicted by Boltzmann statistics. Our results imply that the details of the recombinative desorption process that affect the product state distribution are remarkably insensitive to the structural differences between the surfaces. We sugge...

The desorption of hydrogen from the monohydride species on Si(100) has been studied state specifically using (2+1) resonance‐enhanced multiphoton ionization. The monohydride phase was prepared by dosing the surface with either disilane (Si2H6) or atomic hydrogen. Adsorption of disilane with subsequent desorption of H2 leads to the growth of an epitaxial silicon film, based on evidence obtained with scanning electron microscopy and low energy electron diffraction. We report that the rovibrational‐state distribution for hydrogen desorbed from Si(100) is the same after both disilane and atomic‐H adsorption. Hydrogen desorbs with low average rotational energy but with a population in the v=1 state enhanced by roughly 20 times over a thermal distribution at the temperature of the surface. The agreement between internal‐state distributions for both adsorption schemes indicates that the desorption of hydrogen during epitaxial growth of Si after Si2H6 adsorption proceeds in the same manner as that for a hydrogen‐...

We have measured vibrational‐ and rotational‐state distributions for H2, D2, and HD thermally desorbed from the monohydride phase on Si(100) surfaces using resonance‐enhanced multiphoton ionization detection. The ν=1 to ν=0 population ratio is roughly 20 times higher than that predicted by Boltzmann statistics at the surface temperature, Ts≊780 K. In contrast, the average rotational energies of the desorbed molecules are significantly lower than kTs, exhibit no isotopic dependence within experimental error, and are not significantly different in the ν=0 and ν=1 vibrational states. In the vibrational ground state, we find 〈Erot〉 =345±83 K, 451±77 K, and 332±57 K for H2, HD, and D2, respectively. The degree of vibrational excitation suggests that the H–H interatomic distance in the transition state is elongated compared with the gas‐phase equilibrium bond distance. The low average rotational energy clearly rules out recombination from a highly asymmetric transition state or recombination from high‐impact‐pa...

We have measured rotational distributions for H2 and D2 thermally desorbed from Si(100) surfaces using resonance‐enhanced multiphoton ionization (REMPI) for detection. These distributions are described by average rotational energies that are significantly lower than kTs (Ts=surface temperature) and exhibit slight, if any, isotopic dependence, i.e, 〈Erot(H2)〉=368±67 K and 〈Erot(D2)〉=348±65 K. The low average rotational energy clearly rules out recombination from a highly asymmetric transition state or recombination from high‐impact‐parameter collisions. The rotational distributions indicate that some dynamical constraint causes very little torque to be applied to molecular hydrogen during recombination. Our data may be interpreted as resulting from an exaggerated preference for reactive trajectories that are characterized by low‐impact parameters and/or a high degree of symmetry of the bond axis relative to the potential energy surface, followed by prompt desorption of the newly formed molecular hydrogen f...

Vibrational energy relaxation of molecules adsorbed at single crystal metal surfaces is measured by populating excited vibrational levels with picosecond infrared pump pulses and probing the population by infrared-visible sum frequency generation. Energy relaxation of the v=1 levels of the C-O stretching mode in CO/Cu(100) and of the symmetric C-H stretching mode of CH3S/Ag(111) are discussed.

The Monterey Bay Aquarium Research Institute (MBARI) has developed an AUV docking station for a 21-inch (54 cm) diameter AUV. The system was designed for operation with cabled undersea observatories in water depths up to 4 km deep and has been demonstrated in the open ocean, though at much shallower depths. The program demonstrated successful autonomous homing and docking, data downloads, uploading of new mission plans, battery recharging, and complete power cycling of the AUV. We describe the design, and at-sea tests.

The Monterey Bay Aquarium Research Institute (MBARI) has developed an autonomous underwater vehicle (AUV) for deep ocean seafloor mapping. The MBARI Mapping AUV is a 21" diameter, torpedo-shaped Dorado class vehicle equipped with a 200 kHz multibeam sonar, 110 kHz and 410 kHz chirp sidescan sonars, and a 2-16 kHz sweep chirp sub bottom profiler. The multibeam sonar incorporates a circular receive array conformal to the vehicle hull, providing 1 degree /spl times/ 1 degree beam resolution over a 150 degree swath. Navigation and attitude data are provided by an inertial navigation system integrating a laser ring gyro, accelerometers, and a 300 kHz Doppler velocity log (DVL). The vehicle is tracked during missions using an ultra-short baseline navigation system. The vehicle will also include acoustic modem and long-baseline navigation capabilities. A central cylindrical pressure housing contains all of the mapping sonar electronics. The main vehicle control and acoustic communications electronics are housed in a separate pressure housing in the vehicle tail section. Propulsion and steering are provided by a tailcone including an articulating propeller. Li-ion or Li-polymer battery packs allow for a 12 hour mission duration. The assembled package is rated to 6000 m depth. The mapping payload is also designed for ROV mounting, enabling low altitude (< 20 m) high precision missions in topographically challenging sites. The Mapping AUV has now been operated in both autonomous and ROV modes in and around the upper Monterey Canyon, successfully collecting high-resolution multibeam bathymetry and subbottom profile data. Near bottom surveys of the canyon axis achieve bathymetric coverage with a lateral resolution of 1 m and a vertical precision of 0.3 m. The subbottom profiler images subsurface structure to depths of 60 m in soft sediments.

The Monterey Bay Aquarium Research Institute (MBARI) is developing an autonomous seafloor mapping capability for deep ocean science applications. The MBARI Mapping AUV is a 0.53 m (21 in) diameter, 5.1 m (16.7 ft) long, Dorado-class vehicle designed to carry four mapping sonars. The primary sensor is a 200 kHz multibeam sonar producing swath bathymetry and sidescan. In addition, the vehicle carries 100 kHz and 410 kHz chirp sidescan sonars, and a 2-16 kHz sweep chirp subbottom profiler. Navigation and attitude data are obtained from an inertial navigation system (INS) incorporating a ring laser gyro and a 300 kHz Doppler velocity log (DVL). The vehicle also includes acoustic modem, ultra-short baseline navigation, and long-baseline navigation systems. A single cylindrical pressure housing contains all of the mapping sonar electronics, and the main vehicle control and acoustic communications electronics are housed in a separate glass ball. The Mapping AUV is powered by three 2 kWhr Li-polymer batteries, providing an expected mission duration of 12 hours at a typical speed of 1.5 m/s. The assembled package is rated to 6000 m depth, allowing MBARI to conduct high-resolution mapping of the deep-ocean seafloor. Initial at-sea testing commenced in May 2004 using the subbottom profiler and 100 kHz sidescan. The sonar package will also be mountable on ROV Ventana, allowing surveys at altitudes < 10 m at topographically challenging sites. The MBARI Seafloor Mapping team is now working towards integration of the multibeam sonar and towards achieving regular operations during 2005.

The original Odyssey vehicle systems established a style of platform that has proven to be extremely versatile and useful for a variety of scientific missions. The Monterey Bay Aquarium Research Institute (MBARI) has carried forward the Odyssey design, now called Dorado. Dorado is a mid-sized vehicle in comparison to other AUV systems. Dorado vehicles are 0.5334 m (21") diameter, and are designed for deep water (4500 m) operation. The Dorado design improves upon the original Odyssey versatility by dividing the vehicle up into modular sections. Specific sections can then be built to carry out each type of mission. A Dorado vehicle can then consist of a nose section, one or several mission-specific midbodies, and a tail section. The main vehicle systems for propulsion, control, data handling, navigation, acoustic sub-systems, and most other standard functions are housed in the tail section. This paper introduces the history of the Dorado systems, and what has been accomplished to date. This paper further describes the various architectural concepts and operational results. Future planning is also discussed.

The authors' goal is to greatly increase access to the Arctic Ocean by creating and demonstrating a safe and economical platform capable of basin-scale surveys. Specifically, they are developing an autonomous underwater vehicle (AUV) for Arctic research with unprecedented endurance, and the capability to relay data through the Ice to satellites. They provide a means of monitoring changes taking place in the Arctic Ocean and investigate its impact on global climate changes. The vehicle will also be capable of seafloor surveys throughout the Arctic basin. Such a capability is of national and global interest and importance.

The title oligomers have been incorporated in Zr-based layers on quartz substrates. Absorbance and emission spectra and fluorescence decays have been measured on these films and compared with data from solutions, powders, and PPV. The samples may be divided into those with “liquid-like” behavior and “solid-like” behavior; the latter is characterized by blue-shifted absorbance, red-shifted emission, and more complex decay dynamics than the former. By these criteria, the layers and PPV itself are decidedly “solid-like’.

The first excited vibrational level lifetime of CO in a c(2×2) overlayer on the Cu(100) surface is measured to be 3 ps.

The primary photodissociation channels of CH2BrI following excitation at 193.3, 210, and 248.5 nm have been studied with the crossed laser‐molecular beam technique. Product translational energy distributions and polarization dependences were derived for the primary dissociation processes observed. The data demonstrate bond selective photochemistry as well as some selective formation of electronically excited photofragments in bond fission and concerted dissociation. Excitation at 248.5 nm, which is assigned to excitation of primarily a n(I)→σ*(C–I) transition with some contribution from an overlapping n(Br)→σ*(C–Br) transition, results in both C–I and C–Br bond fission. C–I bond fission is the dominant channel, producing I atoms in both the 2P3/2 and spin‐orbit excited 2P1/2 states in a ratio of 1.0:0.75. Excitation at 193.3 nm, assigned to a transition to primarily predissociated Rydberg levels on the I atom, leads to C–Br bond fission, some C–I bond fission, and significant concerted elimination of IBr. Analysis of the product translational energy distributions for the dissociation products indicates that the IBr is formed electronically excited and that the halogen atom products are spin‐orbit excited. Excitation at 210 nm, of the transition assigned as n(Br)→σ*(C–Br) based on comparison with CH3Br, results in selective breaking of the stronger C–X bond in the molecule, the C–Br bond, and no fission of the C–I bond. Some concerted elimination of IBr also occurs; the IBr velocity distribution indicates it is probably formed electronically excited as in photolysis at 193.3 nm. The selective breaking of the C–Br bond over the weaker C–I bond is discussed in contrast to previous photolysis studies of polyhalomethanes.

Rotationally resolved experiments on the NO/Pt(111) system explore the mechanisms of inelastic scattering and trapping/desorption. The rotational dynamics associated with these two regimes are markedly different. A neat supersonic NO beam is scattered at normal incidence from a Pt(111) crystal at 375–475 K. The non‐Boltzmann rotational population distribution of the scattered species exhibits considerable rotational excitation beyond the energy available from the incident beam. Thus, a surface vibration to rotational energy transfer mechanism must be operative. The accompanying rotational alignment data reveal that highly excited rotational states exhibit predominantly ‘‘cartwheel’’ motion. In contrast, rotationally excited molecules that desorb from a 553 K Pt(111) surface show a preference for ‘‘helicopter’’ motion. The opposite preferences for rotational alignment in the two dynamical regimes provide insight into the anisotropy of molecule–surface interactions.

Operative management of Grade III acromioclavicular dislocations in young, active patients is a controversial issue with regard to operative management. Nine patients with complete dislocation (Allman Grade III) of the acromioclavicular joint who had undergone reconstruction of the coracoclavicular ligament with woven Dacron arterial grafts were reviewed clinically, radiologically and functionally utilizing an isokinetic dynamometer. Average follow-up was 2 years and 7 months. All results were good or excellent in terms of function, range of movement and patient acceptance. One patient developed a transient brachial plexus lesion due to compression caused by exuberant heterotopic calcification in the region of the synthetic ligament. One other exceptional patient continued to get more than occasional discomfort. It is concluded that Dacron loop repair is a relatively simple surgical technique with minimal morbidity and high efficacy in restoring stability and function in high demand patients.

Using photofragment translational spectroscopy, we have monitored the dissociation of CH2BrCH2I at 248, 266, and 308 nm, and CF2BrCF2I and CF2ICF2I at 308 nm. The primary fragments are I(2P3/2) and I(2P1/2) and the corresponding haloethyl radicals. The I(2P3/2) contribution decreases upon fluorination, but it is dominant for CH2BrCH2I at 308 nm. The electronic absorption dipole lies roughly along the C–I bond axis in every case. Stable CF2CF2Br and CF2CF2I radicals can be readily generated through photodissociation of the parent compounds, while stable CH2CH2Br could not be unambiguously observed. Upper limits to the reaction enthalpy at 0 K for CF2ICF2Br(I)→C2F4+I+Br(I) are 75±1(59±1) kcal/mol. The TOF spectra and related data suggest that there is a barrier to decomposition for CF2CF2I→C2F4+I that exceeds the C–I bond energy in the radical.