Miniature Piezoelectric Shaker for Distribution of Unconsolidated Samples to Instrument Cells

The planned Mars Science Laboratory mission requires inlet funnels for channeling unconsolidated powdered samples from the sampling and sieving mechanisms into instrument test cells, which are required to reduce cross-contamination of the samples and to minimize residue left in the funnels after each sample transport. To these ends, a solid-state shaking mechanism has been created that requires low power and is lightweight, but is sturdy enough to survive launch vibration. The funnel mechanism is driven by asymmetrically mounted, piezoelectric flexure actuators that are out of the load path so that they do not support the funnel mass. Each actuator is a titanium, flextensional piezoelectric device driven by a piezoelectric stack. The stack has Invar endcaps with a half-spherical recess. The Invar is used to counteract the change in stress as the actuators are cooled to Mars ambient temperatures. A ball screw is threaded through the actuator frame into the recess to apply pre-stress, and to trap the piezoelectric stack and endcaps in flexure. During the vibration cycle of the flextensional actuator frame, the compression in the piezoelectric stack may decrease to the point that it is unstressed; however, because the ball joint cannot pull, tension in the piezoelectric stack cannot be produced. The actuators are offset at 120 . In this flight design, redundancy is required, so three actuators are used though only one is needed to assist in the movement. The funnel is supported at three contact points offset to the hexapod support contacts. The actuator surface that does not contact the ring is free to expand. Two other configurations can be used to mechanically tune the vibration. The free end can be designed to drive a fixed mass, or can be used to drive a free mass to excite impacts (see figure). Tests on this funnel mechanism show a high density of resonance modes between 1 and 20 kHz. A subset of these between 9 and 12 kHz was used to drive the CheMin actuators at 7 V peak to peak. These actuators could be driven by a single resonance, or swept through a frequency range to decrease the possibility that a portion of the funnel surface was not coincident with a nodal line (line of no displacement). The frequency of actuation can be electrically controlled and monitored and can also be mechanically tuned by the addition of tuning mass on the free end of the actuator. The devices are solid-state and can be designed with no macroscopically moving parts. This design has been tested in a vacuum at both Mars and Earth ambient temperatures ranging from 30 to 25

The Mars Science Laboratory Touchdown Test Facility

In the Touchdown Test Program for the Mars Science Laboratory (MSL) mission, a facility was developed to use a full-scale rover vehicle and an overhead winch system to replicate the Skycrane landing event

Integrated Carbon Budget Models for the Everglades Terrestrial-Coastal-Oceanic Gradient: Current Status and Needs for Inter-Site Comparisons

Recent studies suggest that coastal ecosystems can bury significantly more C than tropical forests, indicating that continued coastal development and exposure to sea level rise and storms will have global biogeochemical consequences. The Florida Coastal Everglades Long Term Ecological Research (FCE LTER) site provides an excellent subtropical system for examining carbon (C) balance because of its exposure to historical changes in freshwater distribution and sea level rise and its history of significant long-term carbon-cycling studies. FCE LTER scientists used net ecosystem C balance and net ecosystem exchange data to estimate C budgets for riverine mangrove, freshwater marsh, and seagrass meadows, providing insights into the magnitude of C accumulation and lateral aquatic C transport. Rates of net C production in the riverine mangrove forest exceeded those reported for many tropical systems, including terrestrial forests, but there are considerable uncertainties around those estimates due to the high potential for gain and loss of C through aquatic fluxes. C production was approximately balanced between gain and loss in Everglades marshes; however, the contribution of periphyton increases uncertainty in these estimates. Moreover, while the approaches used for these initial estimates were informative, a resolved approach for addressing areas of uncertainty is critically needed for coastal wetland ecosystems. Once resolved, these C balance estimates, in conjunction with an understanding of drivers and key ecosystem feedbacks, can inform cross-system studies of ecosystem response to long-term changes in climate, hydrologic management, and other land use along coastlines

Supplementing the capability maturity model with the personal software process

Bibliography: p. 87-8

A Capable and Temporary Test Facility on a Shoestring Budget: The MSL Touchdown Test Facility

This slide presentation reviews the construction of a test facility for the Mars Science Laboratory landing on Mars

Cocconeis tsara Riaux-Gobin, Witkowski & Bemiasa 2021, sp. nov.

<i>Cocconeis tsara</i> Riaux-Gobin, Witkowski & Bemiasa <i>sp. nov.</i> LM Figs 1–8; SEM Figs 9–29 <p> <b>Description</b>: Valve small, elliptic. Valve length 11–19 µm (mean 16 µm ± 1.5); valve width 7–12 µm (mean 10 µm ± 1.1); L/ W 1.7 ± 0.2; n = 64 (SEM). <b>SV</b>: convex, striae radiate and regularly spaced, uniseriate comprised of subround to square subdivided areolae with rounded corners (Figs 9–12) becoming multiseriate on the valve margin (up to triseriate with alternate areolae, Figs 9, 12) comprised of smaller undivided areolae. SV striae 13–17 in 10 µm (mean 14 µm ± 1.0). SV areolae appear round-elliptic in phase-contrast (Fig. 1), while squared in Nomarski differential interference-contrast (Figs 4–6). Externally, hymenes of areolae nearly level with valve surface (Figs 10–11). Areolae open internally by a sub-round to elliptic aperture giving access to a loculate areola (Fig. 17). In internal view, one thin bar (up to two) axially arranged (= primary bar/s), merges with one bar transapically oriented on the bottom of the small chamber (= secondary bar), resulting in an irregular to asymetrical cross (Figs 10–11, 17, 63). Exceptionally, presence of diamond-like structure (more or less irregular or incomplete) on rare marginal loculate areolae (Figs 12–13). All sectors of loculate areolae externally closed by hymenes with short slits perpendicular to the frame of each sector (Figs 10–11). SVVC strong and closed, ornamented by digitate fimbriae with irregular apex (Figs 14, 16). SVVC fimbria present on each virga, or more rarely, on each three to four virgae (Fig. 14). Narrow cingulum composed of few cingular bands/copulae. <b>RV</b>: Slightly concave, with a marginal hyaline rim, striae uniseriate up to the margin (Figs 18–22). RV striae 18–25 in 10 µm (mean 20 µm ± 1.6), composed of regularly spaced round areolae. No RV areolae on apices. Central area reduced, external proximal raphe endings closely spaced, straight, slightly expanded (Figs 23–25), terminal raphe endings simple, far from margin (Figs 20–22). RV areolae externally closed by slightly concave hymenes with short slits perpendicular to the frame of the areolae. RVVC open, with hammer-like fimbriae taking place on an elevated-raised rim, each two to three virgae (Figs 27–28). Between each large fimbria, an undulation, reminiscent a vestigial fimbria, faces each virga (Fig. 29, arrowheads). Each fimbria ornamented on its abvalvar side by an oblong and smooth papilla (no furrows, Figs 27–29). Second RV copula with a ligula.</p> <p> <b>Holotype, here assigned</b>: Slide BM 101 951 (NHM) from the sample 17– ANAK.</p> <p> <b>Isotypes</b>: Slides mounted with the same material as the holotype sample 17– ANAK: slide SZCZ 26006 in A. Witkowski collection (The Faculty of Geosciences, Szczecin, Poland) and slide 17– ANAK in C. Riaux-Gobin collection (CRIOBE – CNRS, USR 3278, Perpignan, France).</p> <p> <b>Type locality</b>: Coral reef on the Western coast of Anakao (Madagascar, Indian Ocean), sample 17– ANAK (Table 1).</p> <p> <b>Etymology</b>: The specific epithet ‘ <i>tsara</i> ’ refers to the Malagasy word meaning beautiful.</p> <p> <b>Habitat</b>: Epiphyte on <i>Bleakeleya</i> cf. <i>notata</i> (Grunow in Van Heurck) Round, living on macroalgae from a coral reef environment composed of diverse living corals.</p> <p> <b>Remarks</b>: <i>Cocconeis tsara sp. nov.</i> is most similar to <i>C. scutellum</i> var. <i>posidoniae</i> De Stefano, D.Marino & Mazzella (De Stefano <i>et al.</i> 2000, 2008). The two taxa can be distinguished by differences in frustule ultrastructure. <i>Cocconeis scutellum</i> var. <i>posidoniae</i> has SV areolae subdivided into two hymenate, and axially arranged, reniform structures (figs 75, 77– 78 in De Stefano <i>et al.</i> 2000), sometimes showing a central ‘pierced’ structure (fig. 79 in De Stefano <i>et al.</i> 2000). In contrast, the SV areolae of <i>C. tsara</i> are cruciately or near-cruciately divided by thin crossbars, irregular or distorted (Figs 10–11, 63) and the hymenate sectors are triangular, with rounded edges on the areola perimeter (Figs 10–11, 17). The RVVC of <i>C. scutellum</i> var. <i>posidoniae</i> is closed (fig. 83 in De Stefano <i>et al.</i> 2000) while that of <i>C. tsara sp. nov.</i> is open (Fig. 20). The RVVC fimbriae of <i>C. scutellum</i> var. <i>posidoniae</i> are joined at their terminus forming large quadrangular fenestrae (figs 76, 83, 85 in De Stefano <i>et al.</i> 2000) while the fimbriae of <i>C. tsara</i> are free on the interior edge (Figs 27–29), and ending by a spathulate or hammer-like structure (Fig. 27 arrows). The RV striation is marginally biseriate in <i>C. scutellum</i> var. <i>posidoniae</i> (figs 82, 86 in De Stefano <i>et al.</i> 2000) while uniseriate in <i>C. tsara</i> (Figs 18, 26). The papillae on the RVVC fimbriae in <i>C. scutellum</i> var. <i>posidoniae</i> are ornamented by numerous furrows, while the papillae are smooth and rod-like in <i>C. tsara</i> (Figs 27–29).</p> <p> Valves slightly smaller and more elongate than <i>C. tsara sp. nov.</i> were found as epizoic on ‘Océane’ (juvenile <i>Chelonia mydas</i> Linnaeus, Haapiti, Moorea, South Pacific, Figs 30–33) [valve length 10–11 µm (mean 11 µm ± 0.6); valve width 4–6 µm (mean 5.4 µm ± 0.5); L/W 2 ± 0.2; n = 12. SV striae 18–21 in 10 µm (mean 19 µm ± 1.4)]. <i>Cocconeis</i> cf. <i>tsara</i> has a similar SV loculate areola arrangement, but the areolae are sometimes further divided by additional cross-bars forming a zig-zag or arborescent arrangement of the hymenate sectors (Fig. 33). No RV was associated with certainty to the latter taxon (only two RV observed, with dense striation, that may as well pertain to <i>Cocconeis coronatoides</i> Riaux-Gobin & O.E.Romero, in Riaux-Gobin <i>et al.</i> (2011a: 88), which was also present in the sample in rare abundance). A vestigial raphe was also present on the SV (Figs 30–31, circles).</p>Published as part of <i>Riaux-Gobin, Catherine, Frankovich, Thomas, Witkowski, Andrzej, Agudelo, Pablo Saenz-, Esteve, Peter, Ector, Luc & Bemiasa, John, 2021, Cocconeis tsara sp. nov., C. santandrea sp. nov. and allied taxa pertaining to the new section Loculatae, pp. 145-169 in Phytotaxa 484 (2)</i> on pages 147-151, DOI: 10.11646/phytotaxa.484.2.1, <a href="http://zenodo.org/record/5421470">http://zenodo.org/record/5421470</a&gt

Cocconeis santandrea Riaux-Gobin, Witkowski & Bemiasa 2021, sp. nov.

<i>Cocconeis santandrea</i> Riaux-Gobin, Witkowski & Bemiasa <i>sp. nov.</i> SEM Figs 34–54 <p> <b>Description</b>: Valves robust, oblong-elliptic. Valve length 16–24 µm (mean 21.5 µm ± 2.0); valve width 12–16 µm (mean 13 µm ± 1.5); L/ W 1.6 ± 0.2; n = 25 (SEM). <b>SV</b>: Convex. Striae radiate and regularly spaced, uniseriate on valve face comprised of larger areolae, becoming multiseriate (up to quadriseriate with alternate areolae, Figs 34, 36) and comprised of smaller areolae in the last 1/3 of the valve and mantle (Figs 34–36, 40). SV striae 9–13 µm (mean 9.6 µm ± 1.0). SV with regular axial rows of slightly squared areolae, externally concave, opening internally by a round foramina (Figs 40–41). Loculate areolae concave, cross-shaped, delineated by four small pegs in axial and transverse positions that extend towards the center of the areola, but never merging in the center of the areola (Figs 37, 39, 41). Each peg frequently externally ornamented by one or two round warts (Figs 37, 39, arrowheads). Hymenes perforated by small pores (Fig. 39, white arrow), with a row of short slits only on the periphery. Marginal pyramidal group of small areolae also occluded by hymenes with pores (not shown). Hymenes strongly internally domed at their center (Fig. 41, short arrow). SVVC with digitate fimbriae regularly aligned with SV striae (Figs 36, 38). <b>RV</b>: Concave, with a marginal hyaline rim positioned far from the valve margin (Figs 42, 45), striae uniseriate up to the margin and biseriate with alternate areolae afterwards, with a specific ‘ears of wheat’ pattern (Fig. 43, arrowhead). Note one row of round and larger areolae close to the hyaline area (Figs 43 <b>–</b> 44, arrows). RV striae 15–18 in 10 µm (mean 17 ± 0.9), composed of regularly spaced, small and round areolae. Areolae present on apices. Areola hymenate occlusions with radiate irregular slits (Fig. 51). Raphe narrow, straight. Central area small (Fig. 46). External proximal raphe endings closely spaced, straight, slightly expanded (Fig. 46), internally deflected in opposite directions (Fig. 49). Helictoglossae almost straight (Fig. 48). Internal sub-marginal raised rim, with small and regular bumps facing each stria (Fig. 50). RVVC with fimbriae irregularly spaced, and joined at their terminus, creating large rectangular fenestrae (Fig. 52, arrowhead). RVVC papillae oblong with up to 5 furrows (Figs 53 <b>–</b> 54, arrowheads).</p> <p> <b>Holotype, here assigned</b>: SEM stub BM001222256 (NHM) from the sample Rapa–1.</p> <p> <b>Type locality</b>: Intertidal turf, Rapa (Austral Archipelago, South Pacific), sample Rapa–1 (Table 1). Also found in Nuku-Hiva (Marquesas Archipelago) on intertidal red turf, sample NH4–2.</p> <p> <b>Etymology</b>: The epithet ‘ <i>santandrea</i> ’ refers to the X-shaped (or decussate) cross of St. Andrew.</p> <p> <b>Habitat</b>: Epipsammic on coral sand grains and epiphytic on short turf from coral reef environments in the South Pacific.</p> <p> <b>Remarks</b>: <i>Cocconeis santandrea</i> is most similar to <i>C. nosybetiana</i> sharing a loculate SV areola structure with areola subdivided into sectors by pegs. <i>Cocconeis santandrea</i> can be distinguished from <i>C. nosybetiana</i> by the structure of the loculate SV areolae. The decussate areolae of <i>C. santandrea</i> are split into 4 sectors, while those of <i>C. nosybetiana</i> are transversely split into two parts. <i>Cocconeis santandrea</i> is also slightly larger than <i>C. nosybetiana</i> (16–24 µm versus 9–21 µm, respectively), with SV hymenate occlusions with pores in place of short slits in a rhombic pattern. <i>Cocconeis santandrea</i> also exhibits a greater SV stria density (15–18 in 10 µm) compared to <i>C. nosybetiana</i> (13–16 in 10 µm). The valve outline of <i>C. santandrea</i> is oblong-elliptic versus round-elliptic in <i>C. nosybetiana</i>. When describing <i>C. nosybetiana</i>, Riaux-Gobin <i>et al.</i> (2019b) also observed some rare loculate <i>Cocconeis</i> SV valves that were larger in size than other <i>C. nosybetiana</i> valves and possessed decussate areolae (op. cit., figs 27–30). Those depicted specimens from Madagascar were originally believed to be larger forms of <i>C. nosybetiana</i>, but after examination of a greater number of specimens of <i>C. santandrea</i> observed from the Marquesas and Rapa Archipelagos, those larger specimens (referred to as <i>Cocconeis</i> sp. 2 in Tables 2 & 4, Figs 66, 76–77), are now suspected to be <i>C. santandrea</i>. The SV areola of the Madagascar specimens are slightly smaller in diameter than those specimens described in the present study (600 nm versus 800–1200 nm, respectively). The SV areola morphology of <i>C. nosybetiana</i> is now understood to be limited to those forms with areolae that are partially divided into semi-circular areas delimited by 2 or 3 (when close to the sternum), transapically-located pegs (see figs 12–24 in Riaux-Gobin <i>et al.</i> 2019b). Forms with decussately divided SV areolae with 4 apically and transapically pegs are now considered as <i>C. santandrea</i>.</p>Published as part of <i>Riaux-Gobin, Catherine, Frankovich, Thomas, Witkowski, Andrzej, Agudelo, Pablo Saenz-, Esteve, Peter, Ector, Luc & Bemiasa, John, 2021, Cocconeis tsara sp. nov., C. santandrea sp. nov. and allied taxa pertaining to the new section Loculatae, pp. 145-169 in Phytotaxa 484 (2)</i> on pages 152-155, DOI: 10.11646/phytotaxa.484.2.1, <a href="http://zenodo.org/record/5421470">http://zenodo.org/record/5421470</a&gt

US-Cuba Scientific Collaboration: Emerging Issues and Opportunities in Marine and Related Environmental Sciences

Despite diplomatic nonrecognition, vast political differences, a long-standing trade embargo, and strict limitations on travel, US-Cuban scientific collaboration is on the rise. In December 2011, independent US scientists traveled to Havana, Cuba, for a series of scientific discussions with members of the Cuban scientific community. The American Association for the Advancement of Science (AAAS) and the Cuban Academy of Sciences facilitated the trip. One topic for discussion concerned emerging issues and opportunities in marine and related environmental sciences. Shared resources (e.g., Gulf of Mexico fisheries) and high connectivity between US and Cuban ecosystems via regional oceanic and atmospheric circulations underscore the importance of increased US-Cuban cooperation in this field

US-Cuba Scientific Collaboration: Emerging Issues and Opportunities in Marine and Related Environmental Sciences

Despite diplomatic nonrecognition, vast political differences, a long-standing trade embargo, and strict limitations on travel, US-Cuban scientific collaboration is on the rise. In December 2011, independent US scientists traveled to Havana, Cuba, for a series of scientific discussions with members of the Cuban scientific community. The American Association for the Advancement of Science (AAAS) and the Cuban Academy of Sciences facilitated the trip. One topic for discussion concerned emerging issues and opportunities in marine and related environmental sciences. Shared resources (e.g., Gulf of Mexico fisheries) and high connectivity between US and Cuban ecosystems via regional oceanic and atmospheric circulations underscore the importance of increased US-Cuban cooperation in this field