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Purpose: Oncoplastic breast-conserving surgery (OPBCS) may be a better option than mastectomy ± immediate breast reconstruction (IBR) for women with breast cancer but studies directly comparing the techniques are lacking. We surveyed UK breast units to determine the current practice of OPBCS to inform the design of a future comparative study. Methods: An electronic survey was developed to explore the current practice of OPBCS. This included the local availability of volume displacement and/or replacement techniques; number of cases performed; contraindications and approach to contralateral symmetrisation. Summary data for each survey item were calculated and overall provision of care examined. Results: 58 UK centres completed the survey, including 43 (74%) stand-alone breast and 15 (26%) combined breast/plastics units. Over 40% of units (n = 24) treated more than 500 cancers/year. Most units offered volume displacement techniques (TMs) (97%). Over two-thirds (n = 39. 67%) of units offered local perforator flaps (LPF). Approximately a half of units (10/19) not performing LPF were planning to introduce them in the next 12–24 months. A third (n = 19, 33%) of units routinely performed simultaneous contralateral symmetrisation mostly with two-surgeon operating. There were limited oncological restrictions to OPBCS with no contraindications for multifocal cancers in most centres; 65% of units (36/55) offered OPBCS for multicentric disease. Extensive DCIS was a contraindication in a minority of units. Conclusions: OPBCS is widely available in the UK but contraindications and approaches to contralateral symmetrisation were variable. Work is now needed to prospectively evaluate the outcomes of OPBCS vs mastectomy ± IBR to support informed decision-making. [ABSTRACT FROM AUTHOR]

Every three years, the International VLBI Service for Geodesy and Astrometry (IVS) has carried out a continuous observing campaign (CONT) with the goal of demonstrating state-of-the art Very Long Baseline Interferometry (VLBI) observing since 2002. In 2017, the campaign was unique in two respects: three independent networks ran simultaneously and one of the networks was a demonstration of new VLBI Global Observing System (VGOS) technology. Two 14-station legacy station networks, CONT17-L1 and CONT17-L2 observed in S/X mode and the third network, CONT17-VGOS, consisted of five stations observing in VGOS broadband mode. We investigated the differences between Earth Orientation Parameters (EOPs) and scale parameters estimated from the simultaneous observing sessions of the three networks. Prior studies could not determine VLBI EOP precision or VLBI network biases within the VLBI technique. For CONT17, EOP (X-pole, Y-pole, and UT1) biases between the CONT17-L2 and CONT17-L1 networks were - 11 ± 12 μ as, - 19 ± 13 μ as, - 1.1 ± 1.0 μ s, which are at the 1-sigma level. X-pole, Y-pole, and UT1 biases between the CONT17-VGOS and CONT17-L1 networks were - 108 ± 24 μ as, - 17 ± 23 μ as, 1.4 ± 0.6 μ s. Three corner hat analysis of the CONT17-L1, CONT17-L2, and Global Navigation Satellite System (GNSS) series yielded X and Y polar motion precisions of CONT17-L1: 19.8 μ as, 22.4 μ as; CONT17-L2: 41.0 μ as, 35.2 μ as; GNSS: 19.8 μ as, 15.0 μ as. Session scale parameter precisions of the CONT17-L1 and CONT17-L2 networks based on the standard deviation of their respective scale series are 0.45 ppb and 0.30 ppb. Baseline length repeatabilities for each of the networks indicate that the length precision versus length of the VGOS network is about 0.4 ppb compared to 0.5 ppb for the CONT17-L2 network and 0.6 ppb for the CONT17-L1 network for baselines of length less than 10,000 km. [ABSTRACT FROM AUTHOR]

The use of trophy hunting as a wildlife management option has been a highly controversial topic, especially in southern Africa, but trophy hunting has historically also taken place also throughout Asia. In China, trophy hunting was the topic of intense public discussion more than a decade ago, leading ultimately to the suspension of this practice in 2006. Yet, this debate was dominated by urban voices, with no formal consultation of rural populations from minorities such as the Tibetan herders who previously benefited financially from commercial trophy hunting acting as guides and who are also concerned about the negative impact of rising blue sheep numbers on livestock grazing. We used a discrete choice experiment econometric method to better understand the trade‐offs made by both urban and rural populations across China in relation trophy hunting as a rural development and wildlife management tool. We find that trophy hunting is supported by the majority of rural residents but opposed by most urban residents, although there is heterogeneity within both these groups. We recommend that policy‐making in this realm should be informed by a better understanding of the preferences of different stakeholders, including the local people who bear the costs of living with wildlife. [ABSTRACT FROM AUTHOR]

NASA maintains and operates a global network of Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and Global Navigation Satellite System ground stations as part of the NASA Space Geodesy Program. The NASA Space Geodesy Network (NSGN) provides the geodetic products that support Earth observations and the related science requirements as outlined by the US National Research Council (NRC in Precise geodetic infrastructure: national requirements for a shared resource, National Academies Press, Washington, 2010. http://nap.edu/12954, Thriving on our changing planet: a decadal strategy for Earth observation from space, National Academies Press, Washington, 2018. http://nap.edu/24938). The Global Geodetic Observing System (GGOS) and the NRC have set an ambitious goal of improving the Terrestrial Reference Frame to have an accuracy of 1 mm and stability of 0.1 mm per year, an order of magnitude beyond current capabilities. NASA and its partners within GGOS are addressing this challenge by planning and implementing modern geodetic stations colocated at existing and new sites around the world. In 2013, NASA demonstrated the performance of its next-generation systems at the prototype next-generation core site at NASA's Goddard Geophysical and Astronomical Observatory in Greenbelt, Maryland. Implementation of a new broadband VLBI station in Hawaii was completed in 2016. NASA is currently implementing new VLBI and SLR stations in Texas and is planning the replacement of its other aging domestic and international legacy stations. In this article, we describe critical gaps in the current global network and discuss how the new NSGN will expand the global geodetic coverage and ultimately improve the geodetic products. We also describe the characteristics of a modern NSGN site and the capabilities of the next-generation NASA SLR and VLBI systems. Finally, we outline the plans for efficiently operating the NSGN by centralizing and automating the operations of the new geodetic stations. [ABSTRACT FROM AUTHOR]

Environmental non‐governmental organizations (ENGOs) largely select flagship species for conservation marketing based on their aesthetic appeal. However, little is known about the fundraising effectiveness of this approach or how it compares to ecosystem conservation campaigns that use habitat types as flagships. By performing a willingness to donate (WTD) survey of potential online donors from Finland, we identified which motivations and donor characteristics influence their preferences for a range of different flagship species and ecosystems. Using the contingent valuation method and the payment card approach, we found the combined funding for eight mammal flagship species was 29% higher funding than for eight bird flagship species. Furthermore, the aesthetically more appealing species, as well as the species and ecosystems that are native to Finland, attracted the most funding. We then used ordinal logistic regression to identify the factors influencing a donor's WTD, finding that knowledge of biodiversity conservation and familiarity with the flagship was associated with an increased WTD to birds and ecosystems, and people with higher education levels had an increased WTD to ecosystems. Surprisingly, species aesthetic appeal was not related to an increased WTD, although "need of conservation" was, suggesting that highlighting the plight of these less appealing threatened species or ecosystems could raise money. Our results suggest that the factors driving donating to mammals, birds or ecosystems differ, and so underline the importance of considering the diverse motivations behind donation behaviour in fundraising campaigns. They also provide new evidence of the motivations of online donors, an under‐studied group who are likely to become an increasingly important source of conservation funding. [ABSTRACT FROM AUTHOR]

Continuous (CONT) VLBI campaigns have been carried out about every 3 years since 2002. The basic idea of these campaigns is to acquire state-of-the-art VLBI data over a continuous time period of about 2 weeks to demonstrate the highest accuracy of which the current VLBI system is capable. In addition, these campaigns support scientific studies such as investigations of high-resolution Earth rotation, reference frame stability, and daily to sub-daily site motions. The size of the CONT networks and the observing data rate have increased steadily since 1994. Performance of these networks based on reference frame scale precision and polar motion/LOD comparison with global navigation satellite system (GNSS) earth orientation parameters (EOP) has been substantially better than the weekly operational R1 and R4 series. The precisions of CONT EOP and scale have improved by more than a factor of two since 2002. Polar motion precision based on the WRMS difference between VLBI and GNSS for the most recent CONT campaigns is at the 30 $$\upmu $$ as level, which is comparable to that of GNSS. The CONT campaigns are a natural precursor to the planned future VLBI observing networks, which are expected to observe continuously. We compare the performance of the most recent CONT campaigns in 2011 and 2014 with the expected performance of the future VLBI global observing system network using simulations. These simulations indicate that the expected future precision of scale and EOP will be at least 3 times better than the current CONT precision. [ABSTRACT FROM AUTHOR]

Variations in continental water storage lead to loading deformation of the crust with typical peak-to-peak variations at very long baseline interferometry (VLBI) sites of 3-15 mm in the vertical component and 1-2 mm in the horizontal component. The hydrology signal at VLBI sites has annual and semi-annual components and clear interannual variations. We have calculated the hydrology loading series using mass loading distributions derived from the global land data assimilation system (GLDAS) hydrology model and alternatively from a global grid of equal-area gravity recovery and climate experiment (GRACE) mascons. In the analysis of the two weekly VLBI 24-h R1 and R4 network sessions from 2003 to 2010 the baseline length repeatabilities are reduced in 79 % (80 %) of baselines when GLDAS (GRACE) loading corrections are applied. Site vertical coordinate repeatabilities are reduced in about 80 % of the sites when either GLDAS or GRACE loading is used. In the horizontal components, reduction occurs in 70-80 % of the sites. Estimates of the annual site vertical amplitudes were reduced for 16 out of 18 sites if either loading series was applied. We estimated loading admittance factors for each site and found that the average admittances were 1.01 $$\pm $$ 0.05 for GRACE and 1.39 $$\pm $$ 0.07 for GLDAS. The standard deviations of the GRACE admittances and GLDAS admittances were 0.31 and 0.68, respectively. For sites that have been observed in a set of sufficiently temporally dense daily sessions, the average correlation between VLBI vertical monthly averaged series and GLDAS or GRACE loading series was 0.47 and 0.43, respectively. [ABSTRACT FROM AUTHOR]

The ' Big Five' charismatic megafauna concept is considered key for financial competitiveness of protected areas in South Africa. However, this Western colonial concept is also leading to an underappreciation of wider biodiversity and the recovery of other endangered species. This study assessed the heterogeneity of tourist preferences for big game species in Kwa Zulu- Natal, South Africa, using a choice experiment approach, employing latent class modelling, in order to identify tourists' segments not necessarily drawn to the Big Five. The latent class segmentation identified two segments for both international and national tourists, largely defined by socio-economic characteristics. Less experienced and wealthier tourists were mostly interested in charismatic megafauna, while more experienced, but lower income tourists showed preferences for a broader range of species. Exploring viewing preferences in this way illustrates the potential to realign conservation businesses to achieve biodiversity conservation objectives. In the short term, managing protected areas for the Big Five and other favourite species will continue to deliver significant financial benefits to local stakeholders, but policy makers should consider using financial mechanisms to subsidize conservation actions for less charismatic species and develop the biodiversity base of safari tourism in South Africa. [ABSTRACT FROM AUTHOR]

Adenosine 5'-triphosphate (ATP) mediates a variety of biological functions following nerve-evoked release, via activation of either Gprotein- coupled P2Y- or ligand-gated P2X receptors. In smooth muscle, ATP, acting via P2Y receptors (P2YR), may act as an inhibitory neurotransmitter. The underlying mechanism(s) remain unclear, but have been proposed to involve the production of inositol 1,4,5- trisphosphate [Ins(1,4,5)P3] by phospholipase C (PLC), to evoke Ca2+ release from the internal store and stimulation of Ca2+-activated potassium (KCa) channels to cause membrane hyperpolarization. This mechanism requires Ca2+ release from the store. However, in the present study, ATP evoked transient Ca2+ increases in only ~10% of voltage-clamped single smooth muscle cells. These results do not support activation of KCa as the major mechanism underlying inhibition of smooth muscle activity. Interestingly, ATP inhibited Ins(1,4,5)P3-evoked Ca2+ release in cells that did not show a Ca2+ rise in response to purinergic activation. The reduction in Ins(1,4,5)P3-evoked Ca2+ release was not mimicked by adenosine and therefore, cannot be explained by hydrolysis of ATP to adenosine. The reduction in Ins(1,4,5)P3-evoked Ca2+ release was, however, also observed with its primary metabolite, ADP, and blocked by the P2Y1R antagonist, MRS2179, and the G protein inhibitor, GDPbS, but not by PLC inhibition. The present study demonstrates a novel inhibitory effect of P2Y1R activation on Ins(1,4,5)P3-evoked Ca2+ release, such that purinergic stimulation acts to prevent Ins(1,4,5)P3- mediated increases in excitability in smooth muscle and promote relaxation. [ABSTRACT FROM AUTHOR]

Time-series of zenith wet and total troposphere delays as well as north and east gradients are compared, and zenith total delays ( ZTD) are combined on the level of parameter estimates. Input data sets are provided by ten Analysis Centers (ACs) of the International VLBI Service for Geodesy and Astrometry (IVS) for the CONT08 campaign (12-26 August 2008). The inconsistent usage of meteorological data and models, such as mapping functions, causes systematics among the ACs, and differing parameterizations and constraints add noise to the troposphere parameter estimates. The empirical standard deviation of ZTD among the ACs with regard to an unweighted mean is 4.6 mm. The ratio of the analysis noise to the observation noise assessed by the operator/software impact (OSI) model is about 2.5. These and other effects have to be accounted for to improve the intra-technique combination of VLBI-derived troposphere parameters. While the largest systematics caused by inconsistent usage of meteorological data can be avoided and the application of different mapping functions can be considered by applying empirical corrections, the noise has to be modeled in the stochastic model of intra-technique combination. The application of different stochastic models shows no significant effects on the combined parameters but results in different mean formal errors: the mean formal errors of the combined ZTD are 2.3 mm (unweighted), 4.4 mm (diagonal), 8.6 mm [variance component (VC) estimation], and 8.6 mm (operator/software impact, OSI). On the one hand, the OSI model, i.e. the inclusion of off-diagonal elements in the cofactor-matrix, considers the reapplication of observations yielding a factor of about two for mean formal errors as compared to the diagonal approach. On the other hand, the combination based on VC estimation shows large differences among the VCs and exhibits a comparable scaling of formal errors. Thus, for the combination of troposphere parameters a combination of the two extensions of the stochastic model is recommended. [ABSTRACT FROM AUTHOR]

Within the International VLBI Service for Geodesy and Astrometry (IVS) Monte Carlo simulations have been carried out to design the next generation VLBI system ('VLBI2010'). Simulated VLBI observables were generated taking into account the three most important stochastic error sources in VLBI, i.e. wet troposphere delay, station clock, and measurement error. Based on realistic physical properties of the troposphere and clocks we ran simulations to investigate the influence of the troposphere on VLBI analyses, and to gain information about the role of clock performance and measurement errors of the receiving system in the process of reaching VLBI2010's goal of mm position accuracy on a global scale. Our simulations confirm that the wet troposphere delay is the most important of these three error sources. We did not observe significant improvement of geodetic parameters if the clocks were simulated with an Allan standard deviation better than 1 × 10 at 50 min and found the impact of measurement errors to be relatively small compared with the impact of the troposphere. Along with simulations to test different network sizes, scheduling strategies, and antenna slew rates these studies were used as a basis for the definition and specification of VLBI2010 antennas and recording system and might also be an example for other space geodetic techniques. [ABSTRACT FROM AUTHOR]

Background and Purpose: The sarcoplasmic reticulum (SR) releases Ca(2+) via inositol 1,4,5-trisphosphate receptors (IP(3)R) in response to IP(3)-generating agonists. Ca(2+) release subsequently propagates as Ca(2+) waves. To clarify the role of IP(3) production in wave generation, the contribution of a key enzyme in the production of IP(3) was examined using a phosphoinositide-specific phospholipase C (PI-PLC) inhibitor, U-73122.Experimental Approach: Single colonic myocytes were voltage-clamped in whole-cell configuration and cytosolic Ca(2+) concentration ([Ca(2+)](cyto)) measured using fluo-3. SR Ca(2+) release was evoked either by activation of IP(3)Rs (by carbachol or photolysis of caged IP(3)) or ryanodine receptors (RyRs; by caffeine).Key Results: U-73122 inhibited carbachol-evoked [Ca(2+)](cyto) transients. The drug also inhibited [Ca(2+)](cyto) increases, evoked by direct IP(3)R activation (by photolysis of caged IP(3)) and RyR activation (by caffeine), which do not require PI-PLC activation. U-73122 also increased steady-state [Ca(2+)](cyto) and slowed the rate of Ca(2+) removal from the cytoplasm. An inactive analogue of U-73122, U-73343, was without effect on either IP(3)R- or RyR-mediated Ca(2+) release.Conclusions and Implications: U-73122 inhibited carbachol-evoked [Ca(2+)](cyto) increases. However, the drug also reduced Ca(2+) release when evoked by direct activation of IP(3)R or RyR, slowed Ca(2+) removal and increased steady-state [Ca(2+)](cyto). These results suggest U-73122 reduces IP(3)-evoked Ca(2+) transients by inhibiting the SR Ca(2+) pump to deplete the SR of Ca(2+) rather than by inhibiting PI-PLC. [ABSTRACT FROM AUTHOR]

A reduction in the compression ratio can adversely affect the cold-start and idling performance of diesel engines. The problems and potential solutions have been investigated. Studies have been carried out to compare the indicated performances and heat release characteristics of a direct-injection diesel engine during low-speed cold operation at compression ratios of 18.4:1 and 15.4:1. The test engine was a naturally aspirated single-cylinder design with a swept volume of 0.5 l. Tests covered start temperatures between 10 °C and -20 °C. At around 300 r/min, the indicated work output was higher at the lower compression ratio as a result of lower blow-by, and the cycle-by-cycle stabilities of the heat release and work output were similar at both compression ratios. The cycle-by-cycle stability deteriorated with increasing engine speed. At 1000 r/min idling conditions, the stability was relatively poor and was worse for the low-compression-ratio case. At the high compression ratio, the cycle-by-cycle stability was improved by introducing multiple pilot injections and using metallic glow plugs operating at about 850 °C. At the low compression ratio, improvements in stability could not be achieved without switching to glow plugs operating at about 1100 °C. [ABSTRACT FROM AUTHOR]

The five sensory modalities of humans are also found in a wide range of invertebrates. Other vertebrates have evolved additional special senses, such as the magnetic sense, which are also found in some invertebrates. However, there remain a few sensory abilities that curiously appear to be found in either vertebrates or invertebrates, but not both. For example, electrosensitivity - the ability to detect electric fields in water - which should benefit vertebrates and invertebrates alike, is apparently only used by vertebrates. However, recent reports suggest that some invertebrates could have an electric sense. Here we examine that possibility further and demonstrate a behavioural threshold to low-level electrical fields in two freshwater invertebrates. The responses are not low enough for them to detect the Earth's magnetic field as some other electroreceptive species can do, but sufficiently low for them to use in navigation or prey and predator detection. This finding challenges the current view of the sensory world of aquatic invertebrates and has implications for the evolution of this ability. [ABSTRACT FROM AUTHOR]

Species selected as flagships to promote conservation activities around the world are typically well known and charismatic mega-fauna. Unfortunately this limits the scope for applying the concept as some critical areas for biodiversity conservation, such as tropical islands, lack such species. In this study, we explore the potential to apply the concept of ‘tourism flagship species’ to tropical island birds of the Seychelles, an archipelago of considerable importance for conservation that is highly dependent on international tourism. In particular we wish to identify which species attributes are most influential with regard to their potential for fundraising among international tourists. Using a choice experiment approach and using state-of-the-art econometric methods, we found that conservation attributes and physical appearance of the bird species are both important in terms of raising funds for conservation. Nevertheless, conservation attributes ranked higher in the respondents preferences. Our results suggest that there is considerable potential for a variety of species to effectively act as flagships in developing nations that are dependent on international tourism and rich in biodiversity but lack charismatic fauna. [ABSTRACT FROM AUTHOR]

Background and Purpose: The sarcoplasmic reticulum (SR), regulates the cytoplasmic Ca(2+) concentration ([Ca(2+)](cyto)) in vascular smooth muscle. Release from the SR is controlled by two intracellular receptor/channel complexes, the ryanodine receptor (RyR) and the inositol 1,4,5-trisphosphate receptor (IP(3)R). These receptors may be regulated by the accessory FK506-binding protein (FKBP) either directly, by binding to the channel, or indirectly via FKBP modulation of two targets, the phosphatase, calcineurin or the kinase, mammalian target of rapamycin (mTOR).Experimental Approach: Single portal vein myocytes were voltage-clamped in whole cell configuration and [Ca(2+)](cyto) measured using fluo-3. IP(3)Rs were activated by photolysis of caged IP(3) and RyRs activated by hydrostatic application of caffeine.Key Results: FK506 which displaces FKBP from each receptor (to inhibit calcineurin) increased the [Ca(2+)](cyto) rise evoked by activation of either RyR or IP(3)R. Rapamycin which displaces FKBP (to inhibit mTOR) also increased the amplitude of the caffeine-evoked, but reduced the IP(3)-evoked [Ca(2+)](cyto) rise. None of the phosphatase inhibitors, cypermethrin, okadaic acid or calcineurin inhibitory peptide, altered either caffeine- or IP(3)-evoked [Ca(2+)](cyto) release; calcineurin did not contribute to FK506-mediated potentiation of RyR- or IP(3)R-mediated Ca(2+) release. The mTOR inhibitor LY294002, like rapamycin, decreased IP(3)-evoked Ca(2+) release.Conclusions and Implications: Ca(2+) release in portal vein myocytes, via RyR, was modulated directly by FKBP binding to the channel; neither calcineurin nor mTOR contributed to this regulation. However, IP(3)R-mediated Ca(2+) release, while also modulated directly by FKBP may be additionally regulated by mTOR. Rapamycin inhibition of IP(3)-mediated Ca(2+) release may be explained by mTOR inhibition. [ABSTRACT FROM AUTHOR]

1. Wildlife make an important contribution to the rural economy; generating jobs, income and profits from food and sporting enterprises, and contributing in less direct ways by bringing pleasure from viewing and learning. This paper reviews the literature regarding the contribution made by wildlife to the rural economy and to British society more widely. The review focuses on UK studies published in peer-reviewed journals and official web-based sources in the last 20 years. 2. Traditional activities such as deer stalking remain an important source of wealth and employment, but their overall contribution is declining relative to non-consumptive uses such as wildlife tourism. 3. Much of the literature focuses on the negative impacts of mammals on commercial activities such as agriculture and forestry, even though these impacts are relatively insignificant in economic terms at both regional and national levels. 4. Wild meat provides a niche in the contemporary food market, but, although demand is growing, growth is handicapped by a fragmented supply chain and lack of marketing. 5. In comparison with other rural resources such as farming, the contribution made by wild mammals to the rural economy appears small, even in relatively remote regions, but this may partly reflect gaps in the literature regarding their contribution via less formal markets, hobby activities, and in supporting ecosystem equilibrium. [ABSTRACT FROM AUTHOR]

Appendages are important sources of sensory information for all animals that possess them but they are commonly damaged in nature. We describe how the tactile system of the crayfish Cherax destructor functioned when subjected to the kind of damage found in wild-caught or cultured animals. Touch information was methodically varied by the removal of antennae and chelae. The resulting behaviour was analysed in a T-maze. Crayfish with a single antenna ablated turned toward the intact appendage, however, those with only a partial ablation did not, suggesting that a tactile information threshold exists for normal behaviour. When exposed to the same environment after an antennal ablation but with no prior experience in that terrain, crayfish also turned toward the side of the intact antenna. By contrast, when animals with experience obtained in a previous trial with intact antennae were tested after ablation of one antenna, they did not turn into one arm of the maze more than the other. These two outcomes indicate that behaviour is affected by an interaction between the time at which an injury occurs and an animal's knowledge of the topography, and that an injury may affect learning. We also tested to see if other appendages could provide tactile information to compensate for antennal loss. Input from the chelae did not affect the turning behaviour of crayfish in the maze. [ABSTRACT FROM AUTHOR]

Touch is a principal sense in all animals. It is potentially important in species of freshwater crayfish that encounter murky waters or are nocturnal. Little is known about how tactile (touch) stimuli affect exploratory behaviour under these conditions. We placed animals in different tactile situations at the start of an exploration in a dark arena and tracked the position of the body and antennae to test whether subsequent search behaviour was affected. Individuals were exposed to differently textured walls, channelled out along a wall, or released in contact with no, one, or two walls. A corner arrangement of surfaces, where individuals started near two walls at right angles, produced behaviour that differed from that of other configurations; animals chose one wall and then maintained a close distance from the wall along which they were moving. The distance from a wall adopted by a crayfish walking parallel to it was affected by the texture of the wall. These results on the influence of tactile stimuli on crayfish exploratory behaviour may have implications for other taxa. [ABSTRACT FROM AUTHOR]

Resource managers are involved in difficult decisions that affect rare species and habitats but often lack relevant ecological knowledge and experience. Ecological models are increasingly being looked to as a means of assisting the decision-making process, but very often the data are missing or are unsuited to empirical modelling. This paper describes the development and application of the Delphi approach to develop a decision support tool for wildlife conservation and management. The Delphi process is an expert-based approach to decision support that can be used as a means for predicting outcomes in situations where ‘absolute’ or ‘objective’ models are unavailable or compromised by lack of appropriate data. The method aims to develop consensus between experts over several rounds of deliberation on the assumption that combining the expertise of several individuals will provide more reliable results than consulting one or two individuals. In this paper the approach is used to engineer soft knowledge on the conservation requirements of capercaillie Tetrao urogallus, an endangered woodland grouse, into a model that can be used by forests managers to improve the quality of forest habitat for capercaillie over extensive commercial forest areas. This paper concludes with a discussion of the potential advantages and disadvantages of Delphi and other soft knowledge approaches to ecological modelling and conservation management. [ABSTRACT FROM AUTHOR]

Monitoring of altimeter microwave radiometer measurements is necessary in order to identify radiometer drifts or offsets that in uncorrected will introduce systematic errors into ocean height measurements. To examine TOPEX Microwave Radiometer (TMR) and Jason-1 Microwave Radiometer (JMR) behavior, we have used coincident wet zenith delay estimates from Very Long Baseline Interferometry (VLBI) and Global Positioning System (GPS) geodetic sites near altimeter ground tracks. We derived a TMR patlt delay drift rate of -1.1 ± 0.1 mm/yr using GPS data for the period from 1993.0-1999.0 and -1.2 ± 0.5 mm/yr using VLBI data. Thereafter, the drift appears to have leveled off. Already after 2.3 years (82 cycles) of the Jason-1 mission, it is clear that there have been significant systematic errors in the JMR path delay measurements. From comparison with GPS wet delays, there is an offset of -5.2 ± 0.6 mm at about cycle 30 and a more abrupt offset of -11.5 ± 0.8 mm at cycle 69. If we look at the behavior of the JMR coldest brightness temperatures, we see that the offsets near cycle 30 and cycle 69 are mainly caused by corresponding offsets in the 23.8 GHz channel of -0.49 ± 0.12 K and -1.18 ± 0.13 K, although there is a small 34.0 GHz offset at cycle 69 of 0.75 ± 0.22 K. Drifts in the 18.0 and 34.0 GHz channels produce a small path delay drift of 0.3 ± 0.5 mm/yr. [ABSTRACT FROM AUTHOR]

Recordings were made from the nerve innervating the stretch receptors of the abdominal muscle receptor organs and slow extensor muscles of tethered crayfish, Cherax destructor, during so-called “non-giant swimming”. The stretch receptors were active during the flexor phase of swimming but the duration and pattern of activity varied from cycle to cycle. Their pattern of firing was modified by the activity of the large accessory neurons which make direct inhibitory synapses upon them. Neither the stretch receptors nor the accessory neurons were active during the extensor phase of the cycle. The timing and extent of tailfan movements during the period of stretch receptor activity were measured from video records before and after the stretch receptor nerves were cut in the second to fifth segments. The promotion of the tailfan during flexion was significantly delayed and the minimum angle to which the uropods were remoted at the end of flexion significantly larger in denervated animals. We propose that afferent information from the stretch receptors coordinates the timing and extent of tailfan movements according to variations in the positioning and movement of the abdominal segments such that the hydrodynamic efficiency of the tailfan is enhanced on a cycle by cycle basis during non-giant swimming. [ABSTRACT FROM AUTHOR]

The physiology and relationships of tonic cord stretch receptor neurons in the crayfish Cherax destructor were examined with intracellular and extracellular recording. Cord stretch evoked slow depolarisations leading to action potentials in tonic cord stretch receptor neurons. Intermittent post-synaptic potentials were also seen in cord stretch receptor neurons but were not the primary cause of the action potentials. Cord stretch still evoked action potentials in cord stretch receptor neurons when all synaptic activity, monitored at another known chemical synapse, was blocked using high [Mg2+] and low [Ca2+] in the bath. One source of facilitating excitatory post-synaptic potentials in the cord stretch receptor neurons was from mechanosensory hairs on the dorsal abdominal surface. Tonic cord stretch receptor neuron activity was associated with an increase in the activity of the abdominal slow extensor inhibitor motor neuron and at least one abdominal flexor excitor motor neuron in its segment, and reduced activity in the abdominal slow flexor inhibitor motor neuron. Activation of individual cord stretch receptor neurons produced a local resistance reflex. Cord stretch, activating many receptors, produced several other outcomes. One was the "extensor state" described in earlier literature. The tonic cord stretch receptor neurons of Cherax destructor appear to be stretch-sensitive interneurons that receive inputs from other elements of the abdominal control system and mediate polysynaptic reflex activity in postural motor neurons. [ABSTRACT FROM AUTHOR]

Two opposing muscle systems underlie abdominal contractions during escape swimming in crayfish. In this study we used extracellular and intracellular stimulation, recording and dye-filling to systematically identify each of the five deep extensor excitors and single inhibitor of the crayfish, Cherax destructor. Functional associations of each neuron were characterised by recording its responses to sensory and abdominal cord inputs, its extensor muscle innervation pattern, and its relationships with other neurons. Each excitor receives excitatory input from the tonic abdominal stretch receptors and the largest neuron also receives input from the phasic stretch receptor. The two largest excitors innervate the muscle bundle containing the fastest fibres and may be electronically coupled. The smaller neurons may also be electronically coupled and innervate the remaining deep extensor fibres which display dynamic characteristics from fast to medium-fast. The inhibitor does not receive input from the stretch receptors, but is strongly excited by tactile afferents. The implications of these findings for the current models of the control of abdominal tailflips and swimming are discussed. [ABSTRACT FROM AUTHOR]

Using extracellular and intracellular stimulation, recording and dye-filling, we identified and studied the superficial extensor motor neurons of the crayfish, Cherax destructor. Functional associations of each neuron were characterised by recording its responses to sensory and abdominal cord inputs, its extensor muscle innervation pattern and its relationships with other neurons. Two clear associations were found among the six neurons of each segment. A medium-sized excitor (no. 3), that innervates a substantial percentage of extensor muscle fibres, and the largest excitor (no. 6), recruited during peak, excitation, were inhibited by input from unknown interneurons that excited the common inhibitor (no. 5). Likewise, these excitors received excitatory input when the inhibitor was silent. Another medium-sized neuron (no. 4) that innervates many muscle fibres was co-active with one of the small excitors (no. 2). The two medium-sized neurons were never active at the same time, and these two groupings may be determined by pre-motor interneurons. The implications of these findings for our understanding of motor control in this system are discussed. [ABSTRACT FROM AUTHOR]

The skeletal morphology, musculature and innervation of the mandible of the common lobster, Homarus gammarus, are described as a basis for the functional study included in the two subsequent papers. Although the mandible articulation takes the form of a hinge with movement in a single plane, the musculature of the mandible is complex. The main muscles are similar to those of Astacus (Schmidt, 1915) but some smaller, previously undescribed muscles were found. As for Astacus (Keim, 1915) and Cambarus (Chaudonneret, 1956) the mandibular muscles are innervated by two nerve trunks, the inner and outer mandibular nerves. However, differences occur in the branching of these nerves and the muscles which they innervate. A group of sensory cells associated with the posterior stomach nerve (omn 4) are described. It is suggested that these form a proprioceptive organ associated with the hypodermis overlying the lateral mandible articulation. An interesting group of neurones lying at the confluence of nerve branches from omn 2, omn 3, and omn 4 is described. [ABSTRACT FROM AUTHOR]

Children showing a comorbid behavior pattern of hyperactivity-impulsivity-inattention and conduct problems (HIA + CP) were contrasted to children having only an internalizing and externalizing behavior pattern (I + E) and matched controls. Children displaying the HIA + CP behavior pattern were at greater risk on a number of outcome measures in social and academic domains beginning in Grade 3 and continuing into Grade 4. The most marked differences among the three groups were found on peer measures of rejection and friendship and teacher ratings of social skills. On average, almost two-thirds of the HIA + CP group were rejected by their peers compared to one-third of the I + E group and only 12.5% controls. Over 70% of the HIA + CP group had no reciprocated friendships from Grade 3 to Grade 4 compared to less than half of the I + E group and approximately one-fourth of controls. Contrary to much theorizing in the literature, the HIA + CP and I + E groups showed average levels of academic self-concept and did not differ from controls in on measures of social self-concept and academic self-concept and general self-esteem. These findings were interpreted in light of positive illusory biases and the established link between aggressive behavior and egotism. The current article offers partial support for Lynam's (1996) notion of the "fledgling psychopath." [ABSTRACT FROM AUTHOR]