Influence of human pressures on large river structure and function

A large river study was conducted as part of the Cross Departmental Research Pool (CDRP) ecological integrity project to (i) provide an overview of the macroinvertebrate faunas of large rivers, including those in deep-water habitats, and (ii) to elucidate links between these faunas, river function and anthropogenic stressors. Eleven sites on 6th-order or 7th-order rivers were sampled; four in the South Island and seven in the North Island. We measured (i) macroinvertebrate communities colonising wood, riffles (where present), littoral habitats (1.5 m deep) (ii) ecosystem metabolism using a single-station open-channel approach based on natural changes in dissolved oxygen concentration over a 24-hour period, and (iii) wood and cellulose breakdown. Relationships were investigated between these response variables and reach-scale assessments of habitat quality, underlying upstream and segment environmental variables provided in the Freshwater Environments of New Zealand (FWENZ) database, and anthropogenic pressure variables provided by the Waters of National Importance (WONI) database

Rotationally Modulated X-ray Emission from T Tauri Stars

We have modelled the rotational modulation of X-ray emission from T Tauri stars assuming that they have isothermal, magnetically confined coronae. By extrapolating surface magnetograms we find that T Tauri coronae are compact and clumpy, such that rotational modulation arises from X-ray emitting regions being eclipsed as the star rotates. Emitting regions are close to the stellar surface and inhomogeneously distributed about the star. However some regions of the stellar surface, which contain wind bearing open field lines, are dark in X-rays. From simulated X-ray light curves, obtained using stellar parameters from the Chandra Orion Ultradeep Project, we calculate X-ray periods and make comparisons with optically determined rotation periods. We find that X-ray periods are typically equal to, or are half of, the optical periods. Further, we find that X-ray periods are dependent upon the stellar inclination, but that the ratio of X-ray to optical period is independent of stellar mass and radius.Comment: 10 pages, 8 figures, accepted for publication in MNRA

Enhanced heat transport by turbulent two-phase Rayleigh-B\'enard convection

We report measurements of turbulent heat-transport in samples of ethane (C$_2$H$_6$) heated from below while the applied temperature difference $\Delta T$ straddled the liquid-vapor co-existance curve $T_\phi(P)$. When the sample top temperature $T_t$ decreased below $T_\phi$, droplet condensation occurred and the latent heat of vaporization $H$ provided an additional heat-transport mechanism.The effective conductivity $\lambda_{eff}$ increased linearly with decreasing $T_t$, and reached a maximum value $\lambda_{eff}^*$ that was an order of magnitude larger than the single-phase $\lambda_{eff}$. As $P$ approached the critical pressure, $\lambda_{eff}^*$ increased dramatically even though $H$ vanished. We attribute this phenomenon to an enhanced droplet-nucleation rate as the critical point is approached.Comment: 4 gages, 6 figure

Heat Stress Effect on Immune Function in Dairy Cattle

This information was presented at the 2017 Cornell Nutrition Conference for Feed Manufacturers, organized by the Department of Animal Science In the College of Agriculture and Life Sciences at Cornell University. Softcover copies of the entire conference proceedings may be purchased at http://ansci.cals.cornell.edu/extension-outreach/adult-extension/dairy-management/order-proceedings-resources.This presentation will cover recent work examining the impact of heat stress in late gestation on the cow and the calf, during the dry period and subsequent lactation, including the effects on immune function. The presentation will also address the effects of heat stress on health and performance of lactating dairy cows, and use of an immune modulator to reduce the impacts of heat stress

Tackling the inescapable : mental ill health in later life. Report on a series of conversations.

Background to the project Older people with mental health problems (OPMHP) are a sub group of both mental health service users and older people service users. The specific voice OPMHP is therefore diluted within these general groups and there is little evidence to inform our understanding of the experiences of OPMHP. Project aims and objectives This project aimed to engage in conversation with older people who have experienced mental health problems with a view to hearing OPMHP perspectives and identifying priorities for future research. Methodology and methods Twelve people met though contacts with local services and community contacts contributed. Their ages ranged from 52-86 and there were 7 men and 5 women. Six meetings/conversations were held (individually or in small groups) during a three month period April-July 2017. Each conversation built on findings from the previous meeting/conversation. The conversations were shaped by the questions: What does ‘older person’ mean to you? ‘What matters in mental health care for older people’? (Including discussion about what was meant by ‘age appropriate’) and ‘What should be researched’? Conversations about preliminary findings were continued at a feedback event on 3rd July 2017 attended by seven of the contributors. Analysis and Findings The predefined categories ‘older people’, mental health care and age appropriateness’ and ‘research’ shaped the conversations. The older people category found mixed and contradictory ideas about what older person meant. A content analysis of the categories ‘mental health care and age appropriateness’, and ‘research’ was conducted by ‘within’ and ‘across’ analysis of the transcribed notes from the six meetings/conversations and found eight themes: Mutuality, Sensitivity, Carers, Exclusion, Meaning and purpose, Politics, Physical and mental health integration, and Mortality. Discussion Although limitations include: a small number of people, lack of diversity, and took place in only one location, the depth of the discussions was wide ranging. The themes overlapped somewhat but some new insights emerged which are perhaps not well explored in literature or policy. The idea of age appropriateness was confusing and was not defined but was conflated with illness and frailty. There was an emphasis on ageism that is in contrast with mental health policy that does not address the complexity of (indirect) discrimination on the basis of age for OPMH. Conclusion and Next steps Although this report only includes the views of twelve people it raises a number of important issues that are worthy of further exploration. This is particularly important for policy and commissioners who need to progress on the basis of up to date evidence. The consultation will inform development for research proposals and bids following exploratory literature reviews on topics raised

Working relationships for sustainability: Improving work-based relationships in local government to bring about sustainability goals

Theres no escape: we are always in relationship. Being aware of this matters. Doing something to build constructive relationships for sustainability, matters even more. This paper considers the connection between good relationships and effective sustainability work in local government. It draws on the collective experiences of four practitioners who have worked over many years in, with or for local government and argues that a good deal of project success is contingent upon the development of positive relationships with stakeholders, contractors, communities, businesses, colleagues, partners and other agencies and agency officers

The first magnetic maps of a pre-main sequence binary star system - HD 155555

We present the first maps of the surface magnetic fields of a pre-main sequence binary system. Spectropolarimetric observations of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) system were obtained at the Anglo-Australian Telescope in 2004 and 2007. Both datasets are analysed using a new binary Zeeman Doppler imaging (ZDI) code. This allows us to simultaneously model the contribution of each component to the observed circularly polarised spectra. Stellar brightness maps are also produced for HD 155555 and compared to previous Doppler images. Our radial magnetic maps reveal a complex surface magnetic topology with mixed polarities at all latitudes. We find rings of azimuthal field on both stars, most of which are found to be non-axisymmetric with the stellar rotational axis. We also examine the field strength and the relative fraction of magnetic energy stored in the radial and azimuthal field components at both epochs. A marked weakening of the field strength of the secondary star is observed between the 2004 and 2007 epochs. This is accompanied by an apparent shift in the location of magnetic energy from the azimuthal to radial field. We suggest that this could be indicative of a magnetic activity cycle. We use the radial magnetic maps to extrapolate the coronal field (by assuming a potential field) for each star individually - at present ignoring any possible interaction. The secondary star is found to exhibit an extreme tilt (~75 deg) of its large scale magnetic field to that of its rotation axis for both epochs. The field complexity that is apparent in the surface maps persists out to a significant fraction of the binary separation. Any interaction between the fields of the two stars is therefore likely to be complex also. Modelling this would require a full binary field extrapolation.Comment: 17 pages, 12 figures, accepted for publication in MNRA

The Angular Momentum Evolution of Very Low Mass Stars

We present theoretical models of the angular momentum evolution of very low mass stars (0.1 - 0.5 M_sun) and solar analogues (0.6 - 1.1 M_sun). We investigate the effect of rotation on the effective temperature and luminosity of these stars. We find that the decrease in T_eff and L can be significant at the higher end of our mass range, but becomes negligible below 0.4 M_sun. Formulae for relating T_eff to mass and v_rot are presented. We compare our models to rotational data from young open clusters of different ages to infer the rotational history of low mass stars, and the dependence of initial conditions and rotational evolution on mass. We find that the qualitative conclusions for stars below 0.6 M_sun do not depend on the assumptions about internal angular momentum transport, which makes these low mass stars ideal candidates for the study of the angular momentum loss law and distribution of initial conditions. We find that neither models with solid body nor differential rotation can simultaneously reproduce the observed stellar spin down in the 0.6 to 1.1 M_sun mass range and for stars between 0.1 and 0.6 M_sun. The most likely explanation is that the saturation threshold drops more steeply at low masses than would be predicted with a simple Rossby scaling. In young clusters there is a systematic increase in the mean rotation rate with decreased temperature below 3500 K (0.4 M_sun). This suggests either inefficient angular momentum loss or mass-dependent initial conditions for stars near the fully convective boundary. (abridged)Comment: To appear in the May 10, 2000 Ap