182 research outputs found
Conductance of electrolytes in 1-propanol solutions from â40 to 25°C
Conductance data for solutions of LiCl, NaBr, NaI, KI, KSCN, RbI, Et4NI, Pr4NI, Bu4NI, Bu4NClO4, n-Am4NI, i-Am4NI, n-Hept4NI, Me2Bu2NI, MeBu3NI, EtBu3NI, i-Am3BuNI, and i-Am3BuNBPh4 in 1-propanol at â40, â30, â20, â10, 0, 10, and 25°C are communicated and discussed. Evaluation of the data is performed on the basis of a conductance equation that includes a term in c3/2. Single ion conductances at 25 and 10°C are determined with the help of transference numbers t o + (KSCN/PrOH); the data are compared to data estimated by other methods. Ion-pair association constants and their temperature dependence are discussed in terms of contact and solvent separated ion pairs, and the role of non-coulombic forces is shown with the help of an appropriate splitting of the Gibbs energy of ion-pair formation
Post-fire erosion response and recovery, High Park Fire, Colorado
2014 Summer.Includes bibliographical references.Wildfires along the Colorado Front Range are increasing in extent, severity and frequency, and a better understanding of post-fire erosion processes is needed to manage burned lands. The objectives of this study were to: 1) document post-fire sediment production after the 2012 High Park Fire burn area, Colorado, 2) determine how sediment production relates to fire, rainfall, surface cover, soil and topographic characteristics, 3) model sediment yield at the study swales using the RUSLE and ERMiT erosion models and a site-specific multivariate regression (SSMR) model developed from the field measurements, and 4) assess how well the RUSLE and SSRM models performed when using remotely-sensed data in place of field-measured data. Sediment production, rainfall, surface cover, soil and topographic characteristics were measured for 29 swales in the High Park Fire burn area from August 2012 through September 2013. Eight of the swales were mulched with either wood shreds in October 2012 or straw in June 2013. Mean sediment yield from the unmulched swales in 2012 was 0.5 Mg ha-1 yr-1, increasing to 14.3 Mg ha-1 yr-1 in 2013. The increase in 2013 was largely due to above-average rainfall amounts. Mulched swales yielded 3.1 Mg ha-1 yr-1 in 2013. Precipitation thresholds for sediment production were best identified by rainfall erosivity. The erosivity threshold in 2012 was 3 MJ mm ha-1 hr-1 increasing to 22 MJ mm ha-1 hr-1 in 2013. Annual total sediment yield in 2013 was most closely correlated with rainfall erosivity whereas 2013 event sediment yield was more closely related by the thirty-minute maximum rainfall intensity. Independent variables with the strongest significant correlations to sediment yield were surface cover and topographic characteristics. Sediment yield was positively correlated with exposed bare soil in 2012 (Pearson's correlation coefficient [r] = 0.56) and negatively correlated with vegetation cover in 2013 (r = -0.46). Sediment yield was negatively correlated with percent cover by mulch (r = -0.97), but the type of mulch material did not affect sediment yield. Slope length was negatively correlated with sediment yield (r = -0.19), and narrower swales produced more sediment per unit area than wide swales. The best 2013 annual SSMR model used average percent bare soil in spring 2013, swale width-length ratio, summer erosivity, slope length and burn severity to predict sediment yield (R2 = 0.63). The two erosion models, ERMiT and RUSLE, did not accurately predict 2013 annual sediment yields. ERMiT under-predicted sediment yields for storms with maximum thirty-minute intensity recurrence intervals of 1.5-5 years, and over-predicted sediment yield for storms with precipitation depth recurrence intervals of 30-100 years. The RUSLE model run with field-measured independent variables similarly did not accurately predict sediment yield from the hillslopes (R2 = 0.05), and when the RUSLE variables were calculated with remotely sensed or GIS-derived data the correlation with measured values was even weaker (R2 = 0.02). The SSMR model developed from field-measured variables predicted sediment yield relatively well (R2 = 0.63), but declined when using remotely-derived data (R2 = 0.46). The results of this study show that rainfall erosivity and intensity, surface cover and topography are the dominant controls on post-fire sediment yield. The interactions of these controls is not captured in the existing erosion models ERMiT and RUSLE. Furthermore, the use of remote sensing and GIS to derive model inputs reduces the accuracy of these models
Factors Impacting Cliniciansâ Adoption of a Clinical Photo Documentation App and its Implications for Clinical Workflows and Quality of Care: Qualitative Case Study
Background: Mobile health (mHealth) tools have shown promise in clinical photo and wound documentation for their potential to improve workflows, expand access to care, and improve the quality of patient care. However, some barriers to adoption persist.
Objective: This study aims to understand the social, organizational, and technical factors affecting cliniciansâ adoption of a clinical photo documentation mHealth app and its implications for clinical workflows and quality of care.
Methods: A qualitative case study of a clinical photo and wound documentation app called imitoCam was conducted. The data were collected through 20 in-depth interviews with mHealth providers, clinicians, and medical informatics experts from 8 clinics and hospitals in Switzerland and Germany.
Results: According to the study participants, the use of mHealth in clinical photo and wound documentation provides numerous benefits such as time-saving and efficacy, better patient safety and quality of care, enhanced data security and validation, and better accessibility. The clinical workflow may also improve when the app is a good fit, resulting in better collaboration and transparency, streamlined daily work, clinician empowerment, and improved quality of care. The findings included important factors that may contribute to or hinder adoption. Factors may be related to the material nature of the tool, such as the perceived usefulness, ease of use, interoperability, cost, or security of the app, or social aspects such as personal experience, attitudes, awareness, or culture. Organizational and policy barriers include the available clinical practice infrastructure, workload and resources, the complexity of decision making, training, and ambiguity or lack of regulations. User engagement in the development and implementation process is a vital contributor to the successful adoption of mHealth apps.
Conclusions: The promising potential of mHealth in clinical photo and wound documentation is clear and may enhance clinical workflow and quality of care; however, the factors affecting adoption go beyond the technical features of the tool itself to embrace significant social and organizational elements. Technology providers, clinicians, and decision makers should work together to carefully address any barriers to improve adoption and harness the potential of these tools
Discovery of a New Deeply Eclipsing SU UMa-Type Dwarf Nova, IY UMa (= TmzV85)
We discovered a new deeply eclipsing SU UMa-type dwarf nova, IY UMa, which
experienced a superoutburst in 2000 January. Our monitoring revealed two
distinct outbursts, which suggest a superoutburst interval of ~800 d, or its
half, and an outburst amplitude of 5.4 mag. From time-series photometry during
the superoutburst, we determined a superhump and orbital period of 0.07588 d
and 0.0739132 d, respectively.Comment: 5 pages, 3 figures, accepted by PASJ lette
'The language of the naked facts': Joseph Priestley on language and revealed religion
Joseph Priestley (1733-1804) is usually remembered for his experiments in natural
philosophy and celebrated for his isolation of the gas we now call oxygen. However,
Priestley had a wide range of interests and published extensively on education, history,
politics, political philosophy, language, theology and religion. He dedicated his life to
elucidating a coherent set of epistemological, metaphysical and theological principles
which he believed explained the human mind, the natural world and the nature of God
and revelation. Recent studies of Priestley have emphasised the difficulties that arise
from isolating the various aspects of his thought and the fruitful outcome of uncovering
the many connections between his diverse areas of study. With this in mind, the present
dissertation aims to elucidate the relationship between two aspects of Priestleyâs thought
that have not previously been studied together. It examines his theory of language and
argument alongside his work on theology and the evidences of revelation. Chapter One
provides an overview of Priestleyâs epistemology, focusing on his work on induction,
judgment and assent. Chapter Two looks at Priestleyâs analysis of the role of the
passions in our assent to propositions and the progressive generation of the personality,
while paying particular attention to the origins of figurative language. Chapter Three
examines Priestleyâs theory of language development including the relationship
between figurative language and the extension of vocabulary and the close connection
between language and culture. Chapter Four demonstrates that Priestleyâs discussion of
the evidences of revealed religion is structured around his theory of assent and
judgment. It also explains how assent to revelation is essential for the generation and
transcendence of the âselfâ. Chapter Five brings all the themes of the dissertation
together in a discussion of Priestleyâs rational theology and examines his analysis of
figurative language in scripture
Photometric study of new southern SU UMa-type dwarf novae and candidates: V877 Ara, KK Tel and PU CMa
We photometrically observed three dwarf novae V877 Ara, KK Tel and PU CMa. We
discovered undisputed presence of superhumps in V877 Ara and KK Tel, with mean
periods of 0.08411(2) d and 0.08808(3) d, respectively. Both V877 Ara and KK
Tel are confirmed to belong to long-period SU UMa-type dwarf novae. In V877
Ara, we found a large decrease of the superhump period (dot(P)/P = -14.5 +/-
2.1 x 10^(-5)). There is evidence that the period of KK Tel decreased at a
similar or a more exceptional rate. Coupled with the past studies of superhump
period changes, these findings suggest that a previously neglected diversity of
phenomena is present in long-period SU UMa-type dwarf novae. The present
discovery of a diversity in long-period SU UMa-type systems would become an
additional step toward a full understanding the dwarf nova phenomenon. PU CMa
is shown to be an excellent candidate for an SU UMa-type dwarf nova. We
examined the outburst properties of these dwarf novae, and derived
characteristic outburst recurrence times. Combined with the recently published
measurement of the orbital period of PU CMa, we propose that PU CMa is the
first object filling the gap between the extreme WZ Sge-type and ER UMa-type
stars.Comment: 12 pages, 14 figures, accepted for publication in MNRA
A New SU UMa-Type Dwarf Nova, QW Serpentis (= TmzV46)
We report on the results of the QW Ser campaign which has been continued from
2000 to 2003 by the VSNET collaboration team. Four long outbursts and many
short ones were caught during this period. Our intensive photometric
observations revealed superhumps with a period of 0.07700(4) d during all four
superoutbursts, proving the SU UMa nature of this star. The recurrence cycles
of the normal outbursts and the superoutbursts were measured to be 50
days and 240(30) days, respectively. The change rate of the superhump period
was -5.8x10^{-5}. The distance and the X-ray luminosity in the range of 0.5-2.4
keV are estimated to be 380(60) pc and log L_x = 31.0 \pm 0.1 erg s^{-1}. These
properties have typical values for an SU UMa-type dwarf nova with this
superhump period.Comment: 9 pages, 12 figures, to appear in the VSNET special issue of PAS
Systemic Exosomal Delivery of shRNA Minicircles Prevents Parkinsonian Pathology
The development of new therapies to slow down or halt the progression of Parkinson's disease is a health care priority. A key pathological feature is the presence of alpha-synuclein aggregates, and there is increasing evidence that alpha-synuclein propagation plays a central role in disease progression. Consequently, the downregulation of alpha-synuclein is a potential therapeutic target. As a chronic disease, the ideal treatment will be minimally invasive and effective in the long-term. Knockdown of gene expression has clear potential, and siRNAs specific to alpha-synuclein have been designed; however, the efficacy of siRNA treatment is limited by its short-term efficacy. To combat this, we designed shRNA minicircles (shRNA-MCs), with the potential for prolonged effectiveness, and used RVG-exosomes as the vehicle for specific delivery into the brain. We optimized this system using transgenic mice expressing GFP and demonstrated its ability to downregulate GFP protein expression in the brain for up to 6 weeks. RVG-exosomes were used to deliver anti-alpha-synuclein shRNA-MC therapy to the alpha-synuclein preformed-fibril-induced model of parkinsonism. This therapy decreased alpha-synuclein aggregation, reduced the loss of dopaminergic neurons, and improved the clinical symptoms. Our results confirm the therapeutic potential of shRNA-MCs delivered by RVG-exosomes for long-term treatment of neurodegenerative diseases
Nitrogen yield advantage from grass-legume mixtures is robust over a wide range of legume proportions and environmental conditions
Coordination of this project was supported by the EU Commission through COST Action 852 âQuality legume-based forage systems for contrasting environmentsâ. A636 contribution to the research leading to these results has been conducted as part of the Animal Change project which received funding from the European Unionâs Seventh Framework Programme (FP7/2007-20 13) under the grant agreement no. 266018.peer-reviewedCurrent challenges to global food security require sustainable intensification of agriculture through initiatives that include more efficient use of nitrogen (N), increased protein self-sufficiency through home-grown crops, and reduced N losses to the environment. Such challenges were addressed in a continental-scale field experiment conducted over three years, in which the amount of total nitrogen yield (Ntot) and the gain of N yield in mixtures as compared to grass monocultures (Ngainmix) was quantified from four-species grass-legume stands with greatly varying legume proportions. Stands consisted of monocultures and mixtures of two N2 fixing legumes and two non-fixing grasses.The amount of Ntot of mixtures was significantly greater (P †0.05) than that of grass monocultures at the majority of evaluated sites in all three years. Ntot and thus Ngainmix increased with increasing legume proportion up to one third of legumes. With higher legume percentages, Ntot and Ngainmix did not continue to increase. Thus, across sites and years, mixtures with one third proportion of legumes attained ~95% of the maximum Ntot acquired by any stand and had 57% higher Ntot than grass monocultures.Realized legume proportion in stands and the relative N gain in mixture (Ngainmix/Ntot in mixture) were most severely impaired by minimum site temperature (R = 0.70, P = 0.003 for legume proportion; R = 0.64, P = 0.010 for Ngainmix/Ntot in mixture). Nevertheless, the relative N gain in mixture was not correlated to site productivity (P = 0.500), suggesting that, within climatic restrictions, balanced grass-legume mixtures can benefit from comparable relative gains in N yield across largely differing productivity levels.We conclude that the use of grass-legume mixtures can substantially contribute to resource-efficient agricultural grassland systems over a wide range of productivity levels, implying important savings in N fertilizers and thus greenhouse gas emissions and a considerable potential for climate change mitigation.European Unio
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