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You can lead a horse to water⌠are clinical students getting the message about the library and information skills support that is available?
Cambridge University Library is the recipient of a grant from the Arcadia Trust
to investigate issues and challenges in delivering academic library services in the
digital era. One project under this auspice has been IRIS: Induction, Research
and Information Skills, which attempted to map the information skills and needs
of students at Cambridge University. The results of this study will be used to provide
information in planning future services and facilities for students. Students
were invited to complete an online survey asking about which online information
resources they use most frequently, from whom they hear about new resources,
and where they go for help with information-seeking. Librarians across the tripartite
Cambridge system, in 60 college, department, and University libraries,
were also surveyed with regard to what training, induction, and support they
offered and to whom. This article will focus on the responses of 115 medical students
who participated in the survey, accounting for 6.5% of the total survey
responses. While acknowledging that student respondents were self-selecting, the
results raise questions about how well the librariansâ message is getting across
and how librarians can better serve students in the digital age
Serotonin drives a novel GABAergic synaptic current recorded in rat cerebellar purkinje cells: a lugaro cell to purkinje cell synapse
We recorded a novel fast GABAergic synaptic current in cerebellar Purkinje cells in rat brain slices using patch-clamp techniques. Because of a relatively low sensitivity to bicuculline, these currents can be recorded under conditions in which basket and stellate cell inputs are blocked. The observations that the novel synaptic currents occur spontaneously only in the presence of serotonin, and the specific limited positions in the slice from which they can be electrically evoked, suggest that the presynaptic cell is the Lugaro cell. Cell-attached recordings confirm that the Lugaro cell is the only interneuron in the cerebellar cortex with firing behavior consistent with the spontaneous activity recorded in Purkinje cells. The input shows a strong presynaptic modulation mediated by GABAA receptors, resulting in a dynamic range from almost 0 to >90% release probability. Modeling GABAA receptor responses to different GABA transients suggests that the relatively low sensitivity of the synaptic currents to bicuculline, compared with the higher affinity GABAA receptor antagonist SR-95531 (2-(3-carboxypropyl)-3-amino-6-(4-methoxyphenyl) pyridazinium), is attributable to an unusually long GABA dwell time and/or high GABA concentration in the synaptic cleft. The significance of this novel input is discussed in relation to other GABAergic synapses impinging on Purkinje cells. We suggest that the release of GABA onto Purkinje cells from Lugaro cells would primarily occur during motor activity under conditions in which the activity of basket and stellate cells might be inhibited
Photometry of the Stingray Nebula (V839 Ara) from 1889-2015 Across the Ionization of Its Planetary Nebula
Up until around 1980, the Stingray was an ordinary B1 post-AGB star, but then
it suddenly sprouted bright emission lines like in a planetary nebula (PN), and
soon after this the Hubble Space Telescope (HST) discovered a small PN around
the star, so apparently we have caught a star in the act of ionizing a PN. We
report here on a well-sampled light curve from 1889 to 2015, with unique
coverage of the prior century plus the entire duration of the PN formation plus
three decades of its aftermath. Surprisingly, the star anticipated the 1980's
ionization event by declining from B=10.30 in 1889 to B=10.76 in 1980. Starting
in 1980, the central star faded fast, at a rate of 0.20 mag/year, reaching
B=14.64 in 1996. This fast fading is apparently caused by the central star
shrinking in size. From 1994-2015, the V-band light curve is almost entirely
from the flux of two bright [OIII] emission lines from the unresolved nebula,
and it shows a consistent decline at a rate of 0.090 mag/year. This steady
fading (also seen in the radio and infrared) has a time scale equal to that
expected for ordinary recombination within the nebula, immediately after a
short-duration ionizing event in the 1980s. We are providing the first direct
measure of the rapidly changing luminosity of the central star on both sides of
a presumed thermal pulse in 1980, with this providing a strong and critical set
of constraints, and these are found to sharply disagree with theoretical models
of PN evolution.Comment: ApJ accepted, 54 pages, 4 figures, one long data tabl
Serotonin drives a novel GABAergic synaptic current recorded in rat cerebellar purkinje cells: a lugaro cell to Purkinje cell synapse
We recorded a novel fast GABAergic synaptic current in cerebellar Purkinje cells in rat brain slices using patch-clamp techniques. Because of a relatively low sensitivity to bicuculline, these currents can be recorded under conditions in which basket and stellate cell inputs are blocked. The observations that the novel synaptic currents occur spontaneously only in the presence of serotonin, and the specific limited positions in the slice from which they can be electrically evoked, suggest that the presynaptic cell is the Lugaro cell. Cell-attached recordings confirm that the Lugaro cell is the only interneuron in the cerebellar cortex with firing behavior consistent with the spontaneous activity recorded in Purkinje cells. The input shows a strong presynaptic modulation mediated by GABAA receptors, resulting in a dynamic range from almost 0 to >90% release probability. Modeling GABAA receptor responses to different GABA transients suggests that the relatively low sensitivity of the synaptic currents to bicuculline, compared with the higher affinity GABAA receptor antagonist SR-95531 (2-(3-carboxypropyl)-3-amino-6-(4-methoxyphenyl) pyridazinium), is attributable to an unusually long GABA dwell time and/or high GABA concentration in the synaptic cleft. The significance of this novel input is discussed in relation to other GABAergic synapses impinging on Purkinje cells. We suggest that the release of GABA onto Purkinje cells from Lugaro cells would primarily occur during motor activity under conditions in which the activity of basket and stellate cells might be inhibited
Converting rain into drinking water: Quality issues and technological advances
With growing pressures on water supplies worldwide, rainwater harvesting is increasingly seen as a viable option to provide drinking water to an ever expanding population, particularly in developing countries. However, rooftop runoff is not without quality issues. Microbiological and chemical contamination have been detected in several studies, well above local and international guidelines, posing a health risk for consumers. Our research explores the use of silver ions, combined with conventional filtration and settling mechanisms, as a safe and affordable model for purification that can be applied on a small scale. The complete systems were installed and tested in rural communities in a Mexican semi-arid region. Efficiencies up to 99.9% were achieved in the removal of indicator microorganisms, with a marked exception where cross-contamination from external seepage occurs. Sites without overhanging branches or with relatively clean surfaces show an absence of total coliforms in the untreated runoff, compared with others where values as high as 1,650 CFU/100 ml were recorded. Thus, given adequate maintenance, the system can successfully deliver high quality drinking water, even when storage is required for long periods of time. Š IWA Publishing 2011
Dollarization and Economic Performance: What Do we Really Know?
In this paper we analyze the macroeconomic record of dollarized economies. In particular, we investigate whether, as its supportersâ claim, dollarization is associated with lower inflation and faster growth. We analyze this issue by using a matching estimator technique developed in the training evaluation literature. Our findings suggest that inflation has been significantly lower in dollarized nations than in non-dollarized ones. We also find that dollarized nations have had a lower rate of economic growth than non-dollarized ones. Finally, we find that macroeconomic volatility is not significantly different across dollarized and non-dollarized economies. We conjecture that the lower rate of economic growth in dollarized countries is due, at least in part, to these countriesâ difficulties in accommodating external disturbances, such as major term of trade and capital flows shocks.
Independent Currency Unions, Growth, and Inflation
During the last few years, there has been a renewed interest in currency unions. This is the result both of the recent wave of currency crises as well as the implementation of the euro. In this paper, the authors use panel data for 1970-98 to investigate economic performance under historical independent currency unions (ICUs) along three dimensions: GDP per capital growth, growth volatility, and inflation. They use a treatment effects model that estimates jointly the probability of having a common currency and its effect on performance. The authors find that ICU countries have had a significantly lower rate of inflation, but macroeconomic volatility has been higher. Also, ICU countries have grown faster than with currency nations, but the East Caribbean Currency Area countries are found to be the driving force behind this result.
Strict Dollarization and Economic Performance: An Empirical Investigation
In this paper we analyze the macroeconomic record of 'strictly dollarized' economies. In particular we investigate whether dollarized countries have historically exhibited faster growth and lower volatility than countries with a domestic currency. We analyze this issue by using a treatment regression analysis that estimates jointly the probability of being a dollarized country, and outcome equations. Our analysis indicates that the probability of being a dollarized country depends on regional, geographical, political and structural variables. Our results also suggest GDP per capita growth has not been statistically different in dollarized and in non-dollarized ones. We also find that volatility has been significantly higher in dollarized than in non-dollarized economies. These results are robust to the estimation technique, and to the sample used.
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