1,002 research outputs found
(Pyridin-4-yl)methyl N′-(3-phenylallylidene)hydrazinecarbodithioate.
In the title compound, C16H15N3S2, the central C2N2S2 residue is planar (r.m.s. deviation = 0.045 Å) and the pyridyl and benzene rings are inclined and approximately coplanar to this plane, respectively [dihedral angles = 72.85 (9) and 10.73 (9)°], so that, overall, the molecule adopts an L-shape. The conformation about each of the N=C [1.290 (3) Å] and C=C [1.340 (3) Å] bonds is E. Supramolecular chains along [1-10] are stabilized by N—H(...)N(pyridine) hydrogen bonding and these are connected into a double layer that stacks along the c-axis direction by C—H(...)π(pyridine) interactions
3D super-resolution deep-tissue imaging in living mice.
Stimulated emission depletion (STED) microscopy enables the three-dimensional (3D) visualization of dynamic nanoscale structures in living cells, offering unique insights into their organization. However, 3D-STED imaging deep inside biological tissue is obstructed by optical aberrations and light scattering. We present a STED system that overcomes these challenges. Through the combination of two-photon excitation, adaptive optics, red-emitting organic dyes, and a long-working-distance water-immersion objective lens, our system achieves aberration-corrected 3D super-resolution imaging, which we demonstrate 164 µm deep in fixed mouse brain tissue and 76 µm deep in the brain of a living mouse
Characteristics associated with quality of life among people with drug-resistant epilepsy
Quality of Life (QoL) is the preferred outcome in non-pharmacological trials, but there is little UK population evidence of QoL in epilepsy. In advance of evaluating an epilepsy self-management course we aimed to describe, among UK participants, what clinical and psycho-social characteristics are associated with QoL. We recruited 404 adults attending specialist clinics, with at least two seizures in the prior year and measured their self-reported seizure frequency, co-morbidity, psychological distress, social characteristics, including self-mastery and stigma, and epilepsy-specific QoL (QOLIE-31-P). Mean age was 42 years, 54% were female, and 75% white. Median time since diagnosis was 18 years, and 69% experienced ≥10 seizures in the prior year. Nearly half (46%) reported additional medical or psychiatric conditions, 54% reported current anxiety and 28% reported current depression symptoms at borderline or case level, with 63% reporting felt stigma. While a maximum QOLIE-31-P score is 100, participants’ mean score was 66, with a wide range (25–99). In order of large to small magnitude: depression, low self-mastery, anxiety, felt stigma, a history of medical and psychiatric comorbidity, low self-reported medication adherence, and greater seizure frequency were associated with low QOLIE-31-P scores. Despite specialist care, UK people with epilepsy and persistent seizures experience low QoL. If QoL is the main outcome in epilepsy trials, developing and evaluating ways to reduce psychological and social disadvantage are likely to be of primary importance. Educational courses may not change QoL, but be one component supporting self-management for people with long-term conditions, like epilepsy
Spatial Guilds in the Serengeti Food Web Revealed by a Bayesian Group Model
Food webs, networks of feeding relationships among organisms, provide
fundamental insights into mechanisms that determine ecosystem stability and
persistence. Despite long-standing interest in the compartmental structure of
food webs, past network analyses of food webs have been constrained by a
standard definition of compartments, or modules, that requires many links
within compartments and few links between them. Empirical analyses have been
further limited by low-resolution data for primary producers. In this paper, we
present a Bayesian computational method for identifying group structure in food
webs using a flexible definition of a group that can describe both functional
roles and standard compartments. The Serengeti ecosystem provides an
opportunity to examine structure in a newly compiled food web that includes
species-level resolution among plants, allowing us to address whether groups in
the food web correspond to tightly-connected compartments or functional groups,
and whether network structure reflects spatial or trophic organization, or a
combination of the two. We have compiled the major mammalian and plant
components of the Serengeti food web from published literature, and we infer
its group structure using our method. We find that network structure
corresponds to spatially distinct plant groups coupled at higher trophic levels
by groups of herbivores, which are in turn coupled by carnivore groups. Thus
the group structure of the Serengeti web represents a mixture of trophic guild
structure and spatial patterns, in contrast to the standard compartments
typically identified in ecological networks. From data consisting only of nodes
and links, the group structure that emerges supports recent ideas on spatial
coupling and energy channels in ecosystems that have been proposed as important
for persistence.Comment: 28 pages, 6 figures (+ 3 supporting), 2 tables (+ 4 supporting
Crystal structure 2-{[2-(3-phenylallylidene)hydrazin-1-yl]thiocarbonylsulfanylmethyl}pyridinium chloride
In the title salt of an S-substituted dithiocarbazate, C16H16N3S2+·Cl-, the dihedral angles between the almost planar (r.m.s deviation = 0.005 Å) central CN2S2 residue and the terminal pyridinium and phenyl rings are 80.09 (11) and 3.82 (11)°, respectively, indicating the cation has an L-shape; the amine H and thione S atoms are syn. The conformation about each of the imine [1.376 (3) Å] and ethene [1.333 (4) Å] bonds is E. The shortened C-C bond [1.444 (4) Å] linking the double bonds is consistent with conjugation in this part of the molecule. In the crystal, supramolecular layers with a jagged topology are formed by charged-assisted amine-H...Cl- and pyridinium-N+-H...Cl- hydrogen bonds. The layers stack along the a axis with no specific directional interactions between them
Is type II diabetes mellitus (NIDDM) a surgical disease?
Since February 1, 1980, 515 morbidly obese patients have undergone
the Greenville gastric bypass (GGB) operation. Of these,
212 (41.2%) were euglycemic, 288 (55.9%) were either diabetic
or had glucose intolerance, and 15 (2.9%) were unable to complete
the evaluation. After the operation, only 30 (5.8%) patients remained
diabetic (and 20 of these improved), 457 (88.7%) became
and have remained euglycemic, and inadequate data prevented
classification of the other 28 (5.4%). The patients who failed to
return to normal glucose values were older and their diabetes
was of longer duration than those who did. The effect of the
GGB was not only limited to the correction of abnormal glucose
levels. The GGB also corrected the abnormal levels of fasting
insulin and glycosylated hemoglobin in a cohort of 52 consecutive
severely obese patients with non-insulin-dependent diabetes. The
GGB effectively controls weight. If morbid obesity is defined as
100 pounds over ideal body weight, 89% of the patients are no
longer "morbidly" obese within 2 years. In most patients, the
control of the weight has been well maintained during the 11
years of follow-up; most of the upward creep in weight of 20.8%
between 24 and 132 months was from the 49 (9.5%) patients
who had staple line breakdowns between the large and small
gastric pouches. Non-insulin-dependent diabetes, previously
considered a chronic unrelenting disease, can be controlled in
the severely obese by the gastric bypass. Whether the correction
of glucose metabolism affects the complications of diabetes is
unknown. Whether the gastric bypass should be considered for
patients with advanced non-insulin-dependent diabetes but who
are not severely obese deserves consideration. The GGB has an
unacceptably high rate of staple line failure. Accordingly, the
authors have recently changed their procedure to one that divides
the stomach rather than partitions it with staples. Originally published Annals of Surgery, Vol. 215, No. 6, June 199
Australian recommendations on perioperative use of disease-modifying anti-rheumatic drugs in people with inflammatory arthritis undergoing elective surgery.
OnlinePublDisease-modifying antirheumatic drugs (DMARDs) are effective treatments for inflammatory arthritis but carry an increased risk of infection. For patients undergoing surgery there is a need to consider the trade-off between a theoretical increased risk of infection with continuation of DMARDs perioperatively versus an increased risk of disease flare if they are temporarily withheld. We used GRADE methodology to develop recommendations for perioperative use of DMARDs for people with inflammatory arthritis undergoing elective surgery. The recommendations form part of the NHMRC-endorsed Australian Living Guideline for the Pharmacological Management of Inflammatory Arthritis. Conditional recommendations were made against routinely discontinuing conventional synthetic (cs) and biologic (b) DMARDs in the perioperative period but to consider temporary discontinuation of bDMARDs in individuals with a high risk of infection or where the impact of infection would be severe. A conditional recommendation was made in favour of temporary discontinuation of targeted synthetic (ts) DMARDs in the perioperative period.Rachelle Buchbinder, Vanessa Glennon, Renea V. Johnston, Sue E. Brennan, Chris Fong, Suzie Edward May, Sean O, Neill, Peter Smitham, Lyndal Trevena, Glen Whittaker, Anita Wluka, and Samuel L. Whittl
LSST Science Book, Version 2.0
A survey that can cover the sky in optical bands over wide fields to faint
magnitudes with a fast cadence will enable many of the exciting science
opportunities of the next decade. The Large Synoptic Survey Telescope (LSST)
will have an effective aperture of 6.7 meters and an imaging camera with field
of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over
20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with
fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a
total point-source depth of r~27.5. The LSST Science Book describes the basic
parameters of the LSST hardware, software, and observing plans. The book
discusses educational and outreach opportunities, then goes on to describe a
broad range of science that LSST will revolutionize: mapping the inner and
outer Solar System, stellar populations in the Milky Way and nearby galaxies,
the structure of the Milky Way disk and halo and other objects in the Local
Volume, transient and variable objects both at low and high redshift, and the
properties of normal and active galaxies at low and high redshift. It then
turns to far-field cosmological topics, exploring properties of supernovae to
z~1, strong and weak lensing, the large-scale distribution of galaxies and
baryon oscillations, and how these different probes may be combined to
constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at
http://www.lsst.org/lsst/sciboo
Implementation of a Shared Data Repository and Common Data Dictionary for Fetal Alcohol Spectrum Disorders Research
Many previous attempts by fetal alcohol spectrum disorders researchers to compare data across multiple prospective and retrospective human studies have failed due to both structural differences in the collected data as well as difficulty in coming to agreement on the precise meaning of the terminology used to describe the collected data. Although some groups of researchers have an established track record of successfully integrating data, attempts to integrate data more broadly amongst different groups of researchers have generally faltered. Lack of tools to help researchers share and integrate data has also hampered data analysis. This situation has delayed improving diagnosis, intervention, and treatment before and after birth. We worked with various researchers and research programs in the Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CI-FASD) to develop a set of common data dictionaries to describe the data to be collected, including definitions of terms and specification of allowable values. The resulting data dictionaries were the basis for creating a central data repository (CI-FASD Central Repository) and software tools to input and query data. Data entry restrictions ensure that only data which conform to the data dictionaries reach the CI-FASD Central Repository. The result is an effective system for centralized and unified management of the data collected and analyzed by the initiative, including a secure, long-term data repository. CI-FASD researchers are able to integrate and analyze data of different types, collected using multiple methods, and collected from multiple populations, and data are retained for future reuse in a secure, robust repository
Central nervous system antiretroviral efficacy in HIV infection: a qualitative and quantitative review and implications for future research
<p>Abstract</p> <p>Background</p> <p>There is conflicting information as to whether antiretroviral drugs with better central nervous system (CNS) penetration (neuroHAART) assist in improving neurocognitive function and suppressing cerebrospinal fluid (CSF) HIV RNA. The current review aims to better synthesise existing literature by using an innovative two-phase review approach (qualitative and quantitative) to overcome methodological differences between studies.</p> <p>Methods</p> <p>Sixteen studies, all observational, were identified using a standard citation search. They fulfilled the following inclusion criteria: conducted in the HAART era; sample size > 10; treatment effect involved more than one antiretroviral and none had a retrospective design. The qualitative phase of review of these studies consisted of (i) a blind assessment rating studies on features such as sample size, statistical methods and definitions of neuroHAART, and (ii) a non-blind assessment of the sensitivity of the neuropsychological methods to HIV-associated neurocognitive disorder (HAND). During quantitative evaluation we assessed the statistical power of studies, which achieved a high rating in the qualitative analysis. The objective of the power analysis was to determine the studies ability to assess their proposed research aims.</p> <p>Results</p> <p>After studies with at least three limitations were excluded in the qualitative phase, six studies remained. All six found a positive effect of neuroHAART on neurocognitive function or CSF HIV suppression. Of these six studies, only two had statistical power of at least 80%.</p> <p>Conclusions</p> <p>Studies assessed as using more rigorous methods found that neuroHAART was effective in improving neurocognitive function and decreasing CSF viral load, but only two of those studies were adequately statistically powered. Because all of these studies were observational, they represent a less compelling evidence base than randomised control trials for assessing treatment effect. Therefore, large randomised trials are needed to determine the robustness of any neuroHAART effect. However, such trials must be longitudinal, include the full spectrum of HAND, ideally carefully control for co-morbidities, and be based on optimal neuropsychology methods.</p
- …