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The hippocampus, prefrontal cortex, and perirhinal cortex are critical to incidental order memory.
Considerable research in rodents and humans indicates the hippocampus and prefrontal cortex are essential for remembering temporal relationships among stimuli, and accumulating evidence suggests the perirhinal cortex may also be involved. However, experimental parameters differ substantially across studies, which limits our ability to fully understand the fundamental contributions of these structures. In fact, previous studies vary in the type of temporal memory they emphasize (e.g., order, sequence, or separation in time), the stimuli and responses they use (e.g., trial-unique or repeated sequences, and incidental or rewarded behavior), and the degree to which they control for potential confounding factors (e.g., primary and recency effects, or order memory deficits secondary to item memory impairments). To help integrate these findings, we developed a new paradigm testing incidental memory for trial-unique series of events, and concurrently assessed order and item memory in animals with damage to the hippocampus, prefrontal cortex, or perirhinal cortex. We found that this new approach led to robust order and item memory, and that hippocampal, prefrontal and perirhinal damage selectively impaired order memory. These findings suggest the hippocampus, prefrontal cortex and perirhinal cortex are part of a broad network of structures essential for incidentally learning the order of events in episodic memory
2,4-Diamino-6-methyl-1,3,5-triazin-1-ium hydrogen oxalate
The title compound, C4H8N5
+·C2HO4
−, was obtained from the reaction of oxalic acid and 2,4-diamino-6-methyl-1,3,5-triazine. The protonated triazine ring is essentially planar with a maximum deviation of 0.035 (1) Å, but the hydrogen oxalate anion is less planar, with a maximum deviation of 0.131 (1) Å for both carbonyl O atoms. In the crystal, the ions are linked by intermolecular N—H⋯O, N—H⋯N, O—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional network. Weak π–π [centroid–centroid distance = 3.763 Å] and C—O⋯π interactions [O⋯centroid = 3.5300 (16) Å, C—O⋯centroid = 132.19 (10)°] are also present
Rathat: A self-targeting printable brain implant system
There has not been a major change in how neuroscientists approach stereotaxic methods in decades. Here, we present a new stereotaxic method that provides an alternative approach to a traditional u-frame stereotaxic device and reduces costs, surgical time, and aids repeatability. The RatHat brain implantation system is a 3Dprintable stereotaxic device for rats that is fabricated prior to surgery and fits to the shape of the skull. RatHat builds are directly implanted into the brain without the need for head-leveling or coordinate-mapping during surgery. The RatHat can be used in conjunction with the traditional u-frame stereotaxic device, but does not require the use of a micromanipulator for successful implantations. Each RatHat contains several primary components including the implant for mounting intracranial components, the surgical stencil for targeting drill sites, and the protective cap for preventing damage from impacts and debris. Each component serves a unique function and can be used together or separately. We demonstrate the feasibility of the RatHat in four different proof-of-principle experiments: (1) a three-pole cannula apparatus, (2) an optrode-electrode assembly, (3) a fixed-electrode array, and (4) a tetrode hyperdrive. Implants were successful, durable, and long-lasting (up to nine months). RatHat print files are easily created, can be modified in computer aided design (CAD) software for a variety of applications, and are easily shared, contributing to open science goals and replications. The RatHat has been adapted to multiple experimental paradigms in our lab and should be a useful new way to conduct stereotaxic implant surgeries in rodents
Ethylenediaminium hemioxalate thiocyanate
In the title compound, C2H10N2
2+·0.5(C2O4)2−·NCS−, the ethylenediaminium dication adopts a (+)-synclinal conformation with an N—C—C—N torsion angle of 62.64 (15)°. The oxalate dianion lies across an inversion centre. In the crystal structure, the ions are linked through N—H⋯N, N—H⋯O and C—H⋯S hydrogen bonds, leading to the formation of a three-dimensional network
VLA Observations of J1228+441, a Luminous Supernova Remnant in NGC 4449
The luminous, oxygen-rich supernova remnant, J1228+441, is located in the
irregular galaxy NGC 4449 and has been observed at radio wavelengths for thirty
years. An analysis of recent VLA observations of NGC 4449, combined with VLA
archive data and previously published VLA and WSRT observations, yields light
curves at 6 and 20 cm from 1972 to 2002. The light curves at all radio
frequencies exhibit a marked decline in radio emission, confirming past
findings. This paper presents and discusses the radio light curves and spectral
index, alpha, variations from 1972 to 2002 where nu propto nu^(-alpha) and
compares J1228+441 with other radio supernovae. The spectral index of J1228+441
appears to have steepened in the last five years at higher frequencies from
alpha=0.64 +- 0.02 in 1996 to alpha=1.01 +- 0.02 in 2001-2002.Comment: aastex, 19 pages, 6 figures, to be published in A
Efficient low-loaded ternary Pd-In2O3-Al2O3 catalysts for methanol production
Pd-In2O3 catalysts are among the most promising alternatives to Cu-ZnO-Al2O3 for synthesis of CH3OH from CO2. However, the intrinsic activity and stability of In2O3 per unit mass should be increased to reduce the content of this scarcely available element and to enhance the catalyst lifetime. Herein, we propose and demonstrate a strategy for obtaining highly dispersed Pd and In2O3 nanoparticles onto an Al2O3 matrix by a one-step coprecipitation followed by calcination and activation. The activity of this catalyst is comparable with that of a Pd-In2O3 catalyst (0.52 vs 0.55 gMeOH h−1 gcat-1 at 300 \ub0C, 30 bar, 40,800 mL h−1 gcat-1) but the In2O3 loading decreases from 98 to 12 wt% while improving the long-term stability by threefold at 30 bar. In the new Pd-In2O3-Al2O3 system, the intrinsic activity of In2O3 is highly increased both in terms of STY normalized to In specific surface area and In2O3 mass (4.32 vs 0.56 g gMeOH h−1 gIn2O3-1 of a Pd- In2O3 catalyst operating at 300 \ub0C, 30 bar, 40,800 mL h−1 gcat-1).The combination of ex situ and in situ catalyst characterizations during reduction provides insights into the interaction between Pd and In and with the support. The enhanced activity is likely related to the close proximity of Pd and In2O3, wherein the H2 splitting activity of Pd promotes, in combination with CO2 activation over highly dispersed In2O3 particles, facile formation of CH3OH
Multidisciplinary teams, and parents, negotiating common ground in shared-care of children with long-term conditions: A mixed methods study
Background: Limited negotiation around care decisions is believed to undermine collaborative working between parents of children with long-term conditions and professionals, but there is little evidence of how they actually negotiate their respective roles. Using chronic kidney disease as an exemplar this paper reports on a multi-method study of social interaction between multidisciplinary teams and parents as they shared clinical care. Methods. Phases 1 and 2: a telephone survey mapping multidisciplinary teams' parent-educative activities, and qualitative interviews with 112 professionals (Clinical-psychologists, Dietitians, Doctors, Nurses, Play-specialists, Pharmacists, Therapists and Social-workers) exploring their accounts of parent-teaching in the 12 British children's kidney units. Phase 3: six ethnographic case studies in two units involving observations of professional/parent interactions during shared-care, and individual interviews. We used an analytical framework based on concepts drawn from Communities of Practice and Activity Theory. Results: Professionals spoke of the challenge of explaining to each other how they are aware of parents' understanding of clinical knowledge, and described three patterns of parent-educative activity that were common across MDTs: Engaging parents in shared practice; Knowledge exchange and role negotiation, and Promoting common ground. Over time, professionals had developed a shared repertoire of tools to support their negotiations with parents that helped them accomplish common ground during the practice of shared-care. We observed mutual engagement between professionals and parents where a common understanding of the joint enterprise of clinical caring was negotiated. Conclusions: For professionals, making implicit knowledge explicit is important as it can provide them with a language through which to articulate more clearly to each other what is the basis of their intuition-based hunches about parents' support needs, and may help them to negotiate with parents and accelerate parents' learning about shared caring. Our methodology and results are potentially transferrable to shared management of other conditions. © 2013 Swallow et al.; licensee BioMed Central Ltd
Prevalence of BRCA1 and BRCA2 pathogenic variants in a large, unselected breast cancer cohort.
Breast cancer patients with BRCA1/2-driven tumors may benefit from targeted therapy. It is not clear whether current BRCA screening guidelines are effective at identifying these patients. The purpose of our study was to evaluate the prevalence of inherited BRCA1/2 pathogenic variants in a large, clinically representative breast cancer cohort and to estimate the proportion of BRCA1/2 carriers not detected by selectively screening individuals with the highest probability of being carriers according to current clinical guidelines. The study included 5,122 unselected Swedish breast cancer patients diagnosed from 2001 to 2008. Target sequence enrichment (48.48 Fluidigm Access Arrays) and sequencing were performed (Illumina Hi-Seq 2,500 instrument, v4 chemistry). Differences in patient and tumor characteristics of BRCA1/2 carriers who were already identified as part of clinical BRCA1/2 testing routines and additional BRCA1/2 carriers found by sequencing the entire study population were compared using logistic regression models. Ninety-two of 5,099 patients with valid variant calls were identified as BRCA1/2 carriers by screening all study participants (1.8%). Only 416 study participants (8.2%) were screened as part of clinical practice, but this identified 35 out of 92 carriers (38.0%). Clinically identified carriers were younger, less likely postmenopausal and more likely to be associated with familiar ovarian cancer compared to the additional carriers identified by screening all patients. More BRCA2 (34/42, 81.0%) than BRCA1 carriers (23/50, 46%) were missed by clinical screening. In conclusion, BRCA1/2 mutation prevalence in unselected breast cancer patients was 1.8%. Six in ten BRCA carriers were not detected by selective clinical screening of individuals
Pan-Britain, mixed-methods study of multidisciplinary teams teaching parents to manage children's long-term kidney conditions at home: Study protocol
Background
Care of children and young people (children) with long-term kidney conditions is usually managed by multidisciplinary teams. Published guidance recommends that whenever possible children with long-term conditions remain at home, meaning parents may be responsible for performing the majority of clinical care-giving. Multidisciplinary team members, therefore, spend considerable time promoting parents' learning about care-delivery and monitoring care-giving. However, this parent-educative aspect of clinicians' role is rarely articulated in the literature so little evidence exists to inform professionals' parent-teaching interventions.
Methods
This ongoing study addresses this issue using a combination of quantitative and qualitative methods involving the twelve children's kidney units in England, Scotland and Wales. Phase I involves a survey of multidisciplinary team members' parent-teaching interventions using: i) A telephone-administered questionnaire to determine: the numbers of professionals from different disciplines in each team, the information/skills individual professionals relay to parents and the teaching strategies/interventions they use. Data will be managed using SPSS to produce descriptive statistics ii) Digitally-recorded, qualitative group or individual interviews with multidisciplinary team members to explore their accounts of the parent-teaching component of their role. Interviews will be transcribed anonymously and analysed using Framework Technique. Sampling criteria will be derived from analysis to identify one/two unit(s) for subsequent in-depth study Phase II involves six prospective, ethnographic case-studies of professional-parent interactions during parent-teaching encounters. Parents of six children with a long-term kidney condition will be purposively sampled according to their child's age, diagnosis, ethnicity and the clinical care-giving required; snowball sampling will identify the professionals involved in each case-study. Participants will provide signed consent; data gathering will involve a combination of: minimally-obtrusive observations in the clinical setting and families' homes; de-briefing interviews with participants to obtain views on selected interactions; focussed 'verbatim' field-notes, and case-note reviews. Data gathering will focus on communication between parents and professionals as parents learn care-giving skills and knowledge. Interviews will be digitally recorded and transcribed anonymously.
Discussion
This study involves an iterative-inductive approach and will provide a unique, detailed insight into the social context in which professionals teach and parents learn; it will inform professionals' parent-educative roles, educational curricula, and health care polic
A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction
The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function
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