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Vestibular schwannoma is the most common neoplasm in the cerebellopontine angle, and fast spin-echo T2-weighted magnetic resonance imaging is the most sensitive test for diagnosing it. This study evaluated the financial and time costs of unnecessary magnetic resonance imaging referrals before and after the application of a magnetic resonance imaging protocol.
A full audit cycle was used for the assessment. The first cycle in January 2012 was retrospective and evaluated the financial impact of current selection criteria for magnetic resonance imaging referral against standard guidelines. The second cycle in January 2014 was prospective after implementation of the protocol.
There were 46 and 112 patients who had magnetic resonance imaging during first and second cycle, respectively. Of the referrals for magnetic resonance imaging, 65 per cent versus 81 per cent of the referrals were appropriate in the first and second cycles, respectively. The relative risk was reduced from 0.5 to 0.2. The waiting times for magnetic resonance imaging scans improved.
Selection criteria for magnetic resonance imaging referral are important in reducing waiting times for scans, patient anxiety and conserving trust resources.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Visual homing is a local navigation technique used to direct a robot to a previously seen location by comparing the image of the original location with the current visual image. Prior work has shown that exploiting depth cues such as image scale or stereo-depth in homing leads to improved homing performance. While it is not unusual to use a panoramic field of view (FOV) camera in visual homing, it is unusual to have a panoramic FOV stereo-camera. So, while the availability of stereo-depth information may improve performance, the concomitant-restricted FOV may be a detriment to performance, unless specialized stereo hardware is used. In this paper, we present an investigation of the effect on homing performance of varying the FOV widths in a stereo-vision-based visual homing algorithm using a common stereo-camera. We have collected six stereo-vision homing databases – three indoor and three outdoor. Based on over 350,000 homing trials, we show that while a larger FOV yields performance improvements for larger homing offset angles, the relative improvement falls off with increasing FOVs, and in fact decreases for the widest FOV tested. We conduct additional experiments to identify the cause of this fall-off in performance, which we term the ‘blinder’ effect, and which we predict should affect other correspondence-based visual homing algorithms.
Background: There is growing concern about emergency physicians overuse of computed tomography (CT). In an attempt to ensure appropriate ordering many hospitals implement strict protocols for ordering of CT scans in the emergency department (ED) that include approval of all scans by a board-certified radiologist, and a reduced access to CT overnight. Aim Statement: The aim of this study is to review the impact of RAD ED – direct access to CT ordering by ED physicians, 24hr CT technologist and third-party reporting on CT scans overnight. Our objectives were to assess the effect on; 1) ED length of stay, 2) number of CT scans ordered and 3) admission rates. Measures & Design: We conducted a prospective pilot before & after study at a single tertiary-care emergency department between February 1st, 2018 and July 31st, 2018. Inclusion criteria were adult patients presenting to the emergency department and undergoing CT for any of the following: face, neck, spine, upper and lower extremities, chest, abdomen and pelvis. Exclusion criteria were those undergoing CT head for stroke or trauma. Evaluation/Results: A total of 924 patients met our criteria, 352 before and 568 after implementation. Comparison of the patient populations demonstrate very similar characteristics in both groups; (49% male, average age 56 years, CTAS 2(40%) and 3(47%). Results demonstrate that an additional 216 scans were performed in post-implementation group. This equates to an increase of 61%. ED length of stay averaged 5.6 hours pre-implementation and 4.7 hours post-implementation. This corresponds to a significant reduction in length of stay of approximately 0.9 hours (p < 0.01). Collection is currently ongoing for factors that we will adjust for a multivariate analysis, including admission rates. Discussion/Impact: RAD ED led to a significant increase in CT ordering and decrease in ED length of stay. We believe that this project provides important information to clinicians and patients with regards to overall CT utilization, ED wait times, follow up visits for CT scanning and admission rates. It is also important for administrators to help decide if these new rules are leading to improved efficiency, and to help estimate their financial impact.
In the USA, western Washington (WWA) and the Alaska (AK) Interior are two regions where maritime and continental climates, high latitude and cropping systems necessitate early maturing spring wheat (Triticum aestivum L.). Both regions aim to increase the production of hard spring bread wheat for human consumption to support regional agriculture and food systems. The Nordic region of Europe has a history of breeding for early maturing spring wheat and also experiences long daylengths with mixed maritime and continental climates. Nordic wheat also carries wildtype (wt) NAM-B1, an allele associated with accelerated senescence and increased grain protein and micronutrient content, at a higher frequency than global germplasm. Time to senescence, yield, protein and mineral content were evaluated on 42 accessions of Nordic hard red spring wheat containing wt NAM-B1 over 2 years on experimental stations in WWA and the AK Interior. Significant variation was found by location and accession for time to senescence, suggesting potential parental lines for breeding programmes targeting early maturity. Additionally, multiple regression analysis showed that decreased time to senescence correlated negatively with grain yield and positively with grain protein, iron and zinc content. Breeding for early maturity in these regions will need to account for this potential trade-off in yield. Nordic wt NAM-B1 accessions with early senescence yet with yields similar to regional checks are reported. Collaboration among alternative wheat regions can aid in germplasm exchange and varietal development as shown here for the early maturing trait.
The impact of dementia-related stressors and strains have been examined for their potential to threaten the well-being of either the person with dementia or the family care partner, but rarely have studies considered the dyadic nature of well-being in dementia. The purpose of this study was to examine the dyadic effects of multiple dimensions of strain on the well-being of dementia care dyads.
Using multilevel modeling to account for the inter-relatedness of individual well-being within dementia care dyads, we examined cross-sectional responses collected from 42 dyads comprised of a hospitalized patient diagnosed with a primary progressive dementia (PWD) and their family care partner (CP). Both PWDs and CPs self-reported on their own well-being using measures of quality of life (QOL-Alzheimer’s Disease scale) and depressive symptoms (Center for Epidemiological Studies Depression Scale).
In adjusted models, the PWD’s well-being (higher QOL and lower depressive symptoms) was associated with significantly less strain in the dyad’s relationship. The CP’s well-being was associated with significantly less care-related strain and (for QOL scale) less relationship strain.
Understanding the impact of dementia on the well-being of PWDs or CPs may require an assessment of both members of the dementia care dyad in order to gain a complete picture of how dementia-related stressors and strains impact individual well-being. These results underscore the need to assess and manage dementia-related strain as a multi-dimensional construct that may include strain related to the progression of the disease, strain from providing care, and strain on the dyad’s relationship quality.
Successful organic farming requires crop varieties that are resilient to environmental variability. Assessing variety performance across the range of conditions represented on working farms is vital to developing such varieties; however, data collected from on-farm, participatory trials can be difficult to both collect and interpret. To assess the utility of data arising from participatory trialing efforts, we examined the performance of butternut squash (Cucurbita moschata L.), broccoli (Brassica oleracea L.) and carrot (Daucus carota L.) varieties grown in diverse organic production environments in participatory trials in Oregon, Washington, Wisconsin and New York using adaptability analysis (regression of variety means on environmental index). Patterns of adaptation varied across varieties, with some demonstrating broad adaptation and others showing specific adaptation to low- or high-yielding environments. Selection of varieties with broad vs specific adaptation should be guided by farmers’ risk tolerance and on-farm environmental variation. Adaptability analysis was appropriate for continuous variables (e.g., yield traits), but less so for ordinal variables and quality traits such as flavor and appearance, which can be vitally important in organic vegetable crop variety selection. The relative advantages of adaptability analysis and additive main effects and multiplicative interactions are also discussed in relation to on-farm trial networks. This work demonstrated the unique challenges presented by extensive participatory vegetable trialing efforts, which, as compared to grain crops, require novel approaches to facilitating farmer participation as well as data collection and analysis. Efficient, precise and reliable methods for evaluating quality related traits in these crops would allow researchers to assess stability and adaptation across a wider range of traits, providing advantages for effective plant breeding and trialing activities within the organic sector.
We present an indentation-scope that interfaces with confocal microscopy, enabling direct observation of the three-dimensional (3D) microstructural response of coatings on substrates. Using this method, we compared microns-thick polymer coatings on glass with and without silica nanoparticle filler. Bulk force data confirmed the >30% modulus difference, while microstructural data further revealed slip at the glass-coating interface. Filled coatings slipped more and about two times faster, as reflected in 3D displacement and von Mises strain fields. Overall, these data indicate that silica-doping of coatings can dramatically alter adhesion. Moreover, this method compliments existing theoretical and modeling approaches for studying indentation in layered systems.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
The 2001/02 austral summer was the warmest summer on record in Taylor Valley, Antarctica, (∼78° S) since continuous records of temperature began in 1985. The highest stream-flows ever recorded in the Onyx River, Wright Valley, were also recorded that year (the record goes back to the 1969/70 austral summer). In early January 2002, a groundwater seep was observed flowing in the southwest portion of Taylor Valley. This flow has been named ‘Wormherder Creek’ (WHC) and represents an unusual event, probably occurring on a decadal time-scale. The physical characteristics of this feature suggest that it may have flowed at other times in the past. Other groundwater seeps, emanating from the north-facing slope of Taylor Valley, were also observed. Little work has been done previously on these very ephemeral seeps, and the source of water is unknown. These features, resembling recently described features on Mars, represent the melting of subsurface ice. The Martian features have been interpreted as groundwater seeps. In this paper we compare the chemistry of the WHC groundwater seep to that of the surrounding streams that flow every austral summer. The total dissolved solids content of WHC was ∼6 times greater than that of some nearby streams. The Na : Cl and SO4 : Cl ratios of the seep waters are higher than those of the streams, but the Mg : Cl and HCO3 : Cl ratios are lower, indicating different sources of solutes to the seeps compared to the streams. The enrichment of Na and SO4 relative to Cl may suggest significant dissolution of mirabilite within the previously unwetted soil. The proposed occurrence of abundant mirabilite in higher-elevation soils of the dry valley region agrees with geochemical models developed, but not tested, in the late 1970s. The geochemical data demonstrate that these seeps could be important in ‘rinsing’ the soils by dissolving and redistributing the long-term accumulation of salts, and perhaps improving habitat suitability for soil biota. The H4SiO4 concentration is 2–3 times greater in WHC than in the surrounding streams, indicating a large silicate-weathering component in the seep waters.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
Objectives: Sleep quality affects memory and executive function in older adults, but little is known about its effects in midlife. If it affects cognition in midlife, it may be a modifiable factor for later-life functioning. Methods: We examined the association between sleep quality and cognition in 1220 middle-aged male twins (age 51–60 years) from the Vietnam Era Twin Study of Aging. We interviewed participants with the Pittsburgh Sleep Quality Index and tested them for episodic memory as well as executive functions of inhibitory and interference control, updating in working memory, and set shifting. Interference control was assessed during episodic memory, inhibitory control during working memory, and non-memory conditions and set shifting during working memory and non-memory conditions. Results: After adjusting for covariates and correcting for multiple comparisons, sleep quality was positively associated with updating in working memory, set shifting in the context of working memory, and better visual-spatial (but not verbal) episodic memory, and at trend level, with interference control in the context of episodic memory. Conclusions: Sleep quality was associated with visual-spatial recall and possible resistance to proactive/retroactive interference. It was also associated with updating in working memory and with set shifting, but only when working memory demands were relatively high. Thus, effects of sleep quality on midlife cognition appear to be at the intersection of executive function and memory processes. Subtle deficits in these age-susceptible cognitive functions may indicate increased risk for decline in cognitive abilities later in life that might be reduced by improved midlife sleep quality. (JINS, 2018, 24, 67–76)
The unique phenotypic and genetic aspects of obsessive-compulsive (OCD) and attention-deficit/hyperactivity disorder (ADHD) among individuals with Tourette syndrome (TS) are not well characterized. Here, we examine symptom patterns and heritability of OCD and ADHD in TS families.
OCD and ADHD symptom patterns were examined in TS patients and their family members (N = 3494) using exploratory factor analyses (EFA) for OCD and ADHD symptoms separately, followed by latent class analyses (LCA) of the resulting OCD and ADHD factor sum scores jointly; heritability and clinical relevance of the resulting factors and classes were assessed.
EFA yielded a 2-factor model for ADHD and an 8-factor model for OCD. Both ADHD factors (inattentive and hyperactive/impulsive symptoms) were genetically related to TS, ADHD, and OCD. The doubts, contamination, need for sameness, and superstitions factors were genetically related to OCD, but not ADHD or TS; symmetry/exactness and fear-of-harm were associated with TS and OCD while hoarding was associated with ADHD and OCD. In contrast, aggressive urges were genetically associated with TS, OCD, and ADHD. LCA revealed a three-class solution: few OCD/ADHD symptoms (LC1), OCD & ADHD symptoms (LC2), and symmetry/exactness, hoarding, and ADHD symptoms (LC3). LC2 had the highest psychiatric comorbidity rates (⩾50% for all disorders).
Symmetry/exactness, aggressive urges, fear-of-harm, and hoarding show complex genetic relationships with TS, OCD, and ADHD, and, rather than being specific subtypes of OCD, transcend traditional diagnostic boundaries, perhaps representing an underlying vulnerability (e.g. failure of top-down cognitive control) common to all three disorders.
All medical procedures, be they therapeutic or investigative, touch on the issue of consent – that is a measure of willingness on the part of the patient to undertake the procedure proposed. In this, ECT is no different to other therapeutic interventions. However, ECT has a particular status both within psychiatry and within the law that makes specific discussion of issues with regard to consent necessary.
General issues regarding consent
Electroconvulsive therapy is unusual in that consent obtained is for a course of treatments rather than for an individual procedure. It is also customary that the person seeking the consent will not be the person giving the treatment. The fact that the person receiving treatment has a psychiatric disorder sufficiently severe for ECT to be considered raises questions about their capacity; this makes it particularly important that consent is properly obtained and valid. It is unlawful and unethical to treat a patient who is capable of understanding the nature of any procedure, its purpose and implications, the anticipated benefits and any reasonably foreseeable adverse effects without first explaining it. The patient must then agree. Even if patients choose not to be informed of the full details of their diagnosis and treatment, they must be given the option of receiving this information. Guidance on good practice in consent can be found in publications from the Department of Health in England and Wales (2009), the Department of Health, Social Services and Public Safety in Northern Ireland (2003) and the Scottish Executive (2006), as well as from the General Medical Council (2008).
Obtaining valid consent should be considered a process rather than an event and it is necessary for patients to be given an adequate length of time to consider the benefits and drawbacks of the proposed treatment before making an informed decision. Patients should be informed of the risks and unwanted effects of ECT (Chapters 7–9) and they need to realise that a general anaesthetic is involved. If there are specific anaesthetic risks, the anaesthetist should explain these and obtain the necessary consent.
It is helpful for patients and carers to be provided with information obtained from different sources. Written information sheets may be useful (e.g. Appendix V); these need to be accompanied by the opportunity to discuss issues with members of the therapeutic team, family members, carers, advocates, etc.
Spectral analysis of time series of a c. 17 ± 0.3 year core, calibrated for total ß activity recovered from Sentik Glacier (4908m) Ladakh, Himalaya, yields several recognizable periodicities including subannual, annual, and multi-annual. The time-series, include both chemical data (chloride, sodium, reactive iron, reactive silicate, reactive phosphate, ammonium, δD, δ(18O) and pH) and physical data (density, debris and ice-band locations, and microparticles in size grades 0.50 to 12.70 μm). Source areas for chemical species investigated and general air-mass circulation defined from chemical and physical time-series are discussed to demonstrate the potential of such studies in the development of paleometeorological data sets from remote high-alpine glacierized sites such as the Himalaya.
The production of climatic-change records using glaciochemical time series has seen minimal application in the Transantarctic Mountains. This is true despite the fact that glacial geologic studies in this area are the primary basis for understanding the glacial history of East Antarctica and thus provide an excellent potential framework for the more detailed records obtainable from glaciochemical studies. Numerous sites within the Transantarctic Mountains fit the requirements necessary for the retrieval of ice cores, and pilot studies have been conducted in both southern Victoria Land (Mayewski and Lyons 1982) and northern Victoria Land (Allen and others 1985). These pilot studies have validated the hypothesis that glaciochemical records retrieved from appropriately chosen ice-core sites in the Transantarctic Mountains can be used for: (1) assessing the current stability of the East Antarctic ice sheet, (2) validating models concerning the recent glacial history of the Transantarctic Mountains, (3) searching for relatively high-frequency (1–100 year) climatic signals, (4) determining changes in the relative geography (ocean – land – ice) of a region, and (5) defining the relative importance of the chemical species source areas (i.e. volcanic, biogenic, anthropogenic, marine, crustal) that provide precipitation to the Transantarctic Mountains.
During the 1984–85 austral summer, a combined University of New Hampshire – Polar Ice Coring Office effort resulted in the recovery of a 201 m long core from a 2800 m high snow massif atop the Dominion Range (85°15'S, 166°10'E), close to the confluence of the Mill and Beardmore glaciers. Chemical and physical data sets to be developed from this ice core, which is estimated to span a period of approximately 1000 years, include: a detailed 6 m snow pit, several shallow snow pits, and fresh and aged surface snow, in combination with a radio echo-sounding survey of the general area, which will be used to provide three-dimensional control. Chemical and physical analyses conducted as part of the study include: stratigraphy, density, sulfate, nitrate, fluoride, chloride, phosphate, sodium, reactive silicate, total beta activity and oxygen isotopes. The oxygen-isotope analyses are being provided by P. Grootes and M. Stuiver (University of Washington), and all other analyses are being conducted by the Glacier Research Group (University of New Hampshire).