Did private election administration funding advantage Democrats in 2020?

Private donors contributed more than $350 million to local election officials to support the administration of the 2020 election. Supporters argue these grants were neutral and necessary to maintain normal election operations during the pandemic, while critics worry these grants mostly went to Democratic strongholds and tilted election outcomes. How much did these grants shape the 2020 presidential election? To answer this question, we collect administrative data on private election administration grants and election outcomes. We then use advances in synthetic control methods to compare presidential election results and turnout in counties that received grants to counties with similar election results and turnout before 2020. While Democratic counties were more likely to apply for a grant, we find that the grants did not have a noticeable effect on the presidential election. Our estimates of the average effect on Democratic vote share range from 0.03 to 0.36 percentage points. Our estimates of the average effect of receiving a grant on turnout range from 0.03 to 0.14 percentage points. Across specifications, our 95% CIs typically include negative effects and all fail to include effects on Democratic vote share larger than 0.58 percentage points and effects on turnout larger than 0.40 percentage points. We characterize the magnitude of our effects by asking how large they are compared to the margin by which Biden won the 2020 election. In simple bench-marking exercises, we find that the effects of the grants were likely too small to have changed the outcome of the 2020 presidential election.

Surgical recovery from the COVID-19 pandemic in English adult neurosurgical centres.

OBJECTIVES: The COVID-19 pandemic required a change in resource priority from Neurosurgical care in order to treat medically unwell patients suffering from the complications of COVID-19 infections. We demonstrate the impact of COVID-19 on total bed days in 24 Neurosurgical centres in England offering adult Neurosurgery as well as the total spells (single inpatient episodes) for operative Neurosurgical patients between 2020 and 2022 when compared with 2019. METHODS: We used Capse Healthcare Knowledge System software iCompare in order to show the change in total spells for patients undergoing a primary or secondary Neurosurgical procedure as defined using the National Neurosurgical Audit Programme (NNAP) OPCS-4 coding framework between 2019 and 2022. RESULTS: The overall mortality rate of COVID-19 patients was 12.3% and the percentage of total bed days taken up by COVID-19 patients in hospitals at large was on average 7.7%. The total number of spells for all procedures over the 24 centres in 2022 was 39,019 compared with 45,742 in 2019. There was a cumulative deficit of 24,904 spells. The loss of spells was not equally distributed across regions and hospital Trusts. The average number of referral to treatment pathways completed within 18 weeks has declined from 76% to 57% over the study period and the referral to treatment clearance time has risen from 17 to 24 weeks. CONCLUSIONS: The mean elective cranial output in 2022 compared with 2019 is at 88% with spinal output lagging at 69%. If the rate of change year on year were to remain at current levels then we would reach pre-pandemic levels of output by 2026.

Evidence for density-dependent effects on body composition of a large omnivore in a changing Greater Yellowstone Ecosystem.

Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance-density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance-density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 1758) in the Greater Yellowstone Ecosystem, with estimates of body composition (lean body mass and percent body fat) serving as indicators of individual performance over two decades (2000-2020) during which time pronounced environmental changes have occurred. Several high-calorie foods for grizzly bears have mostly declined in recent decades (e.g., whitebark pine [Pinus albicaulis, Engelm, 1863]), while increasing human impacts from recreation, development, and long-term shifts in temperatures and precipitation are altering the ecosystem. We hypothesized that individual lean body mass declines as population density increases (H1), and that this effect would be more pronounced among growing individuals (H2). We also hypothesized that omnivory helps grizzly bears buffer energy intake from changing foods, with body fat levels being independent from population density and environmental changes (H3). Our analyses showed that individual lean body mass was negatively related to population density, particularly among growing-age females, supporting H1 and partially H2. In contrast, population density or sex had little effect on body fat levels and rate of accumulation, indicating that sufficient food resources were available on the landscape to accommodate successful use of shifting food sources, supporting H3. Our results offer important insights into ecological feedback mechanisms driving individual performances within a population undergoing demographic and ecosystem-level changes. However, synergistic effects of continued climate change and increased human impacts could lead to more extreme changes in food availability and affect observed population resilience mechanisms. Our findings underscore the importance of long-term studies in protected areas when investigating complex ecological relationships in an increasingly anthropogenic world.

Epidemiology and Outcomes of Peripheral and Non-Aortocaval Vascular Trauma in Scotland 2011 - 2018.

OBJECTIVE: This population based study aimed to examine the demographics, mechanisms, and outcomes of patients in Scotland suffering peripheral and non-aortocaval vascular trauma between 2011 and 2018. METHODS: A retrospective observational study was conducted using prospectively collected data derived from the Scottish Trauma Audit Group (STAG) from 1 January 2011 to 31 December 2018. Peripheral and non-aortocaval vascular trauma patients were identified using Abbreviated Injury Severity (AIS) codes. Demographics, mechanisms, types of injury, severity, and outcomes were analysed. RESULTS: Of 30 831 patients admitted with trauma to Scottish hospitals, 569 (1.8%) patients suffered a vascular injury during the eight year study period with 275 (0.9%) patients sustaining a peripheral or non-aortocaval vascular injury. There were 221 (80%) men and 54 (20%) women with a median (range) age of 39 (14 - 88) years. Blunt trauma was responsible for 179 (65%) injuries, of which road traffic accidents were the most common mechanism. A further 67 (24%) injuries were due to penetrating trauma, of which assault was the most common cause. The most common injury was to abdominal arteries (e.g., hepatic, renal, splenic [n = 83]) with an associated mortality rate of 17%. The median (range) Injury Severity Score (ISS) was 16 (4 - 75). Sixteen (6%) patients died in the Emergency Department (ED). Two hundred and twenty-seven (83%) patients were taken to theatre during their admission with a 30 day peri-operative mortality rate of 10%, compared with an overall mortality rate of 16%. Injuries to an abdominal vein (e.g., portal, renal, splenic, superior mesenteric) had the highest number of associated deaths, with 11 (32%) of 34 cases resulting in a fatality. CONCLUSION: There is a low incidence of vascular trauma in Scotland. Blunt force was responsible for more vascular injuries than penetrating trauma. Patients with peripheral and non-aortocaval vascular injuries are likely to be severely injured and suffer a high mortality rate.

Universal vote-by-mail has no impact on partisan turnout or vote share.

In response to coronavirus disease 2019 (COVID-19), many scholars and policy makers are urging the United States to expand voting-by-mail programs to safeguard the electoral process. What are the effects of vote-by-mail? In this paper, we provide a comprehensive design-based analysis of the effect of universal vote-by-mail-a policy under which every voter is mailed a ballot in advance of the election-on electoral outcomes. We collect data from 1996 to 2018 on all three US states that implemented universal vote-by-mail in a staggered fashion across counties, allowing us to use a difference-in-differences design at the county level to estimate causal effects. We find that 1) universal vote-by-mail does not appear to affect either party's share of turnout, 2) universal vote-by-mail does not appear to increase either party's vote share, and 3) universal vote-by-mail modestly increases overall average turnout rates, in line with previous estimates. All three conclusions support the conventional wisdom of election administration experts and contradict many popular claims in the media.

Fur: Find unique genomic regions for diagnostic PCR.

MOTIVATION: Unique marker sequences are highly sought after in molecular diagnostics. Nevertheless, there are only few programs available to search for marker sequences, compared to the many programs for similarity search. We therefore wrote the program Fur for Finding Unique genomic Regions. RESULTS: Fur takes as input a sample of target sequences and a sample of closely related neighbors. It returns the regions present in all targets and absent from all neighbors. The recently published program genmap can also be used for this purpose and we compared it to fur. When analyzing a sample of 33 genomes representing the major phylogroups of E.coli, fur was 40 times faster than genmap but used three times more memory. On the other hand, genmap yielded three times more markers, but they were less accurate when tested in silico on a sample of 237 E.coli genomes. We also designed phylogroup-specific PCR primers based on the markers proposed by genmap and fur, and tested them by analyzing their virtual amplicons in GenBank. Finally, we used fur to design primers specific to a Lactobacillus species, and found excellent sensitivity and specificity in vitro. AVAILABILITY AND IMPLEMENTATION: Fur sources and documentation are available from https://github.com/evolbioinf/fur. The compiled software is posted as a docker container at https://hub.docker.com/r/haubold/fox. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Risky business: How an herbivore navigates spatiotemporal aspects of risk from competitors and predators.

Understanding factors that influence animal behavior is central to ecology. Basic principles of animal ecology imply that individuals should seek to maximize survival and reproduction, which means carefully weighing risk against reward. Decisions become increasingly complex and constrained, however, when risk is spatiotemporally variable. We advance a growing body of work in predator-prey behavior by evaluating novel questions where a prey species is confronted with multiple predators and a potential competitor. We tested how fine-scale behavior of female mule deer (Odocoileus hemionus) during the reproductive season shifted depending upon spatial and temporal variation in risk from predators and a potential competitor. We expected female deer to avoid areas of high risk when movement activity of predators and a competitor were high. We used GPS data collected from 76 adult female mule deer, 35 adult female elk, 33 adult coyotes, and six adult mountain lions. Counter to our expectations, female deer exhibited selection for multiple risk factors, however, selection for risk was dampened by the exposure to risk within home ranges of female deer, producing a functional response in habitat selection. Furthermore, temporal variation in movement activity of predators and elk across the diel cycle did not result in a shift in movement activity by female deer. Instead, the average level of risk within their home range was the predominant factor modulating the response to risk by female deer. Our results counter prevailing hypotheses of how large herbivores navigate risky landscapes and emphasize the importance of accounting for the local environment when identifying effects of risk on animal behavior. Moreover, our findings highlight additional behavioral mechanisms used by large herbivores to mitigate multiple sources of predation and potential competitive interactions.

Paediatric Cavernous Malformation of the Trigeminal Nerve: Case Report and Review of the Literature.

INTRODUCTION: Intradural, extra-axial cerebral cavernous malformations (CCMs) are rare entities and are mostly reported in relation to the optic apparatus or the facial/vestibulocochlear complex. Cranial nerve CCMs tend to follow a clinically aggressive course, with a tendency to progressive neurological dysfunction following intra-lesional haemorrhage or less commonly due to the effects of subarachnoid haemorrhage. CASE PRESENTATION: We report the first case of a trigeminal CCM presenting in a child with otalgia and left-sided headaches. The patient was initially managed with radiological surveillance but required surgical management following deterioration. We describe the successful treatment of the lesion with microsurgical resection. CONCLUSION: A CCM should be considered in the differential diagnosis of mass lesions arising in the region of the trigeminal nerve. Surgical resection is recommended to prevent neurological deterioration and may result in significant symptomatic improvement.

Post-operative tension spinal subdural extra-arachnoid hygroma of the lumbar spine: case series, literature review, and recommendations for clinical management.

OBJECTIVE: Case series presentation and literature review of patient group suffering from symptomatic tension subdural extra-arachnoid hygroma following decompressive surgery for degenerative lumbar stenosis or disc disease. The purpose was to better understand this rare post-operative complication with a pathognomic radiological sign to help recommend optimal strategies for clinical management. METHODS: Retrospective case series comprising seven cases from one tertiary Neurosurgical centre spanning a 10-year period from 2011 to 2021. Patients included were those known to have undergone a spinal procedure and subsequently to have developed a symptomatic spinal subdural extra-arachnoid hygroma (SSEH). A literature review was conducted using PubMed, MEDLINE and EMBASE (keywords 'subdural hygroma', 'lumbar CSF hygroma', 'extra arachnoid hygroma', 'extra-arachnoid CSF collection', 'CSF tension hygroma', 'lumbar extra arachnoid hygroma', 'lumbar spinal hygroma', 'post-operating spinal hygroma', 'post-operative spinal CSF collection') and through reading references cited in relevant articles. Articles involving post-operative SSEH following lumbar spinal surgery were included. RESULTS: Rare complication with only five other cases in the literature. Dural breach described intra-operatively in only 5 of 12 total cases from our series and the literature. 5 patients in our series were managed surgically with 2 being managed conservatively. All patients in our series improved symptomatically and radiologically following surgical or conservative management. CONCLUSIONS: This is a rare post-lumbar surgery complication that can cause rapidly deteriorating lower limb and sphincteric function. Surgical management with wide durotomy and arachnoid marsupialisation can lead to reversal of neurological deterioration and excellent clinical results. A delayed presentation with pseudomeningocele formation may be managed conservatively if neurology is stable or improving. It is a condition that it is important for the clinician to recognise in order to instigate appropriate management in a time-dependent fashion.

Reintroduced wolves and hunting limit the abundance of a subordinate apex predator in a multi-use landscape.

Top-down effects of apex predators are modulated by human impacts on community composition and species abundances. Consequently, research supporting top-down effects of apex predators occurs almost entirely within protected areas rather than the multi-use landscapes dominating modern ecosystems. Here, we developed an integrated population model to disentangle the concurrent contributions of a reintroduced apex predator, the grey wolf, human hunting and prey abundances on vital rates and abundance of a subordinate apex predator, the puma. Increasing wolf numbers had strong negative effects on puma fecundity, and subadult and adult survival. Puma survival was also influenced by density dependence. Overall, puma dynamics in our multi-use landscape were more strongly influenced by top-down forces exhibited by a reintroduced apex predator, than by human hunting or bottom-up forces (prey abundance) subsidized by humans. Quantitatively, the average annual impact of human hunting on equilibrium puma abundance was equivalent to the effects of 20 wolves. Historically, wolves may have limited pumas across North America and dictated puma scarcity in systems lacking sufficient refugia to mitigate the effects of competition.

Redefining physiological responses of moose (Alces alces) to warm environmental conditions.

We tested the concept that moose (Alces alces) begin to show signs of thermal stress at ambient air temperatures as low as 14 °C. We determined the response of Alaskan female moose to environmental conditions from May through September by measuring core body temperature, heart rate, respiration rate, rate of heat loss from exhaled air, skin temperature, and fecal and salivary glucocorticoids. Seasonal and daily patterns in moose body temperature did not passively follow the same patterns as environmental variables. We used large changes in body temperature (≥1.25 °C in 24hr) to indicate days of physiological tolerance to thermal stressors. Thermal tolerance correlated with high ambient air temperatures from the prior day and with seasonal peaks in solar radiation (June), ambient air temperature and vapor pressure (July). At midday (12:00hr), moose exhibited daily minima of body temperature, heart rate and skin temperature (difference between the ear artery and pinna) that coincided with daily maxima in respiration rate and the rate of heat lost through respiration. Salivary cortisol measured in moose during the morning was positively related to the change in air temperature during the hour prior to sample collection, while fecal glucocorticoid levels increased with increasing solar radiation during the prior day. Our results suggest that free-ranging moose do not have a static threshold of ambient air temperature at which they become heat stressed during the warm season. In early summer, body temperature of moose is influenced by the interaction of ambient temperature during the prior day with the seasonal peak of solar radiation. In late summer, moose body temperature is influenced by the interaction between ambient temperature and vapor pressure. Thermal tolerance of moose depends on the intensity and duration of daily weather parameters and the ability of the animal to use physiological and behavioral responses to dissipate heat loads.

Additional qualifications of trainees in specialist training programs in Australia.

BACKGROUND: In Australia, the number of medical graduates per year has increased at a greater rate than the increase in the number of specialist training places. Consequently, competition for training positions is intensifying. There is anecdotal evidence to suggest that medical graduates are acquiring additional qualifications to compete with their peers Stevenson 2017 ( https://insightplus.mja.com.au/2017/36/specialty-training-places-the-other-looming-crisis/ ). Our study investigates this phenomenon of additional credentialing and demonstrates the number and type of postgraduate and research qualifications obtained by specialists in training in Australia. This is the first study to assess the number and type of credentials acquired by registrars in each specialty and to provide insight into differences between specialities. METHODS: Information on specialists in training was obtained through the Medicine in Australia: Balancing Employment and Life (MABEL) survey conducted between 2008 and 2014. The number of any additional qualifications and specific PhD, Master's degree, postgraduate diploma/certificate and research degrees from medical school were assessed for each specialist training scheme in the database. RESULTS: Overall, 995 registrars representing 13 specialties were included. Just under a third (30.4%) completed a research-based degree during their medical degree and almost half (46.7%) of specialist registrars obtained further qualifications after completing medicine. A significantly higher proportion of ophthalmology (78.6%) and paediatric (67.5%) registrars, and a lower percentage of emergency medicine (36.7%) registrars, held postgraduate qualifications. Overall, 2.4% of registrars held a PhD and 10.1% held a Master's degree. A higher percentage of either PhD or Master's was held by ophthalmology (64.3%) and surgical (30.6%) trainees and a lower percentage by anaesthetics (6.3%) and physician trainees (7.9%). Postgraduate diplomas or certificates were most common among paediatric (41.2%) and obstetrics and gynaecology (25.6%) registrars. CONCLUSION: This is the first study to investigate the additional qualifications of specialists in training in Australia. Almost half of specialists in training surveyed (46.7%) have completed some form of additional study, whether it is a PhD, Master's, postgraduate diploma/certificate or research degree from medical school. Trainees of specialist training schemes are more qualified than specialists who trained in the past Aust Fam Physician 32:92-4, 2003.

Recurrent sampling and ventriculostomy-associated infections: a case-control study.

BACKGROUND: External ventricular drain (EVD) insertion is a common neurosurgical procedure with a significant risk of ventriculostomy-associated infections (VAIs), other morbidities and mortality. Several risk factors have been identified but their effect is unclear. OBJECTIVE: Our primary objective was to assess whether recurrent EVD sampling increased the risk of VAIs. The secondary objective was to explore the effect of sampling frequency, duration of EVD stay, presence of cerebrospinal fluid leak and concurrent infections. METHODS: Ours was a retrospective, single-centre, age-matched, case control study of 83 patients and 249 controls who underwent EVD insertion between 1 January 2010 - 31 December 2016. Patients with primary CNS infections, age under 1 year and death within 5 days of EVD insertion were excluded. Blinded abstractors collected all patient data through the electronic patient record system and regression analysis was used to compare the two groups. RESULTS: Sampling the EVD more than once did not increase the risk of infection (OR 0.47, 95% CI 0.27-0.83, p = 0.01). Risk factors significantly associated with VAI included CSF leak (OR 2.06, 95% CI 1.16-3.67, p = 0.01), concurrent infection (OR 1.85, 95% CI 1.09-3.16, p = 0.02), and an EVD duration of >10 days (OR 2.28, 95% CI 1.24-4.18, p = 0.01). CONCLUSION: Our findings do not support the notion that increased sampling of EVDs is associated with a higher risk of VAI. CSF leaks, concurrent infection and long-term EVDs are also statistically significant risk factors for infection.

Ultralow-Noise Atomic-Scale Structures for Quantum Circuitry in Silicon.

The atomically precise doping of silicon with phosphorus (Si:P) using scanning tunneling microscopy (STM) promises ultimate miniaturization of field effect transistors. The one-dimensional (1D) Si:P nanowires are of particular interest, retaining exceptional conductivity down to the atomic scale, and are predicted as interconnects for a scalable silicon-based quantum computer. Here, we show that ultrathin Si:P nanowires form one of the most-stable electrical conductors, with the phenomenological Hooge parameter of low-frequency noise being as low as ≈10(-8) at 4.2 K, nearly 3 orders of magnitude lower than even carbon-nanotube-based 1D conductors. A in-built isolation from the surface charge fluctuations due to encapsulation of the wires within the epitaxial Si matrix is the dominant cause for the observed suppression of noise. Apart from quantum information technology, our results confirm the promising prospects for precision-doped Si:P structures in atomic-scale circuitry for the 11 nm technology node and beyond.

Sustained release of neurotrophin-3 via calcium phosphate-coated sutures promotes axonal regeneration after spinal cord injury.

Because of the dynamics of spinal cord injury (SCI), the optimal treatment will almost certainly be a combination approach to control the environment and promote axonal growth. This study uses peripheral nerve grafts (PNGs) as scaffolds for axonal growth while delivering neurotrophin-3 (NT-3) via calcium phosphate (CaP) coatings on surgical sutures. CaP coating was grown on sutures, and NT-3 binding and release were characterized in vitro. Then, the NT-3-loaded sutures were tested in a complete SCI model. Rats were analyzed for functional improvement and axonal growth into the grafts. The CaP-coated sutures exhibited a burst release of NT-3, followed by a sustained release for at least 20 days. Functionally, the rats with PNGs + NT-3-loaded sutures and the rats treated with PNGs scored significantly higher than controls on day 56 postoperatively. However, functional scores in rats treated with PNGs + NT-3-loaded suture were not significantly different from those of rats treated with PNGs alone. Cholera toxin subunit B (CTB) labeling rostral to the graft was not observed in any controls, but CTB labeling rostral to the graft was observed in almost all rats that had had a PNG. Neurofilament labeling on transverse sections of the graft revealed that the rats treated with the NT-3-loaded sutures had significantly more axons per graft than rats treated with an NT-3 injection and rats without NT-3. These data demonstrate that PNGs serve as scaffolds for axonal growth after SCI and that CaP-coated sutures can efficiently release NT-3 to increase axonal regeneration. © 2016 Wiley Periodicals, Inc.

Detecting grizzly bear use of ungulate carcasses using global positioning system telemetry and activity data.

Global positioning system (GPS) wildlife collars have revolutionized wildlife research. Studies of predation by free-ranging carnivores have particularly benefited from the application of location clustering algorithms to determine when and where predation events occur. These studies have changed our understanding of large carnivore behavior, but the gains have concentrated on obligate carnivores. Facultative carnivores, such as grizzly/brown bears (Ursus arctos), exhibit a variety of behaviors that can lead to the formation of GPS clusters. We combined clustering techniques with field site investigations of grizzly bear GPS locations (n = 732 site investigations; 2004-2011) to produce 174 GPS clusters where documented behavior was partitioned into five classes (large-biomass carcass, small-biomass carcass, old carcass, non-carcass activity, and resting). We used multinomial logistic regression to predict the probability of clusters belonging to each class. Two cross-validation methods-leaving out individual clusters, or leaving out individual bears-showed that correct prediction of bear visitation to large-biomass carcasses was 78-88 %, whereas the false-positive rate was 18-24 %. As a case study, we applied our predictive model to a GPS data set of 266 bear-years in the Greater Yellowstone Ecosystem (2002-2011) and examined trends in carcass visitation during fall hyperphagia (September-October). We identified 1997 spatial GPS clusters, of which 347 were predicted to be large-biomass carcasses. We used the clustered data to develop a carcass visitation index, which varied annually, but more than doubled during the study period. Our study demonstrates the effectiveness and utility of identifying GPS clusters associated with carcass visitation by a facultative carnivore.

Coding sequence density estimation via topological pressure.

We give a new approach to coding sequence (CDS) density estimation in genomic analysis based on the topological pressure, which we develop from a well known concept in ergodic theory. Topological pressure measures the 'weighted information content' of a finite word, and incorporates 64 parameters which can be interpreted as a choice of weight for each nucleotide triplet. We train the parameters so that the topological pressure fits the observed coding sequence density on the human genome, and use this to give ab initio predictions of CDS density over windows of size around 66,000 bp on the genomes of Mus Musculus, Rhesus Macaque and Drososphilia Melanogaster. While the differences between these genomes are too great to expect that training on the human genome could predict, for example, the exact locations of genes, we demonstrate that our method gives reasonable estimates for the 'coarse scale' problem of predicting CDS density. Inspired again by ergodic theory, the weightings of the nucleotide triplets obtained from our training procedure are used to define a probability distribution on finite sequences, which can be used to distinguish between intron and exon sequences from the human genome of lengths between 750 and 5,000 bp. At the end of the paper, we explain the theoretical underpinning for our approach, which is the theory of Thermodynamic Formalism from the dynamical systems literature. Mathematica and MATLAB implementations of our method are available at http://sourceforge.net/projects/topologicalpres/ .

Routine but risky: a multi-centre analysis of the outcomes of cranioplasty in the Northeast of England.

BACKGROUND: Cranioplasty is undertaken as a routine secondary operation following craniectomy. At a time when decompressive craniectomy is being evaluated by several large trials, we aimed to evaluate the morbidity associated with cranioplasty and investigate its potential effect on outcome. METHODS: The outcomes of 166 patients undergoing cranioplasty at two centres in the United Kingdom between June 2006 and September 2011 were retrospectively analysed. Outcome measures included mortality, morbidity and functional outcome determined by the modified Rankin score (mRS) at last follow-up. A logistic regression analysis was performed to model and predict determinants related to neurological outcome following cranioplasty. RESULTS: Sixty-seven out of 166 patients (40.4 %) experienced at least one complication during a median follow-up time of 15 months (inter-quartile range 5-38 months). Thirty six patients (21.7 %) developed infection requiring antibiotics, with 27 (16.3 %) requiring removal of the cranioplasty. Nine of 25 patients (36 %) with bi-frontal defects developed an infection whereas 21 of the 153 patients (16.4 %) with a defect other than bi-frontal developed an infection (Chi square p = 0.009). Further surgery in the two groups was required in 16.4 % and 11.7, % respectively. Pseudomeningocoele (9 %), seizures (8.4 %) and poor cosmesis (7.2 %) were also commonly observed. Logistic regression analysis identified initial operation (p < 0.03), mRS at the time of cranioplasty (p < 0.0001) and complications (p < 0.04) as being predictive of neurological outcome at last follow-up. Age at the time of cranioplasty and the timing of cranioplasty were not predictive of last mRS score at follow-up. CONCLUSIONS: Cranioplasty harbours significant morbidity, a risk that appears to be higher with a bifrontal defect. The complications experienced influence subsequent functional outcome. The timing of cranioplasty, early or late, after the initial operation does not impact on the ultimate outcome. These findings should be considered when making decisions relating to craniectomy and cranioplasty.

High-coherence electron and ion bunches from laser-cooled atoms.

Cold atom electron and ion sources produce electron bunches and ion beams by photoionization of laser-cooled atoms. They offer high coherence and the potential for high brightness, with applications including ultra-fast electron-diffractive imaging of dynamic processes at the nanoscale. The effective brightness of electron sources has been limited by nonlinear divergence caused by repulsive interactions between the electrons, known as the Coulomb explosion. It has been shown that electron bunches with ellipsoidal shape and uniform density distribution have linear internal Coulomb fields, such that the Coulomb explosion can be reversed using conventional optics. Our source can create bunches shaped in three dimensions and hence in principle achieve the transverse spatial coherence and brightness needed for picosecond-diffractive imaging with nanometer resolution. Here we present results showing how the shaping capability can be used to measure the spatial coherence properties of the cold electron source. We also investigate space-charge effects with ions and generate electron bunches with durations of a few hundred picoseconds. Future development of the cold atom electron and ion source will increase the bunch charge and charge density, demonstrate reversal of Coulomb explosion, and ultimately, ultra-fast coherent electron-diffractive imaging.

Robust Responses of Female Caribou to Changes in Food Supply.

AbstractUngulates can respond to changes in food supply by altering foraging behavior, digestive function, and metabolism. A multifaceted response to an environmental change is considered robust. Short seasons of plant growth make herbivores sensitive to changes in food supply because maintenance and production must be accomplished in less time with fewer options in a more fragile response. Caribou live at high latitudes where short summers constrain their response to changes in food supply. We measured the ability of female caribou to resist and tolerate changes in the quality and quantity of their food supply during winter and summer. Caribou resisted changes in food abundance and quality by changing food intake and physical activity with changes in daily temperature within each season. Peak food intake rose by 134% from winter pregnancy to summer lactation (98 vs. 229 g kg-0.75 d-1), as digestible requirements to maintain the body increased by 85% for energy (1,164 vs. 2,155 kJ kg-0.75 d-1) and by 266% for N (0.79 vs. 2.89 g N kg-0.75 d-1). Caribou required a diet with a digestible content of 12 kJ g-1 and 0.8% N in pregnancy, 18 kJ g-1 and 1.9% N in early lactation, and 11 kJ g-1 and 1.2% N in late lactation, which corresponds with the phenology of the wild diet. Female caribou tolerated restriction of ad lib. food intake to 58% of their energy requirement (680 vs. 1,164 kJ kg-0.75 d-1) during winter pregnancy and to 84% of their energy requirement (1,814 vs. 2,155 kJ kg-0.75 d-1) during summer lactation without a change in stress level, as indicated by fecal corticosterone concentration. Conversely, caribou can respond to increased availability of food with a spare capacity to process digestible energy and N at 123% (2,642 vs. 2,155 kJ kg-0.75 d-1) and 145% (4.20 vs. 2.89 g N kg-0.75 d-1) of those respective requirements during lactation. Robust responses to changes in food supply allow caribou to sustain reproduction, which would buffer demographic response. However, herds may decline when thresholds of behavioral resistance and physiological tolerance are frequently exceeded. Therefore, the challenge for managing declining populations of caribou and other robust species is to identify declines in robustness before their response becomes fragile.