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Purpose: Patients with COVID-19 undergoing hip fracture surgeries have a 30-day mortality of up to 34%. We aimed to evaluate the association between anesthesia technique and 30-day mortality after hip fracture surgery in patients with COVID-19. Methods: After ethics approval, we performed a retrospective cohort analysis of the American College of Surgeons National Surgical Quality Improvement Program data set from January to December 2021. Inclusion criteria were age ≥ 19 yr, laboratory-confirmed SARS-CoV-2 infection within 14 days preoperatively, and hip fracture surgery under general anesthesia (GA) or spinal anesthesia (SA). Exclusion criteria were American Society of Anesthesiologists Physical Status V, ventilator dependence, international normalized ratio ≥ 1.5, partial thromboplastin time > 35 sec, and platelet count < 80 × 109L−1. The primary outcome was all-cause 30-day mortality. The adjusted association between anesthetic technique and 30-day mortality was analyzed using multivariable logistic regression. Results: Of 23,045 patients undergoing hip fracture surgery, 331 patients met the study criteria. The median [interquartile range] age was 82 [74–88] yr, and 32.3% were male. The 30-day mortality rate was 10.0% (33/331) for the cohort (10.7%, 29/272 for GA vs6.8%, 4/59 for SA; P= 0.51; standardized mean difference, 0.138). The use of SA, compared with GA, was not associated with decreased mortality (adjusted odds ratio, 0.61; 95% confidence interval, 0.21 to 1.8; E-value, 2.49). Conclusion: Anesthesia technique was not associated with mortality in patients with COVID-19 undergoing hip fracture surgery. The findings were limited by a small sample size. Study registration: www.ClinicalTrials.gov (NCT05133648); registered 24 November 2021.

Sinuous channels wandering through coastal wetlands have been thought to lack lateral‐migration features like meander cutoffs and oxbows, spurring the broad interpretation that tidal and fluvial meanders differ morphodynamically. Motivated by recent work showing similarities in planform dynamics between tidal and fluvial meandering channels, we analyzed meander neck cutoffs from diverse tidal and fluvial environments worldwide, and show that tidal cutoffs are widespread. Their perceived paucity stems from pronounced channel density and hydrological connectivity in coastal wetlands, comparatively small size of most tidal channels, and typically dense vegetation cover. Although these factors do not efface tidal meander cutoffs, they collectively inhibit oxbow formation and make tidal cutoffs ephemeral features that can escape detection. We argue that similar morphodynamic processes drive cutoff formation in tidal and fluvial landscapes, with differences arising only during post‐cutoff evolution. Such process similarity has important implications for understanding coastal wetland ecomorphodynamics and predicting their long‐term evolution. The sinuous channels that wander through tidal coastal wetlands look like meandering rivers. However, features of alluvial floodplains that indicate active river meandering over time, such as oxbow lakes and meander cutoffs, are difficult to find in tidal settings. Their apparent absence has led researchers to infer that tidal and fluvial meanders evolve differently. We re‐examined this inference by identifying, measuring, and compiling examples of meander cutoffs from a variety of tidal coastal wetlands and fluvial floodplains worldwide. Our analysis suggests that the shapes and geometric properties of tidal and fluvial cutoffs are indeed remarkably similar. This indicates that while tidal and fluvial environments differ in many ways, they nevertheless share the same physical mechanism affecting meander morphodynamical evolution. Differences between tidal and fluvial meanders do arise after a meander is cut off. We observe that tidal meanders remain preferentially connected to the parent channel, preventing the formation of crescent‐shaped oxbow lakes and thus making tidal cutoffs more difficult to detect. Our results indicate a close similarity in meandering channel behavior across tidal and fluvial systems, which opens new opportunities for how researchers model tidal wetlands, with important implications for the effective conservation and restoration of these critical ecosystems. Tidal meander cutoffs are far more common than typically thought and share remarkable morphometric similarities with fluvial counterpartsSimilar mechanisms trigger cutoffs in both tidal and fluvial landscapes, with differences arising only during post‐cutoff evolutionTidal cutoffs seldom disconnect from parent channels and rarely form oxbows due to the high hydrological connectivity of tidal wetlands Tidal meander cutoffs are far more common than typically thought and share remarkable morphometric similarities with fluvial counterparts Similar mechanisms trigger cutoffs in both tidal and fluvial landscapes, with differences arising only during post‐cutoff evolution Tidal cutoffs seldom disconnect from parent channels and rarely form oxbows due to the high hydrological connectivity of tidal wetlands

•A 1st cent BC burial has grave goods with oppositional gender associations.•The highly degraded skeletal remains have hitherto precluded sex determination.•We now determine sex as female using dental enamel peptides.•She may have had a leading role organising / participating in raiding-type warfare.•Alternatively, it is possible that grave goods may not symbolise social roles.

Landscape evolution models (LEMs) are dependent on their initial conditions (ICs). Commonly, LEMs use a horizontal surface with randomized perturbations as their IC and tend toward a steady state under constant forcing. The initial and steady state topographies are inherently linked, but they bear no obvious resemblance to each other. Here we reveal a connection by adding a shallow sinusoidal channel to the IC. This channel transforms into a deep canyon at steady state. Hence, the general behavior of LEMs is to indefinitely preserve topographic features from their ICs. Then we test whether experimental landscapes exhibit a similar behavior. In our experiments, we use the same sinusoidal signal, but find that it is ultimately erased. We believe that the culprit reorganizing processes are lateral channel migration and spatiotemporal variability in incision. Our results imply that LEMs are missing fundamental mechanisms and that long‐term preservation of ICs in erosional environments is unlikely. Researchers use computer simulations and sandbox experiments to model how mountains develop over geologic time. The computer models are aptly named landscape evolution models. These models predict that rivers and mountains remain static on the landscape over long periods of time, but the experiments imply that they fluctuate endlessly. In this paper, we compare the landscape evolution models to landscape experiments and hypothesize that the reason they differ in their behavior is because the models are missing key processes that describe how rivers erode. Numerical landscape evolution models preserve topographic signals from initial conditions indefinitelyExperimental landscapes frequently reorganize their drainage networks and destroy past topographic signalsIn the experiments, we suggest that lateral channel migration and autogenic knickpoints are the drivers of drainage network reorganization

River deltas are built by cycles of lobe growth and abrupt channel shifts, or avulsions, that occur within the backwater zone of coastal rivers. Previous numerical models differ on the origin of backwater‐scaled avulsion nodes and their consistency with experimental data. To unify previous work, we developed a numerical model of delta growth that includes backwater hydrodynamics, river mouth progradation, relative sea level rise, variable flow regimes, and cycles of lobe growth, abandonment, and reoccupation. For parameter space applicable to lowland deltas, we found that flow variability is the primary mechanism to cause persistent avulsion nodes by focusing aggradation within the backwater zone. Backwater‐scaled avulsion nodes also occur under less likely scenarios of initially uniform bed slopes or during rapid relative sea level rise and marine transgression. Our findings suggest that flow variability is a fundamental control on long‐term delta morphodynamics. River deltas are important for farming and drinking water, human populations, and diverse wildlife. Rivers on deltas are unstable and abruptly change course every 10–1,000 years. These channel shifts are necessary for sustaining coastal landscapes and also pose significant hazards. Here we present a mathematical model that shows how rivers require occasional floods, similar to what is observed on natural rivers, to give rise to a predictable location where rivers shift their course. Model simulations without floods produce rivers that change course at random locations, unlike natural rivers. Our findings resolve differences in previous studies about the importance of floods and illustrate that occasional floods are necessary for natural delta growth. Rivers on lowland deltas have repeated avulsions at a preferential location at the delta apex that scales with the backwater lengthA preferential avulsion node occurs due to flow variability that focuses bed aggradation in the backwater zoneA preferential node under constant discharge simulations in previous work resulted from assumed initial conditions of uniform bed slope

Turbidity currents run out over 100 km in lakes and reservoirs, and over 1,000 km in the ocean. They do so without dissipating themselves via excess entrainment of ambient water. Existing layer‐averaged formulations cannot capture this. We use a numerical model to describe the temporal evolution of a turbidity current toward steady state under condition of zero net sediment flux at the bed. The flow self‐partitions itself into two layers. The lower “driving layer” approaches an invariant flow thickness, velocity profile, and suspended sediment concentration profile that sequesters nearly all of the suspended sediment. This layer can continue indefinitely at steady state over a constant bed slope. The upper “driven layer” contains a small fraction of the suspended sediment. The devolution of the flow into these two layers likely allows the driving layer to run out long distances. The downward sediment settling flux of turbidity currents fights back against unconstrained vertical sediment mixingTurbidity currents have a steady state solution where nearly all the sediment is contained in a lower layer that drives the currentThe devolution of the flow into two layers allows the driving layer to run out long distances without dilution of suspended sediment

Copyright of Atenea (07180462) is the property of Universidad de Concepcion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sodium pentobarbital, a euthanasia drug, can persist in animal carcasses following euthanasia and can cause secondary toxicosis to animals that consume the remains. This experiment was conducted to observe the effects of composting on euthanized horse carcass degradation and sodium pentobarbital residues in compost material up to 367 d. Six separate compost bins were constructed on pastureland. Three bins served as the control while 3 served as the treatment. The carbonaceous material, or bulking agent, consisted of hardwood chips mixed with yard waste wetted to approximately 50% moisture content. Bulking agent was added to each bin at a depth of 0.46 m, creating the pad. A licensed veterinarian provided 6 horse carcasses for use in the experiment. These horses had required euthanasia for health reasons. All horses were weighed and then sedated with an intravenous injection of 8 mL of xylazine. After sedation the 3 horses in the treatment group were euthanized by intravenous injection of 60 mL of sodium pentobarbital. The 3 control group horses were anesthetized by intravenous injection of 15 mL of ketamine hydrochloride and then humanely euthanized by precise gunshot to the temporal lobe. Following euthanasia, each carcass was placed on the center of the pad and surrounded with 0.6 m of additional bulking agent. Serum and liver samples were obtained immediately following death. Compost samples were obtained on d 7, 14, 28, 56, 84, 129, 233, and 367 while soil samples were obtained on d -1 and 367. Each sample was analyzed for sodium pentobarbital concentration. Compost pile and ambient temperatures were also recorded. Composting successfully degraded soft tissue with only large bones remaining. Data illustrate that sodium pentobarbital was detectable up to 367 d in compost piles with no clear trend of concentration reduction. Drug residues were detected in soil samples indicating that sodium pentobarbital leached from the carcass and through the pad. These findings confirm the persistence of sodium pentobarbital from equine mortality compost piles and emphasize the importance of proper carcass management of animals euthanized with a barbiturate to reduce environmental impact and secondary toxicosis.

This paper investigates the effect of using an extrinsic implant on the behaviour of SiGe HBTs at low temperatures. The collector current characteristics of SiGe HBTs with different geometries are measured at temperatures from 77 to 300K. The temperature dependence of the collector current is different for devices with different geometries and this results from base profile broadening in the vicinity of the extrinsic base implant due to point defects. Process and device simulators are used to explain this effect. A method for eliminating this geometry dependence of the collector current is also described.

Photonic band gaps (PBGs) are highly sensitive to lattice geometry and dielectric contrast. Here, we report theoretical and experimental confirmation of PBGs in photonic crystals (PhCs) with increasing levels of structural isotropy. These structures are: a standard 6-fold hexagonal lattice, a locally 12-fold Archimedean-like crystal, a true quasicrystal generated by non-random Stampfli inflation, and a biomimetic crystal based on Fibonacci phyllotaxis. Experimental transmission spectra were obtained at microwave frequencies using high-index alumina ( = 9.61) rods. The results were compared to FDTD-calculated transmission spectra and PWE-calculated band diagrams. Wide and deep (> 60dB) primary TM gaps present in all high-index samples are related to reciprocal space vectors with the strongest Fourier coefficients. Their mid-gap frequencies are largely independent of the lattice geometry for comparable fill factors, whereas the gap ratios shrink monotonically as structural isotropy increases.

Gallium lanthanum oxysulfide (GLSO) is a promising host material for observing strong upconversion emission from trivalent rare-earth ions such as erbium (Er3+). Its attractive properties include high rare-earth solubility due to the lanthanum content of the glass former, a high refractive index (n= 2.2 at 550nm) for high radiative efficiency, and a low maximum phonon energy of approximately 425cm -1. Photonic crystals meanwhile can provide controlled light extraction, and may be capable of suppressing unwanted IR emission from lower lying metastable states. Here, we describe the fabrication of photonic crystals in annealed films of Er3+-doped GLSO deposited by RF sputtering. The most intense visible upconversion emission is observed in films annealed at 550°C, close to the bulk glass transition temperature. Hexagonal lattice photonic crystals are subsequently milled into the films using a focused ion beam (FIB). The milling parameters are optimized to produce the most vertical sidewall profile.

Thin films of two different dielectric materials (Yttrium Oxide and Tantalum Pentoxide) were deposited by reactive sputtering and reactive evaporation to determine their suitability as a host for a rare earth doped planar waveguide upconversion laser. The optical properties, structure and crystalline phase of the films were found to be dependent on the deposition method and process parameters. X-ray diffraction (XRD) analysis on several of the 'as-deposited' thin films revealed that the films vary from amorphous to highly crystalline depending on material and process parameters. SEM imaging of the Yttrium Oxide layers revealed a regular column structure confirming their crystalline nature and SEM imaging of the Tantalum Pentoxide layers revealed a smooth amorphous layer confirming their XRD diffractrograms. The dielectric thin film layers which allowed guiding in both the visible and infra-red regions of the spectrum had a more amorphous structure.

Thin films of erbium doped tantalum pentoxide were prepared on unheated <100> orientated silicon substrates with a thermally grown 2 m thick SiO2 layer using reactive sputtering in an oxygen rich environment for upconversion laser experiments. Tantalum and Erbium metal targets were co-sputtered using an ion beam assisted reactive process to produce the high quality amorphous thin film layers. The Erbium dopant concentration was adjusted by varying the relative deposition rate. Slab waveguide loss before high temperature annealing was measured to be 0.8 dB/cm at 633 nm which reduced to 0.5 dB/cm after annealing at 500 °C. Micron scale waveguides were etched into the deposited thin film slab waveguides using photolithography and reactive ion etching. Finally a silicon dioxide buffer layer was deposited on top of the ridge waveguides to help constrict the laser mode and to add a protective layer. 2 cm long waveguide samples were cleaved and polished to achieve good optical quality end facets for laser experiments. Upconversion efficiency and laser gain measurements were performed on the final waveguides. Waveguide losses of 6.35 dB/cm were measured for the final ridge waveguides and a coupling efficiency of 48 % was obtained. A positive net gain of 0.25 dB was measured for upconversion to 551 nm using a pump probe optical setup.

Wildlife rehabilitation seeks to return healthy animals back to their natural habitat with good survival prospects,and hence contribute to the persistence of their populations. However, the effectiveness of rehabilitation remains largelyundocumented, and its utility as a conservation tool is unclear. In this paper, we document the rehabilitation successof a large, herbivorous marsupial, the common wombat (Vombatus ursinus), and use the findings as a case study toevaluate the contribution that rehabilitation can make to wildlife conservation. Using a database of 54 orphaned wombatsmonitored for up to eight years, we found that 81.5% of young survived to release and, of those, 77.3% were alivein the wild by the end of the study. Survival during rehabilitation was greater for larger, older animals, but influencedalso by problems during care, reaction to human contact following weaning and, in particular, the responses ofindividuals to treatment. No factors associated with rescue condition, rehabilitation or release affected survival of animalsonce returned to the wild, suggesting that wombats were not disadvantaged by their progression through rehabilitation.We provide brief recommendations to improve rehabilitation success for wombats. We conclude that rehabilitation isan under-recognized but potentially valuable conservation tool, and suggest that it is timely to consider its contributionto wildlife management more generally.

Abstract: This paper presents preliminary control system simulation results in a urea-selective catalytic reduction (SCR) aftertreatment system based on NH3 sensor feedback. A four-state control-oriented lumped parameter model is used to analyze the controllability and observability properties of the urea-SCR plant. A model-based estimator is designed via simulation and a control system is developed with design based on a sliding mode control framework. The control system based on NH3 sensor feedback is analyzed via simulation by comparing it to a control system developed based on NOx sensor feedback. Simulation results show that the NH3 sensor-based strategy performs very similarly in comparison to a NOx sensor-based strategy. The control system performance metrics for NOx index, urea index, urea usage, and NH3 slip suggest that the NOx sensor can be a potential alternative to a NOx sensor for urea-SCR control applications.

AbstractExhaust from conventional internal combustion engines (ICEs) burning diesel or biofuels is discussed in relation to emissions at the wharf and the associated human health effects. This paper will for the first time discuss the absolute advantage of commercial hybrid electric vessels over conventional ICE burning diesel or biofuels. That is, commercial hybrid vessels, either in “series” or “parallel” configurations, that included the option of use of renewable energy enable zero particulate and toxic gas emissions at the wharf.

Parallel-plate electrostatic actuators are a simple way to achieve piston motion for large numbers of mirrors in spatial light modulators. However, selection of design parameters is made difficult by their nonlinear behavior. This paper presents simple models for predicting static and dynamic behaviors of fixed-fixed parallel-plate electrostatic actuators. Static deflection equations are derived based on minimization of the total potential energy of the beam. Beam bending, residual stress, beam stretch and applied electrostatic force are included in the potential energy formulation. Computation time is reduced by working with assumed mode shapes. The problem of predicting midpoint beam deflection has been reduced to finding the roots of a third-order equation. Model results are compared to finite-element analysis results. In the dynamic analysis, Lagrange's method is used to derive the nonlinear equation of motion. An equation for predicting natural frequency, assuming small midpoint deflections about a dc setpoint, is presented. In addition, the effect of gas pressure on the damped natural frequency of a rigid actuator is analyzed. Experimental measurements of static deflection and frequency response are compared to model predictions. The actual micromirrors exhibit less strain stiffening than the model predicts.

In this paper the model presented in the companion paper, Wright and Parker (2005) is applied to a generic river reach typical of a large, sand-bed river flowing into the ocean in order to investigate the mechanisms controlling longitudinal profile development and downstream fining. Three mechanisms which drive downstream fining are studied: a delta prograding into standing water, sea-level rise, and tectonic subsidence. Various rates of sea-level rise (typical of the late Holocene) and tectonic subsidence are modeled in order to quantify their effects on the degree of profile concavity and downstream fining. Also, several other physical mechanisms which may affect fining are studied, including the relative importance of the suspended versus bed load, the effect of the loss of sediment overbank, and the influence of the delta bottom slope. Finally, sensitivity analysis is used to show that the grain-size distribution at the interface between the active layer and substrate has a significant effect on downstream fining.

In this paper a numerical modeling formulation is presented for simulation of the development of the longitudinal profile and bed sediment distribution in sand-bed rivers. The objective of the model application, which is presented in the companion paper (Wright and Parker, 2005), is to study the development of two characteristics of large, low-slope, sand-bed rivers: (1) a downstream decrease in bed slope (i.e. concave upward longitudinal profile) and (2) a downstream decrease in characteristic bed sediment diameter (e.g. the median bed surface size D50). Three mechanisms that lead to an upward concave profile and downstream fining are included in the modeling formulation: (1) a delta prograding into standing water at the downstream boundary, (2) sea-level rise, and (3) tectonic subsidence. In the companion paper (Wright and Parker, 2005) the model is applied to simulate the development of the longitudinal profile and downstream fining in sand-bed rivers flowing into the ocean during the past 5000 years of relatively slow sea-level rise.

A superior homonymous quadrantanopia is a well recognized complication of anterior temporal lobe resection and occurs because of disruption of the Meyer loop, the anterior part of the optic radiation. The authors used diffusion tensor imaging tractography to visualize the optic radiation before and after surgery, demonstrating the disruption of Meyer loop in a patient who developed a quadrantanopia. Preoperative imaging of the optic radiation will be useful in predicting visual field defects following temporal lobe resection.

Correlational analyses have shown a moderate strength association between the occurrence of continuous pulsations, a type of geomagnetic activity within the 0.2-Hz to 5-Hz range, and the occurrence of Sudden Infant Deaths. In the present study, rats were exposed continuously from two days before birth to seven days after birth to 0.5-Hz pulsed-square wave magnetic fields whose intensities were within either the nanoTesla or microTesla range. The magnetic fields were generated in either an east-west (E-W) or north-south (N-S) direction. At 21 days of age, the area of the parasolitary nucleus (but not the solitary nucleus) was significantly smaller, and the numbers of neurons were significantly less in rats that had been exposed to the nanoT fields generated in the east-west direction or to the microTesla fields generated within either E-W or N-S direction relative to those exposed to the N-S nanoTesla fields. These results suggest nanoTesla magnetic fields, when applied in a specific direction, might interact with the local geomagnetic field to affect cell migration in structures within the brain stem that modulate vestibular-related arousal and respiratory or cardiovascular stability.

No abstract.

Reaction of homoallylic alcohols with aldehydes in the presence of TFA gives, after hydrolysis of the ester, 4-hydroxy-2,3,6-trisubstituted tetrahydropyrans with the creation of three new stereocenters in a single-pot process. By varying the aldehyde component, a variety of functionalized side chains are installed at C-2. The utility of this approach is extended to the enantioselective synthesis of tetrahydropyrans with >99% ee.

A popular theory has proposed that anisogamy originated through disruptive selection acting on an ancestral isogamous population, though recent work has emphasized the importance of other factors in its evolution. We re–examine the disruptive selection theory, starting from an isogamous population with two mating types and taking into account the functional relationship, g(m), between the fitness of a gamete and its size, m, as well as the relationship, f(S), between the fitness of a zygote and its size, S. Evolutionary game theory is used to determine the existence and continuous stability of isogamous and anisogamous strategies for the two mating types under various models for the two functions g(m) and f(S). In the ancestral unicellular state, these two functions are likely to have been similar; this leads to isogamy whether they are sigmoidal or concave, though in the latter case allowance must be made for a minimal gamete size. The development of multicellularity may leave g(m) relatively unchanged while f(S) moves to the right, leading to the evolution of anisogamy. Thus, the disruptive selection theory provides a powerful explanation of the origin of anisogamy, though other selective forces may have been involved in the subsequent specialization of micro– and macrogametes.

The first syntheses of two natural products, catechols 1 and 2, isolated from Plectranthus sylvestris (labiatae), are reported. Oxygen-18 labeling studies support the proposed intermediacy of a stabilized benzylic cation in the acid-promoted cyclization of an aldehyde and benzylic homoallylic alcohol possessing an electron-rich aromatic ring. In contrast, with an electron-deficient aromatic ring the pathway via a benzylic cation is only minor.

This study reports a retrospective analysis of the evidence of cranial venous outflow pathology in 188 patients with pseudotumour syndrome (PTS) investigated over the period 1968–1999. Standard methods of investigation appropriate to the period were used, i.e. cerebral angiography, CT and MR scanning. Recently, some patients had specific venous studies including intraluminal cranial venous sinus pressure measurements. A sub-group (25 patients) was investigated for haematological abnormalities. The overall incidence of cranial venous outflow abnormality was 19.7% (37 cases). In decades, related to the predominant investigative method, the figures were: to 1979, 4.2% (2 cases); to 1989, 15.0% (8 cases); to 1999, 31.0% (27 cases). A cause of the venous abnormality was identified in 20 cases, most commonly haematological and iatrogenic. In 17 patients (all females) no cause was identified. Fifteen of the 25 patients (60%) tested specifically were found to have a haematological abnormality, although no correlation was shown between this and a demonstrable venous outflow abnormality. The conclusion was drawn that there is a high incidence (close to one-third) of venous outflow abnormalities in PTS with detailed investigation. Issues of mechanism and therapy are discussed.

High-throughput methods are utilized in the discovery and optimization of heterogeneous catalyst formulations that promote single-walled carbon nanotube (SWNT) synthesis. Catalyst compositions, substrates, and reaction conditions are varied to efficiently investigate SWNT growth by chemical vapor deposition (CVD). A robotic microarray printer is employed to print libraries of the liquid-based catalyst precursors onto various substrates. After CVD, the catalyst arrays are qualitatively screened for yield via electron microscopy. More comprehensive characterization of candidate catalysts is further investigated with confocal Raman spectroscopy (CRS). Detailed CRS mapping reveals information concerning the printed catalyst and nanotube homogeneity in the microarrays. This powerful characterization approach allows for the high-throughput screening of nanotube type, diameter distribution, and purity within the microarrays. The methodology described has enabled the efficient exploration of synthesis parameters, which has led to the identification of SWNT catalysts with various activities.

We outline and develop current theory on how inherent genetic conflicts of interest between the various family members can affect the flow of parental investment from parents to offspring, and discuss the problems for empirical testing that this generates. The parental investment pattern realized in nature reflects the simultaneous resolution of all the conflicts between the family players. This depends on the genetic mechanism, the mating system and reproductive constraints, on whether extra demand by progeny affects current or future sibs, and particularly on the behavioural mechanisms underlying demand (begging or solicitation) and supply (provision of parental investment by parents). The direction of deviation from the optimal parental investment for the parent(s) depends on the slope of what we term the ‘effect of supply on demand’, the mechanism that determines how changes in food supply affect begging levels. If increasing food increases begging (positive slope), less parental investment is supplied than the parental optimum and if increasing food decreases begging (negative slope), more parental investment is supplied. The magnitude of deviation depends on both the ‘effect of supply on demand’ and on the ‘effect of demand on supply’ (the mechanism determining how changes in begging affect food supply, which always has a positive slope). We conclude that it will often be impossible to deduce the extent of underlying conflict by establishing the amount of parental investment given relative to the ideal optimum for the parent. Some possible directions for future research are discussed.

Dehulled soybean meal prepared from genetically modified, herbicide (glyphosate)-tolerant Roundup Ready soybeans containing the CP4 EPSPS protein and near-isogenic conventional soybeans were assessed in an experiment with growing-finishing pigs. The soybeans were grown in the yr 2000 under similar agronomic conditions except that the Roundup Ready soybeans were sprayed with Roundup herbicide. Both were processed at the same plant. The composition of the two types of soybeans and the processed soybean meal were similar. Corn-soybean meal diets containing conventional or Roundup Ready soybean meal and fortified with minerals and vitamins were fed to 100 cross-bred pigs from 24 to 111 kg BW. Diets contained approximately 0.95% lysine initially and were reduced to 0.80 and 0.65% lysine when pigs reached 55 and 87 kg BW, respectively. There were 10 pens (five pens of barrows and five pens of gilts) per treatment with five pigs per pen. All pigs were scanned at 107 kg mean BW and all barrows were killed at the end of the test for carcass measurements and tissue collection. Rate and efficiency of weight gain, scanned backfat and longissimus area, and calculated carcass lean percentage were not different (P > 0.05) for pigs fed diets containing conventional or Roundup Ready soybean meal. Gilts gained slower, but they were more efficient and leaner (P < 0.05) than barrows. Responses to the type of soybean meal were similar for the two sexes with no evidence of a diet x sex interaction for any of the traits. In most instances, carcass traits of barrows were similar for the two types of soybean meal. Longissimus muscle samples from barrows fed conventional soybean meal tended (P = 0.06) to have less fat than those fed Roundup Ready soybean meal, but water, protein, and ash were similar. Sensory scores of cooked longissimus muscles were not influenced (P > 0.05) by diet. The results indicate that Roundup Ready soybean meal is essentially equivalent in composition and nutritional value to conventional soybean meal for growing-finishing pigs.

Brain atrophy measured by MRI is a potentially useful tool for monitoring disease progression in multiple sclerosis. The location, extent and mechanisms of brain atrophy in early disease are not well documented. Using quantitative MRI, this study investigated whole brain, grey and white matter atrophy in clinically early relapsing–remitting multiple sclerosis and its relationship to lesion measures. Data came from 27 normal control subjects (14 females and 13 males, mean age 36.1 years) and 26 subjects with clinically definite multiple sclerosis (18 females and eight males, mean age 35.1 years, mean delay from first symptom to scan 1.8 years, median Expanded Disability Status Scale score 1.0). All had three‐dimensional fast spoiled gradient recall (3D FSPGR), T1‐weighted pre‐ and post‐gadolinium‐enhanced and T2‐weighted scans. The 3D FSPGR images were automatically segmented into grey and white matter and cerebrospinal fluid using SPM99. 3D FSPGR hypo‐intense, T2 hyper‐intense, T1 hypo‐intense and T1 post‐gadolinium‐enhancing lesion volumes were determined by semi‐automatic lesion segmentation. The SPM99 output was combined with the 3D FSPGR lesion segmentations to quantify tissue volumes as fractions of total intracranial volumes, producing values for the brain parenchymal fraction (BPF), white matter fraction (WMF) and grey matter fraction (GMF). Comparing multiple sclerosis with control subjects, BPF, GMF and WMF were significantly reduced (P < 0.001 for all tissue fractions). Using Pearson correlations, T2 hyper‐intense and T1 hypo‐intense lesion volumes were inversely related to BPF (T2r = –0.78, P < 0.001; T1r = –0.59, P = 0.002) and GMF (T2r = –0.73, P < 0.001; T1 r = –0.53, P = 0.006), but not WMF (T2r = –0.30, P = 0.134; T1r = –0.26, P = 0.199). T1 post‐gadolinium‐enhancing lesion volumes were not correlated with any fractional volumes. These results indicate that significant brain atrophy, affecting both grey and white matter, occurs early in the clinical course of multiple sclerosis. The lack of correlation between lesion load measures and WMF suggests that pathological changes in white matter may occur by mechanisms which are at least partly independent from overt lesion genesis in early multiple sclerosis.

Brain atrophy measured by MRI is a potentially useful tool for monitoring disease progression in multiple sclerosis. The location, extent and mechanisms of brain atrophy in early disease are not well documented. Using quantitative MRI, this study investigated whole brain, grey and white matter atrophy in clinically early relapsing-remitting multiple sclerosis and its relationship to lesion measures. Data came from 27 normal control subjects (14 females and 13 males, mean age 36.1 years) and 26 subjects with clinically definite multiple sclerosis (18 females and eight males, mean age 35.1 years, mean delay from first symptom to scan 1.8 years, median Expanded Disability Status Scale score 1.0). All had three-dimensional fast spoiled gradient recall (3D FSPGR), T(1)-weighted pre- and post-gadolinium-enhanced and T(2)-weighted scans. The 3D FSPGR images were automatically segmented into grey and white matter and cerebrospinal fluid using SPM99. 3D FSPGR hypo-intense, T(2) hyper-intense, T(1) hypo-intense and T(1) post-gadolinium-enhancing lesion volumes were determined by semi-automatic lesion segmentation. The SPM99 output was combined with the 3D FSPGR lesion segmentations to quantify tissue volumes as fractions of total intracranial volumes, producing values for the brain parenchymal fraction (BPF), white matter fraction (WMF) and grey matter fraction (GMF). Comparing multiple sclerosis with control subjects, BPF, GMF and WMF were significantly reduced (P < 0.001 for all tissue fractions). Using Pearson correlations, T(2) hyper-intense and T(1) hypo-intense lesion volumes were inversely related to BPF (T(2) r = -0.78, P < 0.001; T(1) r = -0.59, P = 0.002) and GMF (T(2) r = -0.73, P < 0.001; T(1) r = -0.53, P = 0.006), but not WMF (T(2) r = -0.30, P = 0.134; T(1) r = -0.26, P = 0.199). T(1) post-gadolinium-enhancing lesion volumes were not correlated with any fractional volumes. These results indicate that significant brain atrophy, affecting both grey and white matter, occurs early in the clinical course of multiple sclerosis. The lack of correlation between lesion load measures and WMF suggests that pathological changes in white matter may occur by mechanisms which are at least partly independent from overt lesion genesis in early multiple sclerosis.

Evidence is presented here for the mechanism of the Prins cyclization of benzylic homoallylic alcohols, which shows that the outcome of the reaction is dependent upon the substituents on the aromatic ring. The presence of an electron-rich aromatic ring favors an oxonia-Cope rearrangement yielding a symmetrical tetrahydropyran as the major product formed via a side-chain exchange process. In contrast, with electron-deficient aromatic rings the expected 2,4,6-trisubstituted tetrahydropyran is formed.

Evidence based guidelines are regarded as an appropriate basis for providing effective health care, but few guidelines incorporate the views of users such as carers.

Novel processes for the fabrication of mesoscopic Josephson junction qubits have been developed, based on superconducting Al/Al2O3/Al tunnel junctions. These are fabricated by electron beam lithography using single-layer and multi-layer resists, and standard processes that are compatible with conventional CMOS processing. The new single-layer resist process is found to have significant advantages over conventional fabrication methods using suspended tri-layer shadow masks.

A 7-year-old cat was presented for seizures. Cerebrospinal fluid cytology and serology were consistent with a diagnosis of toxoplasmosis. The cat was treated with clindamycin but seizures continued and additional neurological signs developed over 6 months. A mass lesion was identified in the left cerebral hemisphere using magnetic resonance imaging (MRI). The lesion enhanced after gadolidium and a tumour was considered likely. Histologically, the lesion proved to be a cryptococcal granuloma and retrospective serology confirmed that the cat had cryptococcosis at its initial presentation. This report provides the first description in the veterinary literature of the MRI appearance of a cerebral cryptococcoma and emphasises the importance of performing cryptococcal antigen determination in cats with signs of intracranial disease.