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Quaternary processes and environmental changes are often difficult to assess in remote subantarctic islands due to high surface erosion rates and overprinting of sedimentary products in locations that can be a challenge to access. We present a set of high-resolution, multichannel seismic lines and complementary multibeam bathymetry collected off the eastern (leeward) side of the subantarctic Auckland Islands, about 465 km south of New Zealand's South Island. These data constrain the erosive and depositional history of the island group, and they reveal an extensive system of sediment-filled valleys that extend offshore to depths that exceed glacial low-stand sea level. Although shallow, marine, U-shaped valleys and moraines are imaged, the rugged offshore geomorphology of the paleovalley floors and the stratigraphy of infill sediments suggests that the valley floors were shaped by submarine fluvial erosion, and subsequently filled by lacustrine, fjord, and fluvial sedimentary processes.
Evidence has been accumulating regarding alterations in components of the endocannabinoid system in patients with psychosis. Of all the putative risk factors associated with psychosis, being at clinical high-risk for psychosis (CHR) has the strongest association with the onset of psychosis, and exposure to childhood trauma has been linked to an increased risk of development of psychotic disorder. We aimed to investigate whether being at-risk for psychosis and exposure to childhood trauma were associated with altered endocannabinoid levels.
We compared 33 CHR participants with 58 healthy controls (HC) and collected information about previous exposure to childhood trauma as well as plasma samples to analyse endocannabinoid levels.
Individuals with both CHR and experience of childhood trauma had higher N-palmitoylethanolamine (p < 0.001) and anandamide (p < 0.001) levels in peripheral blood compared to HC and those with no childhood trauma. There was also a significant correlation between N-palmitoylethanolamine levels and symptoms as well as childhood trauma.
Our results suggest an association between CHR and/or childhood maltreatment and elevated endocannabinoid levels in peripheral blood, with a greater alteration in those with both CHR status and history of childhood maltreatment compared to those with either of those risks alone. Furthermore, endocannabinoid levels increased linearly with the number of risk factors and elevated endocannabinoid levels correlated with the severity of CHR symptoms and extent of childhood maltreatment. Further studies in larger cohorts, employing longitudinal designs are needed to confirm these findings and delineate the precise role of endocannabinoid alterations in the pathophysiology of psychosis.
Much of what is known about the Indigenous city of Cahokia, located in and influential on the North American midcontinent during the eleventh through fourteenth centuries AD, derives from decades of salvage, research, and CRM excavations in the surrounding American Bottom region. We use this robust dataset to explore patterns of building conflagration that suggest these practices of burning were part of pre-Mississippian traditions that were bundled into new Cahokian landscapes during the early consolidation of the city. These bundled practices entangled sources of power that were at once political and religious, thus transforming the practices and meanings associated with terminating building use via fire.
Kochia is one of the most problematic weeds in the United States. Field studies were conducted in five states (Wyoming, Colorado, Kansas, Nebraska, and South Dakota) over 2 yr (2010 and 2011) to evaluate kochia control with selected herbicides registered in five common crop scenarios: winter wheat, fallow, corn, soybean, and sugar beet to provide insight for diversifying kochia management in crop rotations. Kochia control varied by experimental site such that more variation in kochia control and biomass production was explained by experimental site than herbicide choice within a crop. Kochia control with herbicides currently labeled for use in sugar beet averaged 32% across locations. Kochia control was greatest and most consistent from corn herbicide programs (99%), followed by soybean (96%) and fallow (97%) herbicide programs. Kochia control from wheat herbicide programs was 93%. With respect to the availability of effective herbicide options, glyphosate-resistant kochia control was easiest in corn, soybean, and fallow, followed by wheat; and difficult to manage with herbicides in sugar beet.
Starting in 2016, we initiated a pilot tele-antibiotic stewardship program at 2 rural Veterans Affairs medical centers (VAMCs). Antibiotic days of therapy decreased significantly (P < .05) in the acute and long-term care units at both intervention sites, suggesting that tele-stewardship can effectively support antibiotic stewardship practices in rural VAMCs.
Background: Cervical sponylotic myelopathy (CSM) may present with neck and arm pain. This study investiagtes the change in neck/arm pain post-operatively in CSM. Methods: This ambispective study llocated 402 patients through the Canadian Spine Outcomes and Research Network. Outcome measures were the visual analogue scales for neck and arm pain (VAS-NP and VAS-AP) and the neck disability index (NDI). The thresholds for minimum clinically important differences (MCIDs) for VAS-NP and VAS-AP were determined to be 2.6 and 4.1. Results: VAS-NP improved from mean of 5.6±2.9 to 3.8±2.7 at 12 months (P<0.001). VAS-AP improved from 5.8±2.9 to 3.5±3.0 at 12 months (P<0.001). The MCIDs for VAS-NP and VAS-AP were also reached at 12 months. Based on the NDI, patients were grouped into those with mild pain/no pain (33%) versus moderate/severe pain (67%). At 3 months, a significantly high proportion of patients with moderate/severe pain (45.8%) demonstrated an improvement into mild/no pain, whereas 27.2% with mild/no pain demonstrated worsening into moderate/severe pain (P <0.001). At 12 months, 17.4% with mild/no pain experienced worsening of their NDI (P<0.001). Conclusions: This study suggests that neck and arm pain responds to surgical decompression in patients with CSM and reaches the MCIDs for VAS-AP and VAS-NP at 12 months.
Introduction: Acute aortic syndrome (AAS) is a time sensitive aortic catastrophe that is often misdiagnosed. There are currently no Canadian guidelines to aid in diagnosis. Our goal was to adapt the existing American Heart Association (AHA) and European Society of Cardiology (ESC) diagnostic algorithms for AAS into a Canadian evidence based best practices algorithm targeted for emergency medicine physicians. Methods: We chose to adapt existing high-quality clinical practice guidelines (CPG) previously developed by the AHA/ESC using the GRADE ADOLOPMENT approach. We created a National Advisory Committee consisting of 21 members from across Canada including academic, community and remote/rural emergency physicians/nurses, cardiothoracic and cardiovascular surgeons, cardiac anesthesiologists, critical care physicians, cardiologist, radiologists and patient representatives. The Advisory Committee communicated through multiple teleconference meetings, emails and a one-day in person meeting. The panel prioritized questions and outcomes, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. The algorithm was prepared and revised through feedback and discussions and through an iterative process until consensus was achieved. Results: The diagnostic algorithm is comprised of an updated pre test probability assessment tool with further testing recommendations based on risk level. The updated tool incorporates likelihood of an alternative diagnosis and point of care ultrasound. The final best practice diagnostic algorithm defined risk levels as Low (0.5% no further testing), Moderate (0.6-5% further testing required) and High ( >5% computed tomography, magnetic resonance imaging, trans esophageal echocardiography). During the consensus and feedback processes, we addressed a number of issues and concerns. D-dimer can be used to reduce probability of AAS in an intermediate risk group, but should not be used in a low or high-risk group. Ultrasound was incorporated as a bedside clinical examination option in pre test probability assessment for aortic insufficiency, abdominal/thoracic aortic aneurysms. Conclusion: We have created the first Canadian best practice diagnostic algorithm for AAS. We hope this diagnostic algorithm will standardize and improve diagnosis of AAS in all emergency departments across Canada.
Declining mortality following invasive pneumococcal disease (IPD) has been observed concurrent with a reduced incidence due to effective pneumococcal conjugate vaccines. However, with IPD now increasing due to serotype replacement, we undertook a statistical analysis to estimate the trend in all-cause 30-day case fatality rate (CFR) in the North East of England (NEE) following IPD. Clinical, microbiological and demographic data were obtained for all laboratory-confirmed IPD cases (April 2006–March 2016) and the adjusted association between CFR and epidemiological year estimated using logistic regression. Of the 2510 episodes of IPD included in the analysis, 486 died within 30 days of IPD (CFR 19%). Increasing age, male sex, a diagnosis of septicaemia, being in ⩾1 clinical risk groups, alcohol abuse and individual serotypes were independently associated with increased CFR. A significant decline in CFR over time was observed following adjustment for these significant predictors (adjusted odds ratio 0.93, 95% confidence interval 0.89–0.98; P = 0.003). A small but significant decline in 30-day all-cause CFR following IPD has been observed in the NEE. Nonetheless, certain population groups remain at increased risk of dying following IPD. Despite the introduction of effective vaccines, further strategies to reduce the ongoing burden of mortality from IPD are needed.
The majority of paediatric Clostridioides difficile infections (CDI) are community-associated (CA), but few data exist regarding associated risk factors. We conducted a case–control study to evaluate CA-CDI risk factors in young children. Participants were enrolled from eight US sites during October 2014–February 2016. Case-patients were defined as children aged 1–5 years with a positive C. difficile specimen collected as an outpatient or ⩽3 days of hospital admission, who had no healthcare facility admission in the prior 12 weeks and no history of CDI. Each case-patient was matched to one control. Caregivers were interviewed regarding relevant exposures. Multivariable conditional logistic regression was performed. Of 68 pairs, 44.1% were female. More case-patients than controls had a comorbidity (33.3% vs. 12.1%; P = 0.01); recent higher-risk outpatient exposures (34.9% vs. 17.7%; P = 0.03); recent antibiotic use (54.4% vs. 19.4%; P < 0.0001); or recent exposure to a household member with diarrhoea (41.3% vs. 21.5%; P = 0.04). In multivariable analysis, antibiotic exposure in the preceding 12 weeks was significantly associated with CA-CDI (adjusted matched odds ratio, 6.25; 95% CI 2.18–17.96). Improved antibiotic prescribing might reduce CA-CDI in this population. Further evaluation of the potential role of outpatient healthcare and household exposures in C. difficile transmission is needed.
Many patients with advanced serious illness or at the end of life experience delirium, a potentially reversible form of acute brain dysfunction, which may impair ability to participate in medical decision-making and to engage with their loved ones. Screening for delirium provides an opportunity to address modifiable causes. Unfortunately, delirium remains underrecognized. The main objective of this pilot was to validate the brief Confusion Assessment Method (bCAM), a two-minute delirium-screening tool, in a veteran palliative care sample.
This was a pilot prospective, observational study that included hospitalized patients evaluated by the palliative care service at a single Veterans’ Administration Medical Center. The bCAM was compared against the reference standard, the Diagnostic and Statistical Manual of Mental Disorders, fifth edition. Both assessments were blinded and conducted within 30 minutes of each other.
We enrolled 36 patients who were a median of 67 years (interquartile range 63–73). The primary reasons for admission to the hospital were sepsis or severe infection (33%), severe cardiac disease (including heart failure, cardiogenic shock, and myocardial infarction) (17%), or gastrointestinal/liver disease (17%). The bCAM performed well against the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, for detecting delirium, with a sensitivity (95% confidence interval) of 0.80 (0.4, 0.96) and specificity of 0.87 (0.67, 0.96).
Significance of Results
Delirium was present in 27% of patients enrolled and never recognized by the palliative care service in routine clinical care. The bCAM provided good sensitivity and specificity in a pilot of palliative care patients, providing a method for nonpsychiatrically trained personnel to detect delirium.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
Total reflection X-ray Fluorescence (TXRF) has been applied to the detection and quantification of metal contamination on the surface and near-surface regions of silicon wafers in the semiconductor industry The need for improving the sensitivity and detection limit of the TXRF technique is driven by the progress in producing thinner films and finer features in the development of larger Mbit DRAMS.
Total reflection X-ray fluorescence (TXRF) analysis of “low Z” elements, Ti, Fe, Ni, Cu, Zn and “high Z” elements, Zr, W, Au, Pb, are required for micro scale semiconductor device production processes. In the past, the W–Lβ X-rays have been used for the analysis of S to Zn.
This paper describes a new three crystal monochromator coupled with a gold direct-drive rotating anode target. This development has produced significant improvements in the sensitivities and LLD's for all measured elements. The monochromator makes the Au Lα (9.71 keV), Au Lβ (11.44 keV) and Au Lγ (13.33 keV) available for routine use in TXRF analyses. The Au Lα X-ray is best used for the lower Z elements, Na to Cu. The best result for W, Cu and Zn are obtained with the Au Lβ X-ray. This is the result of both increased peak intensity and lower background. For the heavier elements, such as Au and Pb, the Au L X-ray yields intensities 100 times higher than what has been achieved in the past.
Over the past few years there has been substantial progress in the TXRF analysis of heavy element surface contamination on silicon wafers. Further advances and improvements are desired in the analytical performance and hardware. Extension of the analytical range to include the light elements is particularly desirable.
In the case of light element analysis, sodium and aluminum impurities have been monitored in the IC production process. The increase of the sodium impurity in a silicon wafer gives rise to a decrease in the insulation in IC devices and the growth of the SiO2 film is disturbed by the prsence of aluminum impurity on the silicon wafer surface.
Advancements in trace clement analysis require improvements in both the signal-to-noise ratio and accurate background correction. With a sequential spectrometer, one can obtain detection limits of around 0.1 ppm for medium to heavy Z elements. Conditions can be individually optimized for each element, for example, selection of filters, collimators, crystals and background subtraction. The disadvantage is that the analysis time may become “long” if many elements are to be analyzed. This long exposure time can lead to the deterioration of some samples.
Electron optics techniques have been applied to the examination of various evidence materials common to forensic science. Vehicular paint fragments, a common evidence material, possess topographical features suitable for SEM analysis and composition variations in the form of chemically distinct layers and surface contaminant particles which can be characterized using energy dispersive X-ray analysis. The ability to analyze paint samples in terms of both topography and composition presents the potential of an extremely valuable tool for forensic investigators.
Over thirty automotive paint samples from many sources were examined in this study, using either the secondary electron image of the SEM or the SEM image combined with concurrent X-ray analysis by an energy dispersive System. Topographical pictures and X-ray spectra were recorded and comparisons between samples were made. Additional characterization of specimens was attempted through the analysis of individual paint layers.
The data obtained was used to group the paint samples into categories used for identification of the sample source. This information is valuable to several types of criminal investigation.
Several interesting phenomena involving ultra-soft X-rays and synthetic multilayer crystals were studied as a result of the on-going process of improving the Rigaku Mode] 3630 Wafer Analyzer for the measurement of BPSG (1000-2500 Å) and other thin films.1-3 These phenomena can be divided into four categories; “ghost” peaks, diffraction from the substrate, fluorescence from the multilayer and higher order lines from the multilayer. Each of these is a potential snurce nf error in the measurement of ultra-soft X-rays, Fortunately, as will be shown, each can be readily dealt with.
The photons resulting from the interaction of beta particles and matter have a certain complexity of origin; but the spectrum is made up, in large part, of two primary components, one of these being the white radiation continuum produced by the external bremsstrahlung mechanism of beta acceleration at the target atom. The second fraction consists of the characteristic K and L X-rays of the target atom. Published beta-excited X-ray spectra are centered about a small fraction of the available pure beta emitters and a restricted group of target materials. Furthermore, intercomparisons between references are difficult, due to an infinite variety of source and detector parameters influencing the data.
This laboratory has begun a comprehensive reference compilation of these spectra, done on a comparative basis and simplified and standardized for sensible cataloging and easy reproduction of the experimental design. The prime purpose is to make available coherent data for many beta-excited X-ray sources in which beta activities, target geometries, and other critical parameters are known, controlled, and constant. Spectral sets for given source-target combinations may, therefore, be intercompared, and application of the beta-excited X-ray may be made with the best possible source-target atom combination.
The spectra are studied by three proportional counters (operating down to the 1 kV energy range) and two standard scintillation crystals, accumulated in a 256-channel analyzer, and are presented in sets (representing one beta source-target combination) consisting of a minimum of eight spectra, six of which represent the most critical transmission target geometry.
Examples of the cataloging of the spectral sets, for the mixture, apposition, and compound isotopic X-ray sources, are presented.
The wafer analyzer has been used to fulfil many applications needs in the semiconductor industry. The prominent features of the XRF method for the semiconductor industry are:analysis of many types of films, e.g., oxides, silicides and metallic alloys, and simultaneous analysis of film thickness and compositions.
In the past, the analysis results of BPSG (Boron-doped Phospho-Silicate Glass) films, with thicknesses greater than 4000 Å, were reported. With the recent increased demand for larger scale and higher quality semiconductor devices (larger than 64 Mbit), more accurate analysis with high precision has been required.