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During the late nineteenth and early twentieth centuries, arsenic was used as an embalming agent in the United States. In 1996, Konefes and McGee brought the potential danger of arsenic poisoning during excavation to the attention of archaeologists. They developed methodology that was later refined by the present authors. This article discusses the history of arsenic as an embalming agent, explores socioeconomic and demographic factors that might suggest the presence of arsenic in certain burials, and presents methods for testing arsenic in archaeological contexts. We also discuss environmental impact mitigation considerations and review examples of arsenic testing in archaeological contexts.
Despite the strong link between childhood maltreatment and psychopathology, the underlying neurodevelopmental mechanisms are poorly understood and difficult to disentangle from heritable and prenatal factors. This study used a translational macaque model of infant maltreatment in which the adverse experience occurs in the first months of life, during intense maturation of amygdala circuits important for stress and emotional regulation. Thus, we examined the developmental impact of maltreatment on amygdala functional connectivity (FC) longitudinally, from infancy through the juvenile period. Using resting state functional magnetic resonance imaging (MRI) we performed amygdala–prefrontal cortex (PFC) region-of-interest and exploratory whole-brain amygdala FC analyses. The latter showed (a) developmental increases in amygdala FC with many regions, likely supporting increased processing of socioemotional-relevant stimuli with age; and (b) maltreatment effects on amygdala coupling with arousal and stress brain regions (locus coeruleus, laterodorsal tegmental area) that emerged with age. Maltreated juveniles showed weaker FC than controls, which was negatively associated with infant hair cortisol concentrations. Findings from the region-of-interest analysis also showed weaker amygdala FC with PFC regions in maltreated animals than controls since infancy, whereas bilateral amygdala FC was stronger in maltreated animals. These effects on amygdala FC development may underlie the poor behavioral outcomes associated with this adverse experience.
Additive manufacturing is a revolutionary three-dimensional (3D) printing technology that has applications in a vast number of fields from aerospace to biological engineering. In the field of bioengineering, it was recently discovered that the principles used in 3D bioprinting of organs and tissues could also be used to 3D print biological materials produced by genetically engineered bacteria. This new technology requires the development of modified bio-ink and optimized printing parameters to promote bacterial physiology while allowing printability. In this article, we highlight the recent advancements in additive manufacturing of engineered living materials using bacteria and their potential applications. We will discuss recent progress and significance of additive manufacturing of proteins and polypeptides produced in situ by engineered bacteria to make multifunctional materials. Finally, we discuss the challenges and prospects of this technology and highlight some of the biomaterials that may benefit from additive manufacturing with bacteria.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Determination of antibodies against ToRCH antigens at the beginning of pregnancy allows assessment of both the maternal immune status and the risks to an adverse pregnancy outcome. Age-standardised seroprevalences were determined in sera from 1009 women of childbearing age residing in Mexico, Brazil, Germany, Poland, Turkey or China using a multiparametric immunoblot containing antigen substrates for antibodies against Toxoplasma gondii, rubella virus, cytomegalovirus (CMV), herpes simplex viruses (HSV-1, HSV-2), Bordetella pertussis, Chlamydia trachomatis, parvovirus B19, Treponema pallidum and varicella zoster virus (VZV). Seroprevalences for antibodies against HSV-1 were >90% in samples from Brazil and Turkey, whereas the other four countries showed lower mean age-adjusted seroprevalences (range: 62.5–87.9%). Samples from Brazilian women showed elevated seroprevalences of antibodies against HSV-2 (40.1%), C. trachomatis (46.8%) and B. pertussis (56.6%) compared to the other five countries. Seroprevalences of anti-T. gondii antibodies (0.5%) and anti-parvovirus B19 antibodies (7.5%) were low in samples from Chinese women, compared to the other five countries. Samples from German women revealed a low age-standardised seroprevalence of anti-CMV antibodies (28.8%) compared to the other five countries. These global differences in immune status of women in childbearing age advocate country-specific prophylaxis strategies to avoid infection with ToRCH pathogens.
The COVID-19 pandemic forced American medical systems to adapt to high patient loads of respiratory disease. Its disruption of normal routines also brought opportunities for broader reform. The purpose of this article is to describe how the Carl R. Darnall Army Medical Center (CRDAMC), a medium-sized Army hospital, capitalized on opportunities to advance its strategic aims during the pandemic. Specifically, the hospital sequentially adopted virtual video visits, surged on preventative screenings, and made-over its image to appeal to patients seeking urgent care. These campaigns supported COVID-19 efforts and larger strategic goals simultaneously – and they will endure for years to come. Predictably, CRDAMC encountered obstacles in the course of its transformation. These obstacles and their follow-on lessons are provided to assist future medical leaders seeking quantum change in the opportunities made available by health crises.
A new high time resolution observing mode for the Murchison Widefield Array (MWA) is described, enabling full polarimetric observations with up to
$30.72\,$
MHz of bandwidth and a time resolution of
${\sim}$
$0.8\,\upmu$
s. This mode makes use of a polyphase synthesis filter to ‘undo’ the polyphase analysis filter stage of the standard MWA’s Voltage Capture System observing mode. Sources of potential error in the reconstruction of the high time resolution data are identified and quantified, with the
$S/N$
loss induced by the back-to-back system not exceeding
$-0.65\,$
dB for typical noise-dominated samples. The system is further verified by observing three pulsars with known structure on microsecond timescales.
The purpose of this study was to evaluate whether loss of consciousness (LOC), retrograde amnesia (RA), and anterograde amnesia (AA) independently influence a particular aspect of post-concussion cognitive functioning—across-test intra-individual variability (IIV), or cognitive dispersion.
Method:
Concussed athletes (N = 111) were evaluated, on average, 6.04 days post-injury (SD = 5.90; Mdn = 4 days; Range = 1–26 days) via clinical interview and neuropsychological assessment. Primary outcomes of interest included two measures of IIV—an intra-individual standard deviation (ISD) score and a maximum discrepancy (MD) score—computed from 18 norm-referenced variables.
Results:
Analyses of covariance (ANCOVAs) adjusting for time since injury and sex revealed a significant effect of LOC on the ISD (p = .018, ηp2 = .051) and MD (p = .034, ηp2 = .041) scores, such that athletes with LOC displayed significantly greater IIV than athletes without LOC. In contrast, measures of IIV did not significantly differ between athletes who did and did not experience RA or AA (all p > .05).
Conclusions:
LOC, but not RA or AA, was associated with greater variability, or inconsistencies, in cognitive performance acutely following concussion. Though future studies are needed to verify the clinical significance of these findings, our results suggest that LOC may contribute to post-concussion cognitive dysfunction and may be a risk factor for less efficient cognitive functioning.
A subcommittee of the Hawaii Governor's Joint Task Force on Rat Lungworm Disease developed preliminary guidelines for the diagnosis and treatment of neuroangiostrongyliasis (NAS) in 2018 (Guidelines, 2018). This paper reviews the main points of those guidelines and provides updates in areas where our understanding of the disease has increased. The diagnosis of NAS is described, including confirmation of infection by real-time polymerase chain reaction (RTi-PCR) to detect parasite DNA in the central nervous system (CNS). The treatment literature is reviewed with recommendations for the use of corticosteroids and the anthelminthic drug albendazole. Long-term sequelae of NAS are discussed and recommendations for future research are proposed.
We describe system verification tests and early science results from the pulsar processor (PTUSE) developed for the newly commissioned 64-dish SARAO MeerKAT radio telescope in South Africa. MeerKAT is a high-gain (
${\sim}2.8\,\mbox{K Jy}^{-1}$
) low-system temperature (
${\sim}18\,\mbox{K at }20\,\mbox{cm}$
) radio array that currently operates at 580–1 670 MHz and can produce tied-array beams suitable for pulsar observations. This paper presents results from the MeerTime Large Survey Project and commissioning tests with PTUSE. Highlights include observations of the double pulsar
$\mbox{J}0737{-}3039\mbox{A}$
, pulse profiles from 34 millisecond pulsars (MSPs) from a single 2.5-h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR
$\mbox{J}0540{-}6919$
, and nulling identified in the slow pulsar PSR J0633–2015. One of the key design specifications for MeerKAT was absolute timing errors of less than 5 ns using their novel precise time system. Our timing of two bright MSPs confirm that MeerKAT delivers exceptional timing. PSR
$\mbox{J}2241{-}5236$
exhibits a jitter limit of
$<4\,\mbox{ns h}^{-1}$
whilst timing of PSR
$\mbox{J}1909{-}3744$
over almost 11 months yields an rms residual of 66 ns with only 4 min integrations. Our results confirm that the MeerKAT is an exceptional pulsar telescope. The array can be split into four separate sub-arrays to time over 1 000 pulsars per day and the future deployment of S-band (1 750–3 500 MHz) receivers will further enhance its capabilities.
Introduction: Inhaled toxins from tobacco smoking, cannabis leaf smoking as well as vaping/e-cigarette products use are known causes of cardio-respiratory injury. While tobacco smoking has decreased among Canadian adults, there are now several other forms of legal inhalant products. While legal, the evidence of benefit and safety of vaping is limited. Of concern, cases of e-cigarette or vaping products use associated lung injury (EVALI) have been accumulating in the U.S. and now in Canada. Despite this, very little is known about the inhalation exposure of emergency department (ED) patients; this study was designed to explore lung health in the ED. Methods: We investigated the prevalence of exposure to vaping, tobacco and cannabis among patients presenting to a Canadian ED from July to November 2019. Ambulatory (CTAS 2 to 5), stable, adult (≥ 17 years) patients were prospectively identified and invited to complete a survey addressing factors related to lung health (previous diagnosis of respiratory conditions and respiratory symptoms at the ED presentation) and information on current exposure to vaping, tobacco and cannabis smoking. Categorical variables are reported as frequencies and percentages; continuous variables are reported as medians with interquartile range (IQR). The study was approved by the Health Research Ethics Board. Results: Overall, 1024 (71%) of 1433 eligible patients completed the survey. The median age was 43.5 (IQR: 29, 60), and 51% were female. A total of 351 (31%) participants reported having been previously diagnosed with ≥1 respiratory conditions, and 177 (17%) were visiting the ED as a result of ≥1 respiratory symptoms (e.g., cough, shortness of breath, wheezing). Daily tobacco smoking was reported by 190 (19%), and 83 (8%) reported using vaping/e-cigarette products. Cannabis use within 30 days was described by 80 (15%) respondents. Exposure to tobacco and vaping products was reported by 39 (4%) participants, 63 (6%) reported using tobacco in combination with cannabis smoking, and 3% reported combining vaping and cannabis use. Conclusion: Patients seeking care in the ED are exposed to a large quantity of inhaled toxins. Vaping products, considered the cause of the most recent epidemic of severe lung injury, are used in isolation and in combination with other smoking products in Canada. These exposures should be documented and may increase the risk of lung health injuries and exacerbations of chronic respiratory conditions.
Introduction: Hyperkalemia is a common electrolyte disturbance associated with morbidity and mortality. Commonly used therapies for hyperkalemia include IV calcium, sodium bicarbonate, insulin, beta-adrenergic agents, ion-exchange resins, diuretics and hemodialysis. This study aims to evaluate which treatments are more commonly used to treat hyperkalemia and to examine factors which influence those clinical decisions. Methods: This is a retrospective chart review of all cases of hyperkalemia encountered in 2017 at a Canadian adult ED. Potassium values were classified as mild (5.5 - 6.5 mEq/L), moderate (>6.5 - 7.5 mEq/L) and severe (>7.5 mEq/L). Treatment choices were then recorded and matched to hemodynamic stability, degree of hyperkalemia and ECG findings. More statistical methods to test correlation between treatment and specific variables will be performed over the next 2 months, including logistic regression to highlight potential determinants of treatment and Chi-square tests to verify randomness and to construct 95% confidence intervals. Results: 1867 ED visits were identified, of which 479 met the inclusion criteria. 89.1% of hyperkalemia cases were mild, 8.2% were moderate, and 2.7% were severe. IV insulin was used in 22.1% of cases, followed by Kayexalate in 20.5%, sodium bicarbonate in 12.3%, IV calcium in 9.4%, frusemide in 7.3%, salbutamol in 2.7%, and dialysis in 1.9%. Moderate and severe hyperkalemia were associated with higher use of insulin (79.5% and 64.3% respectively), IV calcium (41% and 64.3% respectively), sodium bicarbonate (56.4% and 85.7% respectively). Bradycardia was associated with higher insulin and IV calcium use (46.7% and 33.3% respectively). Hypotension was associated with a similar increase in use of insulin and IV calcium (34.2% and 23.7% respectively). There were only 15 cases of cardiac arrest in which sodium bicarbonate and IV calcium were more frequently used (80% and 60% respectively). Conclusion: This study demonstrates variability in the ED management of hyperkalemia. We found that Insulin and Kayexalate were the 2 most common interventions, with degree of hyperkalemia, bradycardia and hypotension influencing rates of treatment. Overuse of kayexalate for emergent treatment of hyperkalemia is evident despite weak supporting evidence. Paradoxically, beta adrenergic agents were underutilized despite their rapid effect and safer profile. The development of a widely accepted guideline may help narrow the differences in practice and potentially improve outcomes.
Introduction: Despite being legal in Canada, the vaporized liquid of vaping systems contains several chemicals presenting unknown risks to lung health and little is known about their use in patients visiting the emergency department (ED). This study explores associations between exposure to inhaled products and respiratory presentations in the ED. Methods: A cross-sectional lung health survey among patients presenting to a Canadian ED was conducted, exploring the association between inhaled toxic exposures (e.g., vaping, cannabis and cigarette smoking) and visits related to respiratory symptoms. Eligible participants were ambulatory (CTAS 2 to 5), stable, adults (≥ 17 years) visiting the ED from July to November, 2019. Results are described as frequencies and percentages (categorical variables) and medians with interquartile range (IQR, continuous variables). Univariate and multivariate logistic regression models report associations as odds ratios (OR) with 95% confidence intervals (CIs). The Health Research Ethics Board approved the study. Results: From 1433 eligible patients, 1024 (71%) completed the survey. The median age was 43.5 (IQR: 29, 60), and 51% were female. Overall, 177 (17%) reported ≥1 respiratory symptoms and 83 (8%) reported using any vaping products. In a univariate regression analysis, exposure to vaping was positively associated with ED visits related to respiratory symptoms (OR 2.11, 95% CI: 1.26 to 3.54). In the multivariate model, vaping and a previous diagnosis of ≥1 respiratory conditions showed positive association with respiratory-related ED visits (OR 1.86, 95% CI: 1.03 to 3.33; and OR 2.13, 95% CI: 1.50 to 3.02, respectively). There was evidence of an additive effect of the combined exposure to cigarettes and vaping and respiratory-related ED visits (OR 3.22, 95% CI: 1.61 to 6.43). Smoking cannabis and cigarettes alone were not associated with increased risk of respiratory-related visits. Conclusion: Using vaping products increased the occurrence of respiratory-related ED visits, particularly in people with pre-existing lung conditions. A dose-response relationship exists where the risk is highest in patients inhaling a combination of toxins. Contrary to previous assumptions, the use of vaping products has a negative impact on lung health.
Pottery Mound is a large Ancestral Puebloan site situated within the Middle Rio Grande (MRG) region of New Mexico. This article adds to our understanding of relationships between Pottery Mound, the Western Pueblos, and Mexico through use of biological distance analysis based on dental nonmetric traits. Extensive material and cultural influences, as well as migration events from Western Pueblos to Pottery Mound, have been proposed by several scholars, while others have highlighted parallels to Mexico, especially Paquimé. A total of 1,528 individuals from the U.S. Southwest and Mexico were used to examine relationships between Pottery Mound and these areas. We find no evidence of close biological similarity between Pottery Mound and the Western Pueblos or northern Mexico. Instead, the results indicate biological affinity between Pottery Mound and sites in the MRG region and Mogollon areas. This similarity suggests that although there is evidence for trade between Pottery Mound and other sites in the southwestern United States and Mesoamerica, trade may not have been accompanied by significant gene flow from those areas from which the trade goods originated. It is possible that neighboring regions, such as the Mogollon, served as intermediaries for trade between Pottery Mound and distant regions.
A growing interest in dielectric waveguides (DWGs) as an alternative to commonly used waveguides (like coaxial or twisted-pair cables) for high data rate interconnects could be observed in the last few years. Especially in the mm-wave frequency range (30–300 GHz) applications with these waveguides benefit from low losses and low dispersion. Moreover, using both polarizations of the fundamental mode in such waveguides could theoretically double the data rate without the need of higher bandwidth or additional fibers. The connection between DWGs and commonly available transceiver chips requires broadband transitions from planar waveguides like microstrip lines to DWGs. In this paper, an overview of the current developments of such transitions is given and a novel low-complexity design is presented that reduces the space consumption by 35% related to recently published works. This allows an easy integration into a printed circuit board layout or a chip package. Furthermore, an extensive sensitivity analysis is presented to prove the robustness toward manufacturing tolerances. The transition is realized at W-band frequencies (75–110 GHz) and achieves a relative 10 dB-bandwidth of more than 25% with a minimum insertion loss of 1.2 dB. It is shown that these properties even hold for manufacturing tolerances of nowadays manufacturing processes.
DTNBP1, which encodes dysbindin-1, is one of the best-supported susceptibility genes for schizophrenia, and hippocampal volume reduction is one of the major neuropathological findings in schizophrenia. Consistent with these findings, dysbindin-1 has been shown to be diminished in glutamatergic hippocampal neurons in schizophrenic patients. The aim of this study was to directly investigate the effects of two single nucleotide polymorphisms of the DTNBP1 gene on regional brain volumes in human subjects.
Methods
128 subjects participated in the study. All subjects were genotyped with respect to two single nucleotide polymorphisms of the DTNBP1 gene (rs2619522 and rs1018381) and underwent structural magnetic resonance imaging (MRI). MRI data were preprocessed and statistically analyzed using standard procedures as implemented in SPM5, in particular the voxel-based morphometry (VBM) toolbox.
Results
We found significant effects of the DTNBP1-SNP rs2619522 on regional brain volumes bilaterally in the hippocampus as well as in the anterior middle frontal gyrus and the intraparietal cortex. T/T homozygotes showed significantly lower grey matter volumes in these brain regions than carriers of the G allele.
Conclusions
Compatible with previous findings on a role of the dysbindin-1 gene in hippocampal functions as well as in major psychoses, the present study provides first direct in-vivo evidence that the DTNBP1-SNP rs2619522 is associated with variation of grey matter volumes bilaterally in the human hippocampus.
Ecstasy (3,4-methylenedioxymethamphetamine, MDMA) is an amphetamine derivative that is used recreationally and is now being tested in clinical trials for treatment of posttraumatic stress disorder. Ecstasy can damage serotonin neurones in brain of experimental animals; however, relevance of these findings to the human is debated.
Aim:
To measure by positron emission tomography (PET) levels of binding to the serotonin transporter (SERT), a marker of serotonin neurones, in brain of chronic ecstasy users and in matched controls.
Methods:
An estimate of brain SERT levels was obtained, using the PET tracer 11C-DASB, in 50 chronic (confirmed by drug hair testing) ecstasy users (mean age, 26 years; mean duration of drug use, 3.9 years; median drug withdrawal time, 38 days) and 50 (drug-hair negative) control subjects (mean age 26 years).
Results:
SERT binding levels in the ecstasy group were significantly decreased by 22 to 46% in frontal, temporal, cingulate, insular and occipital cortices, and by 23% in hippocampus. However, concentrations were distinctly normal in the SERT-rich caudate, putamen, ventral striatum and thalamus.
Conclusion:
Our imaging data suggest that cerebral cortical SERT concentration is below normal in some ecstasy users for at least one month after last use of the drug. However, it remains to be established whether low SERT might have preceded drug use, reflects actual loss of brain serotonin neurones, or is causally related to any functional impairment in the ecstasy users. (Supported by US NIH NIDA DA017301).
Many experience low mood and energy during winter. Brain serotonin is involved in the regulation of many physiologic and pathologic functions that vary with season. Seasonal variations in peripheral serotonergic markers have been described in clinical and nonclinical populations, and a postmortem study shows seasonal differences in hypothalamic serotonin concentration.
Aim
We investigated the molecular background of seasonal changes in serotonin function by conducting a series of studies on serotonin transporter (5-HTT) density and function in depression and health.
Methods
In a large study in drug-free patients with seasonal affective disorder (SAD) we aimed at detecting state-related alterations in 5-HTT-mediated inward and outward transport in platelets. Another study in healthy subjects aimed at detecting seasonal variations in 5-HTT binding in the living human brain using [11C] DASB positron emission tomography. Regional 5-HTT binding, an index of 5-HTT density, was assessed in a large sample of drug-naïve healthy volunteers, and was related to meteorological and astronomical data.
Results
In patients with SAD we showed that the 5-HTT is in a hyperfunctional state during winter depression, and normalizes after light therapy and in natural summer remission. In healthy subjects, 5-HTT binding was higher in autumn/winter as compared to spring/summer. Regional 5-HTT binding correlated negatively with daily sunshine, such that higher values occurred at times of lesser light.
Conclusions
Since high 5-HTT density is associated with low synaptic serotonin levels, regulation of 5-HTT density and 5-HTT function by light is a mechanism that may explain seasonal changes in normal and pathologic behaviours.