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We report infrared reflectance and ultraviolet fluorescence spectra of the surfaces and cleaved side of Beacon Sandstone from Antarctica that harbours a cryptoendolithic microbial community - a photosynthesis-based consortium of algae, lichen and bacteria present a few millimetres below the surface. Chlorophyll absorptions were present in the reflectance spectra of the exposed interior but not on the top or bottom surfaces and their band depths changed < 4% between measurements taken 19 years apart, indicating the stability of the microorganisms when the sample is kept dry. The presence of subsurface organic layers was detected in reflectance at 3.41 μm on the sample's surface. Fluorescence spectra of the cleaved side showed the blue fluorescence peaks expected from chlorophyll but no 0.65–0.80 μm peaks seen in fluorescence measurements of green vegetation. A weak fluorescence signal was detectable at the surface of the sample, presumably due to some light leaking into the subsurface through pores or cracks in the goethite coating the sample's surface. Theoretically, this weak fluorescence signal could possibly be observed in rock surfaces broken by erosion or meteor impacts on Mars. Sandstone outcrops have been reported on Mars and detection of organic layers in sandstones there would be of interest.
Weedy rice (WR) (Oryza sativa L.) is the most troublesome weed infesting rice paddies in Brazil. Several changes have occurred in this region regarding crop management, especially WR control based on the Clearfield™ (CL) Rice Production System launched in 2003. This survey’s objective was to evaluate the WR infestation status by assessing the producers’ perception and the management practices used in southern Brazil after eighteen years of CL use in Brazil. Rice consultants and extension agents distributed a questionnaire with 213 producers in the Rio Grande do Sul (RS) and Santa Catarina (SC) state in the 2018/19 growing season. In RS, most farms are larger than 150 ha, farmers use minimal or conventional tillage, permanent flooding, adopted the CL system for more than two years, use clomazone PRE tank-mixed with glyphosate at the rice spiking stage, and use crop rotation with soybean [Glycine max (L.) Merr.] or pasture. In SC, rice farms are small, averaging from 20 to 30 ha, farmers predominantly plant pre-germinated rice and do not rotate rice with other crops and roguing is practiced. Comparing both states, the CL System is used in 99.5, and 69.3% of the total surveyed rice area in RS and SC, respectively. Imidazolinone-resistant WR is present in 68.4 and 26.6% of rice farms in RS and SC, respectively. Rice cultivation in Brazil is currently coexisting with WR with minimal integration of control methods. However, integrated practices can control this weed and are fundamental to the sustainability of systems based on herbicide-resistant rice cultivars.
Cognitive impairment is common in bipolar disorder and is emerging as a therapeutic target to enhance quality of life and function. A systematic search was conducted on PubMed, PsycInfo, Cochrane, clinicaltrials.gov, and Embase databases for blinded or open-label randomized controlled trials evaluating the pro-cognitive effects of pharmacological, neurostimulation, or psychological interventions for bipolar disorder. Twenty-two trials were identified, evaluating a total of 16 different pro-cognitive interventions. The methodological quality of the identified trials were assessed using the Cochrane Risk of Bias tool. Currently, no intervention (i.e., pharmacologic, neurostimulation, cognitive remediation) has demonstrated robust and independent pro-cognitive effects in adults with bipolar disorder. Findings are preliminary and methodological limitations limit the interpretation of results. Methodological considerations including, but not limited to, the enrichment with populations with pre-treatment cognitive impairment, as well as the inclusion of individuals who are in remission are encouraged. Future trials may also consider targeting interventions to specific cognitive subgroups and the use of biomarkers of cognitive function.
Subanesthetic ketamine infusion therapy can produce fast-acting antidepressant effects in patients with major depression. How single and repeated ketamine treatment modulates the whole-brain functional connectome to affect clinical outcomes remains uncharacterized.
Methods
Data-driven whole brain functional connectivity (FC) analysis was used to identify the functional connections modified by ketamine treatment in patients with major depressive disorder (MDD). MDD patients (N = 61, mean age = 38, 19 women) completed baseline resting-state (RS) functional magnetic resonance imaging and depression symptom scales. Of these patients, n = 48 and n = 51, completed the same assessments 24 h after receiving one and four 0.5 mg/kg intravenous ketamine infusions. Healthy controls (HC) (n = 40, 24 women) completed baseline assessments with no intervention. Analysis of RS FC addressed effects of diagnosis, time, and remitter status.
Results
Significant differences (p < 0.05, corrected) in RS FC were observed between HC and MDD at baseline in the somatomotor network and between association and default mode networks. These disruptions in FC in MDD patients trended toward control patterns with ketamine treatment. Furthermore, following serial ketamine infusions, significant decreases in FC were observed between the cerebellum and salience network (SN) (p < 0.05, corrected). Patient remitters showed increased FC between the cerebellum and the striatum prior to treatment that decreased following treatment, whereas non-remitters showed the opposite pattern.
Conclusion
Results support that ketamine treatment leads to neurofunctional plasticity between distinct neural networks that are shown as disrupted in MDD patients. Cortico-striatal-cerebellar loops that encompass the SN could be a potential biomarker for ketamine treatment.
To assess influenza symptoms, adherence to mask use recommendations, absenteesm and presenteeism in acute care healthcare workers (HCWs) during influenza epidemics.
Methods:
The TransFLUas influenza transmission study in acute healthcare prospectively followed HCWs prospectively over 2 consecutive influenza seasons. Symptom diaries asking for respiratory symptoms and adherence with mask use recommendations were recorded on a daily basis, and study participants provided midturbinate nasal swabs for influenza testing.
Results:
In total, 152 HCWs (65.8% nurses and 13.2% physicians) were included: 89.1% of study participants reported at least 1 influenza symptom during their study season and 77.8% suffered from respiratory symptoms. Also, 28.3% of HCW missed at least 1 working day during the study period: 82.6% of these days were missed because of symptoms of influenza illness. Of all participating HCWs, 67.9% worked with symptoms of influenza infection on 8.8% of study days. On 0.3% of study days, symptomatic HCWs were shedding influenza virus while at work. Among HCWs with respiratory symptoms, 74.1% adhered to the policy to wear a mask at work on 59.1% of days with respiratory symptoms.
Conclusions:
Respiratory disease is frequent among HCWs and imposes a significant economic burden on hospitals due to the number of working days lost. Presenteesm with respiratory illness, including influenza, is also frequent and poses a risk for patients and staff.
Hookworms are some of the most widespread of the soil-transmitted helminths (STH) with an estimated 438.9 million people infected. Until relatively recently Ancylostoma ceylanicum was regarded as a rare cause of hookworm infection in humans, with little public health relevance. However, recent advances in molecular diagnostics have revealed a much higher prevalence of this zoonotic hookworm than previously thought, particularly in Asia. This study examined the prevalence of STH and A. ceylanicum in the municipalities of Palapag and Laoang in the Philippines utilizing real-time polymerase chain reaction (PCR) on stool samples previously collected as part of a cross-sectional survey of schistosomiasis japonica. Prevalence of hookworm in humans was high with 52.8% (n = 228/432) individuals positive for any hookworm, 34.5% (n = 149/432) infected with Necator americanus, and 29.6% (n = 128/432) with Ancylostoma spp; of these, 34 were PCR-positive for A. ceylanicum. Considering dogs, 12 (n = 33) were PCR-positive for A. ceylanicum. This is the first study to utilize molecular diagnostics to identify A. ceylanicum in the Philippines with both humans and dogs infected. Control and elimination of this zoonotic hookworm will require a multifaceted approach including chemotherapy of humans, identification of animal reservoirs, improvements in health infrastructure, and health education to help prevent infection.
Purpose: The novel coronavirus (severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)) first appeared in Wuhan, China, in December 2019, and rapidly spread across the globe. Since most respiratory viruses are known to show a seasonal pattern of infection, it has been hypothesised that SARS-CoV-2 may be seasonally dependent as well. The present study looks at a possible effect of atmospheric temperature, which is one of the suspected factors influencing seasonality, on the evolution of the pandemic. Basic procedures: Since confirming a seasonal pattern would take several more months of observation, we conducted an innovative day-to-day micro-correlation analysis of nine outbreak locations, across four continents and both hemispheres, in order to examine a possible relationship between atmospheric temperature (used as a proxy for seasonality) and outbreak progression. Main findings: There was a negative correlation between atmospheric temperature variations and daily new cases growth rates, in all nine outbreaks, with a median lag of 10 days. Principal conclusions: The results presented here suggest that high temperatures might dampen SARS-CoV-2 propagation, while lower temperatures might increase its transmission. Our hypothesis is that this could support a potential effect of atmospheric temperature on coronavirus disease progression, and potentially a seasonal pattern for this virus, with a peak in the cold season and rarer occurrences in the summer. This could guide government policy in both the Northern and Southern hemispheres for the months to come.
Political theorists and philosophers have long been interested in the question of the legitimacy of political authority, where it comes from and how it may be maintained or improved, from both instrumental and ethical perspectives. Normally, such debates were focused upon the state and the fulcrum of power, legitimacy and authority. They then extended to the development of international institutions and law to cement the architectures of legitimacy at the state level.
Legitimacy within the state is generally taken to refer to the justification for rule, which has normative and sociological dimensions, the first pointing to the importance of standards and, the second, to beliefs. In an ideal situation, standards and beliefs are mutually reinforcing and populations consent to those who claim authority over them. At the international level, legitimacy rests on the general consent of states, international law and the capacity of any agreement, organisation or treaty to deliver its objectives. Both levels are concerned with inducing a ‘constitutional moment’ at national and international levels (the latter emerging through the UN system, different types of international law, and regional organisations such as the European Union or, alternatively, African Union). Security actors are closely connected to this evolution, such as NATO, along with the development of supranational forms of foreign policy. Connecting both perspectives has long been thought to represent a virtuous circle for an otherwise opaque and imprecise concept. Likewise, policymakers and scholars from around the world have recently become more interested in these matters, especially in the light of various interventions in the post-Cold War world, to bring about peace, development, and to build better states.
However, legitimacy is far from being vague or imprecise and it can be disaggregated across scales and issues with some precision according to normative conceptions of historical, distributive, and social justice in and between societies. Contradictions creep in when these various scales are connected into a united whole at state level, or a universal framework at international level, distorted by power relations. This radically re-orients traditional conceptions of state legitimacy and state–society relations in the mould of Hobbes, Rousseau or Locke, or efficiency, or even international law.
This edited volume focuses on disentangling the interplay of local peacebuilding processes and international policy, via comparative theoretical and empirical work on the question of legitimacy and authority.
The simple horizontal and vertical alignment of multiple legitimacies into common, central authorities as the basis for an evolved and ethical peace appears to be an oversimplification of a very complex process. Too much substance is lost in its simplification, as is well illustrated in Roger Mac Ginty and Kristina Tschunkert's chapter on Lebanon, which follows Boege’s deployment of hybridity in understanding the realities of legitimate authority in modern conflict-affected societies. Visoka's chapter on Kosovo underlines the relationality of contemporary legitimate authority, something which peacebuilding has mostly missed, and all of the other chapters confirm variations of this theme. Much of this argumentation indicates that effective peacebuilding needs to understand the special complexities of relational political legitimacy across life-worlds and levels of analysis far better if it is to be more successful. A localised view of legitimacy creates a number of different and contradictory demands in the context of the nature of the state and its performance, as well as towards the international community. These point beyond the usual understandings of modern legitimacy emanating from civil society and within a liberal social contract, which may be weakly extended to international institutions and law, however, including the balancing of social justice and human rights with identity, long-standing institutions, patterns of authority and law.
It is clear that social legitimacy – perhaps linked to kinship, religion or identity – is not always aligned with the state or with international norms. Yet, international actors have intervened in the post-Cold War environment as if local and state forms of legitimacy authority should be aligned with international law and norms. Indeed, enormous efforts have been made by international actors in multiple contexts to try to train, mentor and encourage local forms of legitimacy to adapt to internationally-recognised forms. This institutional isomorphism seems to have failed to recognise that different types of legitimacy are at work in different domains and that all of them contribute to a complex assemblage of power, legitimacy, patronage and logics. The empirical evidence amassed so far shows that convergence is an unlikely goal, if not impossible, and that in fact the multiple forms of legitimacy at work in post-war contexts normally diverge. This implies that legitimacy is likely to rest on a divergence rather than convergence between custom, practice, national or international law, a very tricky proposition indeed for any rationality-based international order.
Site-selectivity analysis of drilling predation traces may provide useful behavioral information concerning a predator interacting with its prey. However, traditional approaches exclude some spatial information (i.e., oversimplified trace position) and are dependent on the scale of analysis (e.g., arbitrary grid system used to divide the prey skeleton into sectors). Here we introduce the spatial point pattern analysis of traces (SPPAT), an approach for visualizing and quantifying the distribution of traces on shelled invertebrate prey, which includes improved collection of spatial information inherent to drillhole location (morphometric-based estimation), improved visualization of spatial trends (kernel density and hotspot mapping), and distance-based statistics for hypothesis testing (K-, L-, and pair correlation functions). We illustrate the SPPAT approach through case studies of fossil samples, modern beach-collected samples, and laboratory feeding trials of naticid gastropod predation on bivalve prey. Overall results show that kernel density and hotspot maps enable visualization of subtle variations in regions of the shell with higher density of predation traces, which can be combined with the maximum clustering distance metric to generate hypotheses on predatory behavior and anti-predatory responses of prey across time and geographic space. Distance-based statistics also capture the major features in the distribution of traces across the prey skeleton, including aggregated and segregated clusters, likely associated with different combinations of two modes of drilling predation, edge and wall drilling. The SPPAT approach is transferable to other paleoecologic and taphonomic data such as encrustation and bioerosion, allowing for standardized investigation of a wide range of biotic interactions.
Introduction: The legalization of cannabis for recreational use in 2018 remains a controversial topic. There are multiple perceived benefits of cannabis including pain relief, treatment of epilepsy syndromes, and improving body weight of cancer patients. However, there are also many potential risks. The short-term health consequences include cannabinoid hyperemesis syndrome and cannabis induced psychosis. These conditions directly impact the influx of patients presenting to Emergency Departments (ED). There is currently limited research in the area of cannabis legalization burden. However, the studies performed have shown a significant impact in those states which cannabis is legal. A study completed in Colorado found that hospitalization rates with marijuana related billing codes increased from 274 to 593 per 100 000 hospitalizations after the state legalization of recreational cannabis. This study aims to examine if Canada's hospitals are experiencing the same burden as other jurisdictions. Methods: A descriptive study was preformed via a retrospective chart review of cannabis related visits in tertiary EDs in St. John's, NL, from six months prior to the date of legalization of cannabis for recreational use, to six months after. Hospital ED visit records from both the Health Science Centre and St. Clare's Mercy Hospital were searched using keywords to identify patients who presented with symptoms related to cannabis use. We manually reviewed all visit records that included one or more of these terms to distinguish true positives from false positive cases, unrelated to cannabis use. Results: A total of 287 charts were included in the study; 123 visits were related to cannabis use six months prior to legalization, and 164 six months after legalization. A significant increase in ED visits following the legalization of recreational cannabis was seen (p < .001). There was no significant difference in the age of users between the two groups. Additionally, the number one presenting complaint due to cannabis use was vomiting (47.7%), followed by anxiety (12.2%). Conclusion: Following the implementation of the Cannabis Act in Canada, EDs in St. John's, NL had a statistically significant increase in the number of visits related to cannabis use. It is important to determine such consequences to ensure hospitals and public health agencies are prepared to treat the influx of visits and are better equipped to manage the associated symptoms.
We present a detailed analysis of the radio galaxy PKS
$2250{-}351$
, a giant of 1.2 Mpc projected size, its host galaxy, and its environment. We use radio data from the Murchison Widefield Array, the upgraded Giant Metre-wavelength Radio Telescope, the Australian Square Kilometre Array Pathfinder, and the Australia Telescope Compact Array to model the jet power and age. Optical and IR data come from the Galaxy And Mass Assembly (GAMA) survey and provide information on the host galaxy and environment. GAMA spectroscopy confirms that PKS
$2250{-}351$
lies at
$z=0.2115$
in the irregular, and likely unrelaxed, cluster Abell 3936. We find its host is a massive, ‘red and dead’ elliptical galaxy with negligible star formation but with a highly obscured active galactic nucleus dominating the mid-IR emission. Assuming it lies on the local M–
$\sigma$
relation, it has an Eddington accretion rate of
$\lambda_{\rm EDD}\sim 0.014$
. We find that the lobe-derived jet power (a time-averaged measure) is an order of magnitude greater than the hotspot-derived jet power (an instantaneous measure). We propose that over the lifetime of the observed radio emission (
${\sim} 300\,$
Myr), the accretion has switched from an inefficient advection-dominated mode to a thin disc efficient mode, consistent with the decrease in jet power. We also suggest that the asymmetric radio morphology is due to its environment, with the host of PKS
$2250{-}351$
lying to the west of the densest concentration of galaxies in Abell 3936.
Ices of various compositions and in various phases and combinations with one another are found on planetary surfaces through remote sensing techniques, of which optical spectroscopy is the most powerful and diagnostic. Ices also are found in combination with minerals and organic materials; some complex organic materials are the result of energetic processing of ices, while some may represent organic matter from other sources. Remote spectroscopic observations from Earth-based telescopes and planetary probes are usually interpreted with the aid of radiative transfer models that account for the compositions, particle properties, mixing configurations and other parameters relevant to the materials under consideration. This chapter reviews the spectroscopic character of planetary ices in pure states and in combinations with one another, and with minerals and organic solid materials found by remote sensing techniques and by the analysis of analog materials, both naturally occurring and synthesized in the laboratory and thus available for analytical studies.
The Cassini Visual Infrared Mapping Spectrometer (VIMS) spans a wavelength range of 0.34 to 5.2 µm. Executing numerous close targeted flybys of the major moons of Saturn, as well as serendipitous flybys of the smaller moons, VIMS gathered millions of spectra of these bodies during its 13-year mission, some at spatial resolutions of a few hundred meters. The surfaces of the inner moons are dominated by water ice, while Iapetus, Hyperion, and Titan have substantial amounts of dark materials, including hydrocarbons, on their surfaces. Phoebe is grayer in color in the visible than Saturn’s other low-albedo moons. The surfaces of the inner small moons are also dominated by water ice, and they share compositional similarities to the main rings. The optical properties of the main moons are affected by particles from Saturn’s rings: the inner moons are coated by the E-ring, which originates from cryoactivity on Enceladus, while Iapetus and Hyperion are coated by particles from the Phoebe ring. Cassini VIMS detected previously unknown volatiles and organics on these moons, including CO2, H2, organic molecules as complex as aromatic hydrocarbons, nano-iron, and nano-iron oxides.
A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.