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Brine beneath Taylor Glacier has been proposed to enter the proglacial west lobe of Lake Bonney (WLB) as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the geochemistry of the water column of WLB. Year-round measurements from this study are the first to definitively identify brine intrusions from a subglacial entry point into WLB. Furthermore, we excluded input from Blood Falls by focusing on winter dynamics when the absence of an open water moat prevents surface brine entry. Due to the extremely high salinities below the chemocline in WLB, density stratification is dominated by salinity, and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude into the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. High-resolution measurements also reveal under-ice internal waves associated with katabatic wind events, a novel finding that challenges long-held assumptions about the stability of the WLB water column.
This study seeks to understand the low temperature reactions of the salt phase that occur during the vitrification of Hanford Low Activity Waste (LAW). Salts (such as nitrates, sulfates, carbonates, halides, etc.) play a key role in these low temperature reactions as they sequentially melt, decompose, and volatilize during batch-to-glass conversion. To further understand these complex processes, simplified LAW melts containing oxyanion salts (sodium salts of carbonate, sulfate, and/or nitrate) and early melting glass formers (boric acid) have been evaluated using thermal analysis, infrared absorption spectroscopy, and X-ray diffraction. Results from this study indicate that the volatilization behavior of particular salts is influenced by the presence or absence of other salts. NaNO3 volatilization is decreased by the presence of Na2SO4. The addition of either Na2SO4 or NaNO3 to the system may enhance the volatilization of Na2CO3. In all cases, Na2SO4 was retained after melting and was often found to be in two different crystalline phases upon quenching.
Late-life depression (LLD) is associated with poor social functioning. However, previous research uses bias-prone self-report scales to measure social functioning and a more objective measure is lacking. We tested a novel wearable device to measure speech that participants encounter as an indicator of social interaction.
Twenty nine participants with LLD and 29 age-matched controls wore a wrist-worn device continuously for seven days, which recorded their acoustic environment. Acoustic data were automatically analysed using deep learning models that had been developed and validated on an independent speech dataset. Total speech activity and the proportion of speech produced by the device wearer were both detected whilst maintaining participants' privacy. Participants underwent a neuropsychological test battery and clinical and self-report scales to measure severity of depression, general and social functioning.
Compared to controls, participants with LLD showed poorer self-reported social and general functioning. Total speech activity was much lower for participants with LLD than controls, with no overlap between groups. The proportion of speech produced by the participants was smaller for LLD than controls. In LLD, both speech measures correlated with attention and psychomotor speed performance but not with depression severity or self-reported social functioning.
Using this device, LLD was associated with lower levels of speech than controls and speech activity was related to psychomotor retardation. We have demonstrated that speech activity measured by wearable technology differentiated LLD from controls with high precision and, in this study, provided an objective measure of an aspect of real-world social functioning in LLD.
Continued reliance on chemical methods for controlling annual bluegrass has resulted in many populations evolving resistance to PRE and POST herbicides, particularly in warm-season turfgrass species such as zoysiagrass. Soil seedbank management is critically important when managing herbicide-resistant weeds. Fraise mowing (also spelled fraze, frase, and fraize) is a new turfgrass cultivation practice designed to remove aboveground biomass while allowing turf to regrow vegetatively. We hypothesized that this process would remove annual bluegrass seed and therefore be a mechanical means of controlling annual bluegrass in turfgrass. Zoysiagrass field plots were fraise-mowed in June 2015 only, June 2016 only, June 2015 and June 2016, or left untreated. The fraise mower was configured to remove the uppermost 25 mm of plot surface (i.e., 15-mm verdure and 10-mm soil). Annual bluegrass infestation was quantified in April following fraise mowing via grid count. Soil cores (10.8 cm diameter) were extracted from each plot after grid count data were collected to assess effects of fraise mowing on the soil seedbank. Moreover, replicated subsamples (7.6 L) of debris generated during fraise mowing were collected to better understand weed seed content removed during the fraise mowing process. Fraise mowing in June offered a slight reduction (24%) in annual bluegrass cover the following April. Whereas 28% of the seed in fraise-mowing debris consisted of annual bluegrass, there was no difference in the quantity of annual bluegrass seed remaining in the soil seedbank among fraise-mowed and non–fraise-mowed plots. Although fraise mowing may help to temporarily reduce existing annual bluegrass infestations via mechanical removal, the frequency and depth we studied did not effectively reduce the seedbank. Fraise mowing is a useful tool for providing mechanical suppression of annual bluegrass but it is not a replacement for properly timed herbicide applications.
Late Holocene sediment deposits in Pine Island Bay, West Antarctica, are hypothesized to be linked to intensive meltwater drainage during the retreat of the paleo-Pine Island Ice Stream after the Last Glacial Maximum. The uppermost sediment units show an abrupt transition from ice-proximal debris to a draped silt during the late Holocene, which is interpreted to coincide with rapid deglaciation. The small scale and fine sorting of the upper unit could be attributed to origins in subglacial meltwater; however the thickness and deposition rate for this unit imply punctuated- rather than continuous-deposition. This, combined with the deposit's location seaward of large, bedrock basins, has led to the interpretation of this unit as the result of subglacial lake outbursts in these basins. However, the fine-scale sorting of the silt unit is problematic for this energetic interpretation, which should mobilize and deposit a wider range of sediment sizes. To resolve this discrepancy, we present an alternative mechanism in which the silt was sorted by a distributed subglacial water system, stored in bedrock basins far inland of the grounding line, and subsequently eroded at higher flow speeds during retreat. We demonstrate that this mechanism is physically plausible given the subglacial conditions during the late Holocene. We hypothesize that similar silt units observed elsewhere in Antarctica downstream of bedrock basins could be the result of the same mechanism.
To estimate the effects of continuous daily treatment with different acid suppressants on the risk of ventilator-associated events in critically ill patients.
Retrospective cohort study.
Adult critically ill patients who underwent mechanical ventilation for ≥3 days during an inpatient admission between January 2006 and December 2014.
We estimated the 30-day cumulative risk ratios (RRs) for ventilator-associated events comparing daily proton pump inhibitor (PPI) versus daily histamine-2-receptor antagonist (H2RA) strategies while controlling for time-fixed and time-varying confounding and accounting for competing events.
Of 6,133 patients, on ventilation day 3, 58.8% received H2RAs, 26.1% received PPIs, and 4.1% received sucralfate. Patients frequently changed treatment throughout follow-up. Among 4,595 patients receiving PPIs or H2RAs on day 3, we found no differences in risk estimates for ventilator mortality and extubation alive comparing daily PPI versus daily H2RA strategies: RR, mortality, 1.03 (95% CI, 0.89–1.22); extubation alive, 1.00 (95% CI, 0.96–1.03). We found similar results after accounting for PPI dose. For possible ventilator-associated pneumonia (PVAP) and infection-related ventilator-associated complication (IVAC), point estimates were larger, but the 95% CIs crossed 1.0: RR PVAP, 1.25 (95% CI, 0.80–1.94); IVAC, 0.89 (95% CI, 0.64–1.17). The magnitude of effect estimates depended on PPI dose. The RR for PVAP, high-dose PPI versus H2RA, was 1.53 (95% CI, 0.82–2.51), and for low-dose PPI versus H2RA, the RR was 0.97 (95% CI, 0.47–1.63). For IVAC, high-dose PPI versus H2RA, the RR was 1.01 (95% CI, 0.66–1.42), and for low-dose PPI versus H2RA, the RR was 0.78 (95% CI, 0.50–1.11).
We estimated no effect of daily PPI versus daily H2RA on risk of mortality or extubation alive in critically ill patients. Further investigation with larger samples is warranted for PVAP and IVAC.
There is an emerging consensus in developmental psychopathology that irritable youth are at risk for developing internalizing problems later in life. The current study explored if irritability in youth is multifactorial and the impact of irritability dimensions on psychopathology outcomes in adulthood.
We conducted exploratory factor analysis on irritability symptom items from a semi-structured diagnostic interview administered to a community sample of adolescents (ages 14–19; 42.7% male; 89.1% white). The analysis identified two factors corresponding to items from the mood disorders v. the oppositional defiant disorder (ODD) (Leibenluft and Stoddard) sections of the interview. These factors were then entered together into regression models predicting psychopathology assessed at age 24 (N = 941) and again at age 30 (N = 816). All models controlled for concurrent psychopathology in youth.
The two irritability dimensions demonstrated different patterns of prospective relationships, with items from the ODD section primarily predicting externalizing psychopathology, items from the mood disorder sections predicting depression at age 24 but not 30, and both dimensions predicting borderline personality disorder symptoms.
These results suggest that the current standard of extracting and compositing irritability symptom items from diagnostic interviews masks distinct dimensions of irritability with different psychopathological outcomes. Additionally, these findings add nuance to the prevailing notion that irritability in youth is specifically linked to later internalizing problems. Further investigation using more sensitive and multifaceted measures of irritability are needed to parse the meaning and clinical implications of these dimensions.
From the start of the United States’ violent, forced participation in World War II until the present day, the culture of the US Navy transformed significantly several times. All of these “cultural revolutions” – if we may call them that – influenced how the Navy fought after World War II, in both hot wars and cold. The enduring context of the post–World War II environment was the absence of any overt, large-scale warfare on the seas between the US Navy and the navies of those nations it engaged in limited war (e.g., North Korea, North Vietnam, and Iran), as well as the Cold War with the Soviet Red Banner Fleet. This made assessing the impact of culture on war-fighting effectiveness difficult. It employs the analytical methods of Edgar Schein in looking at the components and dynamics of organizational culture. However, the impact of these cultural changes on the combat effectiveness of the Navy remains opaque given an entire generation has passed since the 1990s. More research remains to be done on how events since the terrorist attacks on the United States in 2001 changed the US Navy.
Spotted fever group rickettsiae (SFG) are a neglected group of bacteria, belonging to the genus Rickettsia, that represent a large number of new and emerging infectious diseases with a worldwide distribution. The diseases are zoonotic and are transmitted by arthropod vectors, mainly ticks, fleas and mites, to hosts such as wild animals. Domesticated animals and humans are accidental hosts. In Asia, local people in endemic areas as well as travellers to these regions are at high risk of infection. In this review we compare SFG molecular and serological diagnostic methods and discuss their limitations. While there is a large range of molecular diagnostics and serological assays, both approaches have limitations and a positive result is dependent on the timing of sample collection. There is an increasing need for less expensive and easy-to-use diagnostic tests. However, despite many tests being available, their lack of suitability for use in resource-limited regions is of concern, as many require technical expertise, expensive equipment and reagents. In addition, many existing diagnostic tests still require rigorous validation in the regions and populations where these tests may be used, in particular to establish coherent and worthwhile cut-offs. It is likely that the best strategy is to use a real-time quantitative polymerase chain reaction (qPCR) and immunofluorescence assay in tandem. If the specimen is collected early enough in the infection there will be no antibodies but there will be a greater chance of a PCR positive result. Conversely, when there are detectable antibodies it is less likely that there will be a positive PCR result. It is therefore extremely important that a complete medical history is provided especially the number of days of fever prior to sample collection. More effort is required to develop and validate SFG diagnostics and those of other rickettsial infections.
It is the confluence of three human agency trends – planetary urbanism, resource scarcity and climate change – that will have a profound impact on the manner in which we occupy and relate to the planet and each other. This confluence is unparalleled in world history. We are entering unknown territory with little knowledge as to how these three trends will interact in complex, unpredictable and unprecedented ways. However, we do know that this confluence is upon us and it will continue to create a NEW DESIGN CONDITION to which we as a planetary community need to respond.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Although behavior therapy reduces tic severity, it is unknown whether it improves co-occurring psychiatric symptoms and functional outcomes for adults with Tourette's disorder (TD). This information is essential for effective treatment planning. This study examined the effects of behavior therapy on psychiatric symptoms and functional outcomes in older adolescents and adults with TD.
A total of 122 individuals with TD or a chronic tic disorder participated in a clinical trial comparing behavior therapy to psychoeducation and supportive therapy. At baseline, posttreatment, and follow-up visits, participants completed assessments of tic severity, co-occurring symptoms (inattention, impulsiveness, hyperactivity, anger, anxiety, depression, obsessions, and compulsions), and psychosocial functioning. We compared changes in tic severity, psychiatric symptoms, and functional outcomes using repeated measure and one-way analysis of variance.
At posttreatment, participants receiving behavior therapy reported greater reductions in obsessions compared to participants in supportive therapy (
$\eta _p^2 $
= 0.04, p = 0.04). Across treatments, a positive treatment response on the Clinical Global Impression of Improvement scale was associated with a reduced disruption in family life (
$\eta _p^2 $
= 0.05, p = 0.02) and improved functioning in a parental role (
$\eta _p^2 $
= 0.37, p = 0.02). Participants who responded positively to eight sessions of behavior therapy had an improvement in tic severity (
$\eta _p^2 $
= 0.75, p < 0.001), inattention (
$\eta _p^2 $
= 0.48, p < 0.02), and functioning (
$\eta _p^2 $
= 0.39–0.42, p < 0.03–0.04) at the 6-month follow-up.
Behavior therapy has a therapeutic benefit for co-occurring obsessive symptoms in the short-term, and reduces tic severity and disability in adults with TD over time. Additional treatments may be necessary to address co-occurring symptoms and improve functional outcomes.
Constitutional scholars emphasize the importance of an enduring, stable constitutional order, which North and Weingast (1989) argue is consistent with credible commitments to sustainable fiscal policies. However, this view is controversial and has received little empirical study. We use 19th-century US state-level data to estimate relationships between constitutional design and the likelihood of a government default. Results indicate that more entrenched and less specific constitutions are associated with a lower likelihood of default.
Building on prior work using Tom Dishion's Family Check-Up, the current article examined intervention effects on dysregulated irritability in early childhood. Dysregulated irritability, defined as reactive and intense response to frustration, and prolonged angry mood, is an ideal marker of neurodevelopmental vulnerability to later psychopathology because it is a transdiagnostic indicator of decrements in self-regulation that are measurable in the first years of life that have lifelong implications for health and disease. This study is perhaps the first randomized trial to examine the direct effects of an evidence- and family-based intervention, the Family Check-Up (FCU), on irritability in early childhood and the effects of reductions in irritability on later risk of child internalizing and externalizing symptomatology. Data from the geographically and sociodemographically diverse multisite Early Steps randomized prevention trial were used. Path modeling revealed intervention effects on irritability at age 4, which predicted lower externalizing and internalizing symptoms at age 10.5. Results indicate that family-based programs initiated in early childhood can reduce early childhood irritability and later risk for psychopathology. This holds promise for earlier identification and prevention approaches that target transdiagnostic pathways. Implications for future basic and prevention research are discussed.