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Until recently, the influence of basal liquid water on the evolution of buried glaciers in Mars' mid latitudes was assumed to be negligible because the latter stages of Mars' Amazonian period (3 Ga to present) have long been thought to have been similarly cold and dry to today. Recent identifications of several landforms interpreted as eskers associated with these young (100s Ma) glaciers calls this assumption into doubt. They indicate basal melting (at least locally and transiently) of their parent glaciers. Although rare, they demonstrate a more complex mid-to-late Amazonian environment than was previously understood. Here, we discuss several open questions posed by the existence of glacier-linked eskers on Mars, including on their global-scale abundance and distribution, the drivers and dynamics of melting and drainage, and the fate of meltwater upon reaching the ice margin. Such questions provide rich opportunities for collaboration between the Mars and Earth cryosphere research communities.
Black women in elective office in the United States have demonstrated how descriptive representative transforms democratic institutions. This transformation is most evident in previously uncrystallized interests, those new to the agenda or not yet owned by specific political groups (Mansbridge 1999), articulated in legislative communication and action. For instance, Black maternal health is an issue that addresses the disproportionately poor health outcomes among Black women, who face systemic barriers to equitable care (Crear-Perry et al. 2021). Congresswoman Lauren Underwood’s (D-IL) 2021 Momnibus legislation included 12 bipartisan bills to address racial and ethnic disparities faced by mothers, children, and individuals who birth. Indeed, the creation of the Black Maternal Health Caucus (BMHC) demonstrates the legislative agency of Black women to form identity- and issue-based coalitions that suit the needs of Black women—needs often overlooked by Black men and white women.
We aimed to identify factors independently associated with the need for inotropic support for low cardiac output or haemodynamic instability after pulmonary artery banding surgery for CHD.
We performed a retrospective chart review of all neonates and infants who underwent pulmonary banding between January 2016 and June 2019 at our institution. Bivariate and multivariable analyses were performed to identify factors independently associated with the use of post-operative inotropic support, defined as the initiation of inotropic infusion(s) for depressed myocardial function, hypotension, or compromised perfusion within 24 hours of pulmonary artery banding.
We reviewed 61 patients. Median age at surgery was 10 days (25%,75%:7,30). Cardiac anatomy was biventricular in 38 patients (62%), hypoplastic right ventricle in 14 patients (23%), and hypoplastic left ventricle in 9 patients (15%). Inotropic support was implemented in 30 patients (49%). Baseline characteristics of patients who received inotropic support, including ventricular anatomy and pre-operative ventricular function, were not statistically different from the rest of the cohort. Patients who received inotropic support, however, were exposed to larger cumulative doses of ketamine intraoperatively – median 4.0 mg/kg (25%,75%:2.8,5.9) versus 1.8 mg/kg (25%,75%:0.9,4.5), p < 0.001. In a multivariable model, cumulative ketamine dose greater than 2.5mg/kg was associated with post-operative inotropic support (odds ratio 5.5; 95% confidence interval: 1.7,17.8), independent of total surgery time.
Inotropic support was administered in approximately half of patients who underwent pulmonary artery banding and more commonly occurred in patients who received higher cumulative doses of ketamine intraoperatively, independent of the duration of surgery.
What are the determinants of ethnic violence? Existing research has forwarded a range of often competing explanations, from political opportunism to economic competition to state incapacity. We argue that this diversity of accounts is attributable, in part, to scholars’ tendency to lump together distinct forms of ethnic violence that have different underlying determinants. We propose that scholars instead disaggregate ethnic violence and put forward a typology based on the target of the attack (properties vs. individuals) and whether assailants use arms. We demonstrate the utility of this typology by applying it to an original dataset of ethnic attacks against Christians in Egypt from 2013 to 2018. In addition to a set of shared factors, we find that unarmed attacks against property (“burnings”) are the product of political mobilization, unarmed attacks against individuals (“beatings”) are related to socioeconomic tensions, and armed attacks (“bombings”) follow the strategic logic of terrorist violence.
Amiodarone may be considered for patients with junctional ectopic tachycardia refractory to treatment with sedation, analgesia, cooling, and electrolyte replacements. There are currently no published pediatric data regarding the hemodynamic effects of the newer amiodarone formulation, PM101, devoid of hypotensive agents used in the original amiodarone formulation. We performed a single-center, retrospective, descriptive study from January 2012 to December 2020 in a pediatric ICU. Thirty-three patients were included (22 male and 11 female) between the ages of 1.1 and 1,460 days who developed post-operative junctional ectopic tachycardia or other tachyarrhythmias requiring PM101. Data analysis was performed on hemodynamic parameters (mean arterial pressures and heart rate) and total PM101 (mg/kg) from hour 0 of amiodarone administration to hour 72. Adverse outcomes were defined as Vasoactive-Inotropic Score >20, patients requiring ECMO or CPR, or patient death. There was no statistically significant decrease in mean arterial pressures within the 6 hours of PM101 administration (p > 0.05), but there was a statistically significant therapeutic decrease in heart rate for resolution of tachyarrhythmia (p < 0.05). Patients received up to 25 mg/kg in an 8-hour time for rate control. Average rate control was achieved within 11.91 hours and average rhythm control within 62 hours. There were four adverse events around the time of PM101 administration, with three determined to not be associated with the medication. PM101 is safe and effective in the pediatric cardiac surgical population. Our study demonstrated that PM101 can be used in a more aggressive dosing regimen than previously reported in pediatric literature with the prior formulation.
Effective incident management is essential for coordinating efforts of multiple disciplines and stakeholders when responding to emergencies, including public health disasters such as the ongoing coronavirus disease 2019 (COVID-19) pandemic.
Existing research frameworks tend to focus on formal structures and doctrine (eg, ICS-NIMS); however, organizational processes that underlie incident management have not been systematically assessed and synthesized into a coherent conceptual framework.
The lack of a framework has hindered the development of measures of performance that could be used to further develop the evidence base and facilitate process improvement. To address this gap, we present a conceptual framework of incident management drawn from expert feedback and a review of literature on incident management and related fields. The framework features 23 measurement constructs grouped into 5 domains: (1) situational awareness and information sharing, (2) incident action and implementation planning, (3) resource management and mobilization, (4) coordination and collaboration, and (5) feedback and continuous quality improvement.
As such, the article provides a first step toward the development of robust measures for assessing the performance and effectiveness of incident management systems.
This study determines which factors are associated with the use of rotational grazing and the frequency with which Tennessee producers rotate cattle during the summer months. Survey data were used to estimate an ordered response model with sample selection. Most respondents used rotational grazing, and the most frequent rotational schedule was rotating cattle one to two times per month. Factors including labor, capital, knowledge, and water availability influenced the use of rotational grazing and the frequency of rotating cattle. The insights from this study can inform the development of incentives to promote more intensive use of rotational grazing.
There are fewer Certified Organic producers in the Mid-South US (southern half of Missouri, western Kentucky and Tennessee, northern Arkansas and eastern Oklahoma) than in other regions of the country such as the Upper Midwest, West Coast, or Northeastern US. Taus et al. (2013) The Professional Geographer 65, 87–102, posit that these clusters suggest regional characteristics impact adoption of organic agriculture and admit that regional studies lack consensus on the role of factors that drive adoption. This paper seeks to understand if there are regionally distinct challenges and opportunities for organic production in the region. Fourteen certified organic producers in Missouri were interviewed and areas of challenges and opportunities specific to their certification were identified within the three a priori themes of (1) biophysical characteristics, (2) marketing infrastructure and (3) financial feasibility. We suggest directions for future policy support from the National Organic Program (NOP) and bolstered feedback structures within the National Organic Standards Board to address regional disparities.
Early in the COVID-19 pandemic, the World Health Organization stressed the importance of daily clinical assessments of infected patients, yet current approaches frequently consider cross-sectional timepoints, cumulative summary measures, or time-to-event analyses. Statistical methods are available that make use of the rich information content of longitudinal assessments. We demonstrate the use of a multistate transition model to assess the dynamic nature of COVID-19-associated critical illness using daily evaluations of COVID-19 patients from 9 academic hospitals. We describe the accessibility and utility of methods that consider the clinical trajectory of critically ill COVID-19 patients.
Patients presenting to hospital with suspected coronavirus disease 2019 (COVID-19), based on clinical symptoms, are routinely placed in a cohort together until polymerase chain reaction (PCR) test results are available. This procedure leads to delays in transfers to definitive areas and high nosocomial transmission rates. FebriDx is a finger-prick point-of-care test (PoCT) that detects an antiviral host response and has a high negative predictive value for COVID-19. We sought to determine the clinical impact of using FebriDx for COVID-19 triage in the emergency department (ED).
We undertook a retrospective observational study evaluating the real-world clinical impact of FebriDx as part of an ED COVID-19 triage algorithm.
Emergency department of a university teaching hospital.
Patients presenting with symptoms suggestive of COVID-19, placed in a cohort in a ‘high-risk’ area, were tested using FebriDx. Patients without a detectable antiviral host response were then moved to a lower-risk area.
Between September 22, 2020, and January 7, 2021, 1,321 patients were tested using FebriDx, and 1,104 (84%) did not have a detectable antiviral host response. Among 1,104 patients, 865 (78%) were moved to a lower-risk area within the ED. The median times spent in a high-risk area were 52 minutes (interquartile range [IQR], 34–92) for FebriDx-negative patients and 203 minutes (IQR, 142–255) for FebriDx-positive patients (difference of −134 minutes; 95% CI, −144 to −122; P < .0001). The negative predictive value of FebriDx for the identification of COVID-19 was 96% (661 of 690; 95% CI, 94%–97%).
FebriDx improved the triage of patients with suspected COVID-19 and reduced the time that severe acute respiratory coronavirus virus 2 (SARS-CoV-2) PCR-negative patients spent in a high-risk area alongside SARS-CoV-2–positive patients.
To contain the spread of COVID-19, experts emphasize the importance of wearing masks. Unfortunately, this practice may put black people at elevated risk for being seen as potential threats by some Americans. In this study, we evaluate whether and how different types of masks affect perceptions of black and white male models. We find that non-black respondents perceive a black male model as more threatening and less trustworthy when he is wearing a bandana or a cloth mask than when he is not wearing his face covering—especially those respondents who score above average in racial resentment, a common measure of racial bias. When he is wearing a surgical mask, however, they do not perceive him as more threatening or less trustworthy. Further, it is not that non-black respondents find bandana and cloth masks problematic in general. In fact, the white model in our study is perceived more positively when he is wearing all types of face coverings. Although mandated mask wearing is an ostensibly race-neutral policy, our findings demonstrate the potential implications are not.
The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.
The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.
MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.
Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.
MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.
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.
In their combination of intensity and geographical extent, the 1848 revolutions were unique – at least in European history. Neither the great French Revolution of 1789, nor the July Revolution of 1830, nor the Paris Commune of 1870, nor the Russian revolutions of 1905 and 1917 sparked a comparable transcontinental cascade. The year 1989 looks like a better comparator, but there is still controversy as to whether these uprisings can be characterized as “revolutions,” and, in any case, their direct impact was limited to the Warsaw Pact states. In 1848, by contrast, parallel political tumults broke out across the entire continent, from Spain and Portugal to Wallachia and Moldavia, from Norway, Denmark, and Sweden to Naples and Palermo. And across the continent, the movements challenging the old regime – radical, democratic, or liberal – developed strikingly similar repertories of claims and objectives. This was the only truly European revolution that there has ever been.
‘If National Socialism had not come into existence’, Joseph Goebbels wrote in July 1942, ‘there is no way [Sepp Dietrich] would have made it further than sergeant. It is our regime that has made him into one of the crucial leaders of troops on the eastern front.’ This undoubtedly accurate observation touches on one of the central questions posed by Sepp Dietrich's journey from petrol station attendant to a senior military command. As a member of Hitler's entourage without any formal officer training whatsoever, Dietrich experienced a meteoric ascent within the Waffen-SS. The propaganda of the regime celebrated him as the embodiment of National Socialist soldierly virtue, establishing him as one of the most popular military commanders of the later war years. This chapter explores a career that was driven by the volatile relationship between personality and political structure.
This chapter is dedicated to my friend and former doctoral supervisor Jonathan Steinberg. Jonathan was a brilliant, charismatic lecturer and a perceptive, generous critic with a sharp eye for the textures of individual personalities, in the past as in the present. Some of the most compelling passages in his first book, Yesterday's Deterrent, a study of Grand Admiral Alfred von Tirpitz, architect of the German pre-war naval programme, were focused on the character and inner life of the protagonist. In All or Nothing, Jonathan's contrastive study of German and Italian policy vis-à-vis the Jews in adjacent occupation zones during the Second World War, the utterances of specific actors were made to carry explanatory weight, a window into the motivational dynamics and attitudes that drove behaviour. He noted that whereas one could find among the Italian sources the voices of officials protesting to their superiors that the Jews in their zone appeared to be ‘decent fellows’ and expressing puzzlement about the German policy of deportation and extermination, no such voices were heard in the German sources. What did that mean? Had these people been educated differently? Was this about divergent features of German and Italian nation building, or did it reflect variant institutional and educational structures? Whatever the answers one found to these questions, the avenue of enquiry began with the behaviour and speech of individual actors. Jonathan often said in conversation: ‘Our work is completely unlike that of the physicists, geologists and molecular biologists, because our subjects talk back at us!’