Human factors systems approaches are critical for improving healthcare quality and patient safety. The SEIPS (Systems Engineering Initiative for Patient Safety) model of work system and patient ...safety is a human factors systems approach that has been successfully applied in healthcare research and practice. Several research and practical applications of the SEIPS model are described. Important implications of the SEIPS model for healthcare system and process redesign are highlighted. Principles for redesigning healthcare systems using the SEIPS model are described. Balancing the work system and encouraging the active and adaptive role of workers are key principles for improving healthcare quality and patient safety.
•The SEIPS model of work system and patient safety is a useful systems approach to healthcare quality and patient safety.•The SEIPS model can be used for research and improvement activities for improving healthcare quality and patient safety.•Balancing the work system is a key principle to improve healthcare quality and patient safety.
Abstract
In Bacteria, nucleoid structuring proteins govern nucleoid dynamics and regulate transcription. In Shigella spp., at ≤30°C, the histone-like nucleoid structuring protein (H-NS) ...transcriptionally silences many genes on the large virulence plasmid. Upon a switch to 37°C, VirB, a DNA binding protein and key transcriptional regulator of Shigella virulence, is produced. VirB functions to counter H-NS-mediated silencing in a process called transcriptional anti-silencing. Here, we show that VirB mediates a loss of negative DNA supercoils from our plasmid-borne, VirB-regulated PicsP-lacZ reporter in vivo. The changes are not caused by a VirB-dependent increase in transcription, nor do they require the presence of H-NS. Instead, the VirB-dependent change in DNA supercoiling requires the interaction of VirB with its DNA binding site, a critical first step in VirB-dependent gene regulation. Using two complementary approaches, we show that VirB:DNA interactions in vitro introduce positive supercoils in plasmid DNA. Subsequently, by exploiting transcription-coupled DNA supercoiling, we reveal that a localized loss of negative supercoils is sufficient to alleviate H-NS-mediated transcriptional silencing independently of VirB. Together, our findings provide novel insight into VirB, a central regulator of Shigella virulence and, more broadly, a molecular mechanism that offsets H-NS-dependent silencing of transcription in bacteria.
Cobalt-ferrite (CoFe2O4) based materials are suitable candidates for magnetomechanical sensor applications owing to a strong sensitivity of their magnetostriction to an applied magnetic field. ...Zn-doped cobalt-ferrites, with nominal compositions CoFe2−xZnxO4 (x=0–0.3), were synthesized by auto-combustion technique using Co- , Fe- , and Zn-nitrate as precursors. X-ray spectra analysis and Transmission electron microscopy studies revealed that the as-prepared powders were comprised of nano-crystalline (∼25–30nm) cubic-spinel phase with irregularly-shaped grains morphology along with minor impurity phases. Calcination (800°C for 3h) of the precursor followed by sintering (1300°C for 12h) resulted in a single phase cubic-spinel structure with average grain size ∼2–4 μm, as revealed from scanning electron micrographs. The magnitude of coercive field decreases from ∼540Oe for x=0 to 105Oe for x=0.30. Saturation magnetization initially increases and peaks to ∼87emu/g for x=0.2 and then decreases. The peak value of magnetostriction monotonically decreases with increasing Zn content in the range 0.0–0.3; however the piezomagnetic coefficient (dλ/dH) reaches a maximum value of 105×10−9Oe−1 for x=0.1. The observed variation in piezomagnetic coefficient in the Zn substituted cobalt ferrite is related to the reduced anisotropy of the system. The Zn-doped cobalt-ferrite (x=0.1) having high strain derivative could be a potential material for stress sensor application.
► The magnetoelastic properties of Zn substituted Co-ferrites (CoFe2−xZnxO4) reported. ► The coercive field decreases from ∼540Oe (x=0) to 105Oe (x=0.3). ► Saturation magnetization increases, peaks to 87emu/g (x=0.2), and then decreases. ► The peak value of magnetostriction decreases with increasing Zn content. ► The piezomagnetic coefficient reaches a maximum value 105×10−9Oe−1 for x=0.1.
•Elephants spent less time and were more variable in expressing tactile contact than proximity.•Keepers had excellent levels of agreement in rating elephant bond strength.•More time and consistency ...in proximity by elephants predicted “strong or strongest bond” ratings by keepers.
Understanding the affiliative social relationships, or bonds, between zoo elephants has implications for both their welfare and management, yet there is limited work assessing and describing these bonds. Consequently, there is a need for the development of a reliable assessment tool. We used multiple metrics of proximity and tactile contact, as well as keeper surveys, to assess the social bond strength of 41 elephant dyads from 22 different zoos. Survey descriptions of social bond strength were based on previous research and included proximity and separation-reunion behaviors between individuals in a dyad. Approximately half of the elephant dyads in our study were rated as having a “strong” or “strongest” bond by keepers, who showed excellent agreement in their ratings of elephant bond strength (ICC(1,k)=0.82). Elephant dyads that spent more time in proximity (within two elephant body lengths), and those that were more consistent in this behavior across time had an increased predicted probability of being rated as having a “strong or strongest bond” by keepers (p<0.001; p=0.002; respectively). Affiliative tactile contact within dyads, described using duration, diversity, symmetry, and variability metrics, was not significantly related to keeper assessments of dyad bond strength. On average, proximity within dyads occurred more often and was less variable than dyads’ tactile behaviors. Our results suggest that tactile contact may play a more limited role in the maintenance of zoo elephant social bonds than proximity; however, additional research is needed to confirm this. Additionally, this study suggests that keepers are accurately assessing the proximity behavior of their elephants, highlighting the potential of this survey tool to reliably measure the social bond strength of zoo elephant dyads.
Economic policy decisions often involve a trade-off between equality and efficiency implemented through income redistribution. We test whether people are less likely to purchase equality with their ...own money versus transferring someone else’s money to a low-income group member which reduces inequality at the cost of group efficiency. We synthesize Andreoni and Miller (2002) and Engelmann and Strobel (2004) by using an experiment that allows us to measure willingness-to-pay for equality both with own income and other people’s money. Subjects are more likely to purchase equality with others’ money at the cost of group efficiency. The average individual prefers an outcome with more own income and more inequality. Willingness-to-pay for equality is greater than zero when using others’ money, while subjects are sensitive to prices even when making purchases with others’ money. When the cost in terms of group efficiency is very high, subjects usually do not choose to reduce inequality. We find the same outcome for majority-rule decisions and when subjects decide as a dictator.
•Most people do not purchase equality with their own money.•Individuals purchase more equality with other people’s money.•People purchase less equality with their money when the price increases.•People purchase less equality with other’s money when the price increases.•Individuals make similar decisions in dictatorial and voting environments.
species, the causal agents of bacillary dysentery, use a type III secretion system (T3SS) to inject two waves of virulence proteins, known as effectors, into the colonic epithelium to subvert host ...cell machinery. Prior to host cell contact and secretion of the first wave of T3SS effectors, OspD1, an effector and antiactivator protein, prevents premature production of the second wave of effectors. Despite this important role, regulation of the
gene is not well understood. While
belongs to the large regulon of VirB, a transcriptional antisilencing protein that counters silencing mediated by the histone-like nucleoid structuring protein H-NS, it remains unclear if VirB directly or indirectly regulates
Additionally, it is not known if
is regulated by H-NS. Here, we identify the primary
transcription start site (+1) and show that the
promoter is remotely regulated by both VirB and H-NS. Our findings demonstrate that VirB regulation of
requires at least one of the two newly identified VirB regulatory sites, centered at -978 and -1270 relative to the
+1. Intriguingly, one of these sites lies on a 193-bp sequence found in three conserved locations on the large virulence plasmids of
The region required for H-NS-dependent silencing of
lies between -1120 and -820 relative to the
+1. Thus, our study provides further evidence that
-acting regulatory sequences for transcriptional antisilencers and silencers, such as VirB and H-NS, can lie far upstream of the canonical bacterial promoter region (i.e., -250 to +1).
Transcriptional silencing and antisilencing mechanisms regulate virulence gene expression in many important bacterial pathogens. In
species, plasmid-borne virulence genes, such as those encoding the type III secretion system (T3SS), are silenced by the histone-like nucleoid structuring protein H-NS and antisilenced by VirB. Previous work at the plasmid-borne
locus revealed that VirB binds to a remotely located
-acting regulatory site to relieve transcriptional silencing mediated by H-NS. Here, we characterize a second example of remote VirB antisilencing at
, which encodes a T3SS antiactivator and effector. Our study highlights that remote transcriptional silencing and antisilencing occur more frequently in
than previously thought, and it raises the possibility that long-range transcriptional regulation in bacteria is commonplace.
Stereotypic behavior is an important indicator of compromised welfare. Zoo elephants are documented to perform stereotypic behavior, but the factors that contribute to performance have not been ...systematically assessed. We collected behavioral data on 89 elephants (47 African Loxodonta africana, 42 Asian Elephas maximus) at 39 North American zoos during the summer and winter. Elephants were videoed for a median of 12 daytime hours per season. A subset of 32 elephants (19 African, 13 Asian) was also observed live for a median of 10.5 nighttime hours. Percentages of visible behavior scans were calculated from five minute instantaneous samples. Stereotypic behavior was the second most commonly performed behavior (after feeding), making up 15.5% of observations during the daytime and 24.8% at nighttime. Negative binomial regression models fitted with generalized estimating equations were used to determine which social, housing, management, life history, and demographic variables were associated with daytime and nighttime stereotypic behavior rates. Species was a significant risk factor in both models, with Asian elephants at greater risk (daytime: p<0.001, Risk Ratio = 4.087; nighttime: p<0.001, Risk Ratio = 8.015). For both species, spending time housed separately (p<0.001, Risk Ratio = 1.009), and having experienced inter-zoo transfers (p<0.001, Risk Ratio = 1.175), increased the risk of performing higher rates of stereotypy during the day, while spending more time with juvenile elephants (p<0.001, Risk Ratio = 0.985), and engaging with zoo staff reduced this risk (p = 0.018, Risk Ratio = 0.988). At night, spending more time in environments with both indoor and outdoor areas (p = 0.013, Risk Ratio = 0.987) and in larger social groups (p = 0.039, Risk Ratio = 0.752) corresponded with reduced risk of performing higher rates of stereotypy, while having experienced inter-zoo transfers (p = 0.033, Risk Ratio = 1.115) increased this risk. Overall, our results indicate that factors related to the social environment are most influential in predicting elephant stereotypic behavior rates.
We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target ...reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.
Tridymite, a low-pressure, high-temperature (>870 °C) SiO₂ polymorph, was detected in a drill sample of laminated mudstone (Buckskin) at Marias Pass in Gale crater, Mars, by the Chemistry and ...Mineralogy X-ray diffraction instrument onboard the Mars Science Laboratory rover Curiosity. The tridymitic mudstone has ∼40 wt.% crystalline and ∼60 wt.% X-ray amorphous material and a bulk composition with ∼74 wt.% SiO₂ (Alpha Particle X-Ray Spectrometer analysis). Plagioclase (∼17 wt.% of bulk sample), tridymite (∼14 wt.%), sanidine (∼3 wt.%), cation-deficient magnetite (∼3 wt.%), cristobalite (∼2 wt.%), and anhydrite (∼1 wt.%) are the mudstone crystalline minerals. Amorphous material is silica-rich (∼39 wt.% opal-A and/or high-SiO₂ glass and opal-CT), volatile-bearing (16 wt.% mixed cation sulfates, phosphates, and chlorides–perchlorates–chlorates), and has minor TiO₂ and Fe₂O₃T oxides (∼5 wt.%). Rietveld refinement yielded a monoclinic structural model for a well-crystalline tridymite, consistent with high formation temperatures. Terrestrial tridymite is commonly associated with silicic volcanism, and detritus from such volcanism in a “Lake Gale” catchment environment can account for Buckskin’s tridymite, cristobalite, feldspar, and any residual high-SiO₂ glass. These cogenetic detrital phases are possibly sourced from the Gale crater wall/rim/central peak. Opaline silica could form during diagenesis from high-SiO₂ glass, as amorphous precipitated silica, or as a residue of acidic leaching in the sediment source region or at Marias Pass. The amorphous mixed-cation salts and oxides and possibly the crystalline magnetite (otherwise detrital) are primary precipitates and/or their diagenesis products derived from multiple infiltrations of aqueous solutions having variable compositions, temperatures, and acidities. Anhydrite is post lithification fracture/vein fill.
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