4,837 research outputs found
Coexistence between fluid and crystalline phases of proteins in photosynthetic membranes
Photosystem II (PSII) and its associated light-harvesting complex II (LHCII)
are highly concentrated in the stacked grana regions of photosynthetic
thylakoid membranes. Within the membrane, PSII-LHCII supercomplexes can be
arranged in disordered packings, ordered arrays, or mixtures thereof. The
physical driving forces underlying array formation are unknown, complicating
attempts to determine a possible functional role for arrays in regulating light
harvesting or energy conversion efficiency. Here we introduce a coarse-grained
model of protein interactions in coupled photosynthetic membranes, focusing on
just two particle types that feature simple shapes and potential energies
motivated by structural studies. Reporting on computer simulations of the
model's equilibrium fluctuations, we demonstrate its success in reproducing
diverse structural features observed in experiments, including extended
PSII-LHCII arrays. Free energy calculations reveal that the appearance of
arrays marks a phase transition from the disordered fluid state to a
system-spanning crystal, which can easily be arrested by thermodynamic
constraints or slow dynamics. The region of fluid-crystal coexistence is broad,
encompassing much of the physiologically relevant parameter regime. Our results
suggest that grana membranes lie at or near phase coexistence, conferring
significant structural and functional flexibility to this densely packed
membrane protein system.Comment: 11 pages, 5 figure
A Unique Approach to Combating Zebra Mussels
Zebra mussels are an invasive species seen in many countries worldwide. Zebra mussels not only cause a threat to the surrounding wildlife by out-competing other filter feeders resulting in the starvation of native species, but they also impact human activity. To prevent the dangerous effects of zebra mussels, research was done to better understand the properties and structures of their composition and metabolites. With this research being investigative the hypothesis is that by using organic chemistry methods, different components in Zebra mussels will be able to be detected. In addition, the physical structure of the Zebra mussel that is hypothesized to contain a larger variety of metabolites is the innards because they are the structure being protected by the outer shell. Methods used to further separate the compounds and collect data during this experiment include the use of bioassay and structural guided fractionation such as TLC, HPLC, IR, 13C NMR, 1H NMR, filtration, and separation. TLC was used primarily to analyze which samples contained the most components. HPLC was used to separate the components even further by placing the extracts from specific peaks into beakers. IR and NMR were analyzed to look for functional groups. Results, thus far, concluded that the Zebra mussel shells contained more metabolites than the guts and an expected metabolite is to have a structure with four protons attached to a benzene ring. This was determined through TLC separations. Further conclusions are currently under investigation. Additionally, an investigation into the components of Zebra mussels could lead to identifying secondary metabolites such as the polyketide pathway which could play a significant role in their survival
Emergency departments as complex adaptive systems
Introduction
Globally, emergency departments (ED) are confronted with yearly rises in visit numbers and an increasingly older and multimorbid patient population. Several work system factors were associated with employee well-being and patient safety in previous literature. This thesis reports results of a mixed-methods intervention study investigating interrelationships between psychosocial ED work system factors, employee well-being and quality of patient care under consideration of the concept of resilient health care and complex adaptive systems (CAS).
Methods
A before and after study including an interrupted time-series (ITS) design was established in the multidisciplinary ED of a tertiary referral hospital in Southern Germany between 2015 and 2017. Applied methods and data sources included (1) standardized employee surveys, (2) structured work observations, (3) patient surveys, (4) register data, and (5) qualitative interviews. Additional data on employees’ activity and interruption patterns was collected in one US-American ED in 2016.
Results
Assessment of psychosocial work factors indicated considerable work demands for ED employees before and after the participative intervention comprising ten health circles. Inconsistent longitudinal intervention effects were found for changes in psychosocial work factors and employee mental wellbeing, e.g., increase in job control but decline in job satisfaction. Improvements in patient satisfaction were observed over time. Interviews revealed facilitators (e.g., comprehensive approach, employee participation) and barriers (e.g., understaffing, organizational constraints) for intervention implementation. Further associations between work interruptions and ED patient satisfaction as well as cross-national differences in ED work activity patterns were observed.
Conclusions
Reasons for inconsistent intervention results stem from the complexity of the ED work system including profession- and institution-specific challenges and individual stress experiences of employees. Studies should further consider employee health as a concurrent determinant as well as outcome in the theoretical concepts of CAS and resilient health care.Einleitung
Notaufnahmen (NA) sind mit jährlich steigenden Besuchszahlen und einer älter werdenden und multimorbiden Patientenpopulation konfrontiert. Psychosoziale Arbeitsbedingungen wurden in der Literatur mit der Gesundheit von Beschäftigten und der Qualität der Versorgung assoziiert. Diese Dissertation berichtet die Ergebnisse einer Mixed-Methods-Interventionsstudie, die diese Zusammenhänge unter Berücksichtigung der Theorie komplexer adaptiver Systeme adressiert.
Methode
In der interdisziplinären NA eines süddeutschen Maximalversorgers wurde zwischen 2015 und 2017 eine Vorher-Nachher-Studie mit einem sog. Interrupted Time-Series Design durchgeführt. Methoden und Datenquellen umfassten (1) standardisierte Mitarbeiterbefragungen, (2) strukturierte Arbeitsbeobachtungen, (3) Patientenbefragungen, (4) Sekundärdaten und (5) qualitative Interviews. Ergänzende Daten zu Arbeitsbedingungen wurden 2016 in einer US-amerikanischen NA erhoben.
Ergebnisse
Vor und nach der partizipativen Intervention – bestehend aus 10 Gesundheitszirkeln – wurden erhebliche psychosoziale Arbeitsbelastungen für in der NA Beschäftigte identifiziert. Inkonsistente Längsschnitteffekte zeigten Veränderungen in psychosozialen Arbeitsbedingungen und im psychischen Wohlbefinden, z.B. Zunahme der Autonomie jedoch verringerte Arbeitszufriedenheit. Die Patientenzufriedenheit verbesserte sich im Laufe der Zeit. Unterstützende Faktoren für die Implementierung der Intervention waren ihr umfassender Ansatz und die Mitarbeiterbeteiligung wohingegen personelle Unterbesetzung und organisatorische Einschränkungen Barrieren darstellten. Weitere Zusammenhänge zwischen Arbeitsunterbrechungen und der Patientenzufriedenheit sowie länderübergreifende Unterschiede in NA-Arbeitsabläufen wurden beobachtet.
Schlussfolgerungen
Gründe für inkonsistente Interventionsergebnisse liegen in der Komplexität des NA-Arbeitssystems einschließlich berufs- und institutionsspezifischer Herausforderungen und individueller Beanspruchungserfahrungen der Beschäftigten begründet, welche in zukünftigen Studien zur arbeitsbezogenen Gesundheit im Rahmen der CAS-Theorie berücksichtigt werden sollten
Evaluation Of Movements And Habitat Use Of Suburban Striped Skunks (Mephitis Mephitis) In The Northern Great Plains To Inform Rabies Management
Few studies have investigated the ecology of urban striped skunks (Mephitis mephitis) despite their role as a primary rabies vector species paired with an ability to thrive in these landscapes. Our aim was to obtain baseline ecological information with an emphasis on spatial ecology of urban striped skunks in the Northern Great Plains region that is missing in the literature. This information, such as home range, nightly movements, habitat selection, and denning behavior is important for informing rabies management decisions such as the placement of oral rabies vaccine (ORV) baits. We used radio telemetry equipment to track 22 (4M, 18 F) skunks from September 2016âNovember 2016 and March 2017âNovember 2017 and monitored denning sites with trail cameras October 2016âJuly 2017. Size of home ranges estimated using kernel density estimation and least squares cross validation determined males (x Ì = 4.36 km2, SE ± 0.79) had larger home ranges than females (x Ì = 1.79 km2, SE ± 0.24). Female skunk home ranges differed by season with the largest home ranges found in summer 2017. However, rate of nightly movements (m/hr) among female skunks did not differ within seasons (x Ì = 184.79 m/hr, SE ± 0.53). Moreover, we found no evidence that use-availability was associated with habitat type among female skunks. The strongest predictor of habitat use was distance to water sources with female skunks more likely to be found closer to this habitat type; however, we found no association of use with road factors and geographic location within the city. We observed communal denning in 3 winter den sites, which could amplify rabies transmission during these periods of inactivity. Targeting ORV efforts in areas near water and den sites may be warranted, but considering differences in urban skunk habitat selection studies, we caution that ORV baiting programs may not be one-size-fits-all, and a framework for effective bait placement would be most successful should similar studies be conducted beforehand
Emergency departments as complex adaptive systems
Introduction
Globally, emergency departments (ED) are confronted with yearly rises in visit numbers and an increasingly older and multimorbid patient population. Several work system factors were associated with employee well-being and patient safety in previous literature. This thesis reports results of a mixed-methods intervention study investigating interrelationships between psychosocial ED work system factors, employee well-being and quality of patient care under consideration of the concept of resilient health care and complex adaptive systems (CAS).
Methods
A before and after study including an interrupted time-series (ITS) design was established in the multidisciplinary ED of a tertiary referral hospital in Southern Germany between 2015 and 2017. Applied methods and data sources included (1) standardized employee surveys, (2) structured work observations, (3) patient surveys, (4) register data, and (5) qualitative interviews. Additional data on employees’ activity and interruption patterns was collected in one US-American ED in 2016.
Results
Assessment of psychosocial work factors indicated considerable work demands for ED employees before and after the participative intervention comprising ten health circles. Inconsistent longitudinal intervention effects were found for changes in psychosocial work factors and employee mental wellbeing, e.g., increase in job control but decline in job satisfaction. Improvements in patient satisfaction were observed over time. Interviews revealed facilitators (e.g., comprehensive approach, employee participation) and barriers (e.g., understaffing, organizational constraints) for intervention implementation. Further associations between work interruptions and ED patient satisfaction as well as cross-national differences in ED work activity patterns were observed.
Conclusions
Reasons for inconsistent intervention results stem from the complexity of the ED work system including profession- and institution-specific challenges and individual stress experiences of employees. Studies should further consider employee health as a concurrent determinant as well as outcome in the theoretical concepts of CAS and resilient health care.Einleitung
Notaufnahmen (NA) sind mit jährlich steigenden Besuchszahlen und einer älter werdenden und multimorbiden Patientenpopulation konfrontiert. Psychosoziale Arbeitsbedingungen wurden in der Literatur mit der Gesundheit von Beschäftigten und der Qualität der Versorgung assoziiert. Diese Dissertation berichtet die Ergebnisse einer Mixed-Methods-Interventionsstudie, die diese Zusammenhänge unter Berücksichtigung der Theorie komplexer adaptiver Systeme adressiert.
Methode
In der interdisziplinären NA eines süddeutschen Maximalversorgers wurde zwischen 2015 und 2017 eine Vorher-Nachher-Studie mit einem sog. Interrupted Time-Series Design durchgeführt. Methoden und Datenquellen umfassten (1) standardisierte Mitarbeiterbefragungen, (2) strukturierte Arbeitsbeobachtungen, (3) Patientenbefragungen, (4) Sekundärdaten und (5) qualitative Interviews. Ergänzende Daten zu Arbeitsbedingungen wurden 2016 in einer US-amerikanischen NA erhoben.
Ergebnisse
Vor und nach der partizipativen Intervention – bestehend aus 10 Gesundheitszirkeln – wurden erhebliche psychosoziale Arbeitsbelastungen für in der NA Beschäftigte identifiziert. Inkonsistente Längsschnitteffekte zeigten Veränderungen in psychosozialen Arbeitsbedingungen und im psychischen Wohlbefinden, z.B. Zunahme der Autonomie jedoch verringerte Arbeitszufriedenheit. Die Patientenzufriedenheit verbesserte sich im Laufe der Zeit. Unterstützende Faktoren für die Implementierung der Intervention waren ihr umfassender Ansatz und die Mitarbeiterbeteiligung wohingegen personelle Unterbesetzung und organisatorische Einschränkungen Barrieren darstellten. Weitere Zusammenhänge zwischen Arbeitsunterbrechungen und der Patientenzufriedenheit sowie länderübergreifende Unterschiede in NA-Arbeitsabläufen wurden beobachtet.
Schlussfolgerungen
Gründe für inkonsistente Interventionsergebnisse liegen in der Komplexität des NA-Arbeitssystems einschließlich berufs- und institutionsspezifischer Herausforderungen und individueller Beanspruchungserfahrungen der Beschäftigten begründet, welche in zukünftigen Studien zur arbeitsbezogenen Gesundheit im Rahmen der CAS-Theorie berücksichtigt werden sollten
The use of the Socratic method in a contemporary high school classroom in developing problem-solving, critical thinking, and decision making skills
The purpose of this action research was to attempt to use a modified approach to the Socratic method in a contemporary high school classroom as a means of developing problem-solving, critical thinking, and decision-making skills in high school students. The participants in the study were 16 male students and 13 female students from two sections of an eleventh grade Honors English class at a suburban high school in southern New Jersey. These students were selected as a population of convenience during the researcher\u27s Clinical Internship II experience. As a part of regular classroom instruction, the researcher employed a modified form of the Socratic method, using journal prompts and a subsequent discussion model. Student responses to these prompts were collected and analyzed. Classroom use of the method and some implications of gender are discussed
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