999 research outputs found
Impact of management attitudes on perceived thermal comfort
Objectives This study examined the influence of some organizational and management characteristics on the perception of indoor environment qualities such as thermal comfort and related stress. Methods One open office in each of three organizations in Eindhoven was studied. An office environment survey, a questionnaire on extended cognitive failure, and a questionnaire on effort-reward imbalance were combined to assess the perceived management attitudes and perceived (dis)comfort of 50 workers in each of two of the offices and of 43 persons in the third. The study included data on perceived and measured thermal comfort and indoor-air quality, self-reported personal factors, and organizational factors (N=46). Results Perceived thermal comfort correlated with perceived symptoms of the sick building syndrome; it also correlated or was associated with the following three management-related parameters: (i) employees' stress, (ii) employees' overcommitment to work, and (iii) employees' perceived privacy. Conclusions The managerial characteristics of an organization influences thermal comfort as perceived by employees
Flexibility properties in Complex Analysis and Affine Algebraic Geometry
In the last decades affine algebraic varieties and Stein manifolds with big
(infinite-dimensional) automorphism groups have been intensively studied.
Several notions expressing that the automorphisms group is big have been
proposed. All of them imply that the manifold in question is an
Oka-Forstneri\v{c} manifold. This important notion has also recently merged
from the intensive studies around the homotopy principle in Complex Analysis.
This homotopy principle, which goes back to the 1930's, has had an enormous
impact on the development of the area of Several Complex Variables and the
number of its applications is constantly growing. In this overview article we
present 3 classes of properties: 1. density property, 2. flexibility 3.
Oka-Forstneri\v{c}. For each class we give the relevant definitions, its most
significant features and explain the known implications between all these
properties. Many difficult mathematical problems could be solved by applying
the developed theory, we indicate some of the most spectacular ones.Comment: thanks added, minor correction
On the generalized Davenport constant and the Noether number
Known results on the generalized Davenport constant related to zero-sum
sequences over a finite abelian group are extended to the generalized Noether
number related to the rings of polynomial invariants of an arbitrary finite
group. An improved general upper bound is given on the degrees of polynomial
invariants of a non-cyclic finite group which cut out the zero vector.Comment: 14 page
Electrokinetic properties of NaCl solution via molecular dynamics simulations with scaled-charge electrolytes
ACKNOWLEDGMENTS The authors thank Mrs. Flavia Silva de Castro, from the British Consulate-General in Rio de Janeiro, for her effort in promoting a closer interaction between British and Brazilian universities. This work has been supported by the São Paulo Research Foundation (FAPESP) for the project funding (Grant Nos. 2018/02713-8, 2020/13300-6, and 2021/13068-9), the “Centro Nacional de Processamento de Alto Desempenho em São Paulo” (CENAPAD-SP), and the John David Rogers Computing Center (CCJDR) at the Institute of Physics “Gleb Wataghin” of the University of Campinas for providing computational resources.Peer reviewe
Persistent Homology Over Directed Acyclic Graphs
We define persistent homology groups over any set of spaces which have
inclusions defined so that the corresponding directed graph between the spaces
is acyclic, as well as along any subgraph of this directed graph. This method
simultaneously generalizes standard persistent homology, zigzag persistence and
multidimensional persistence to arbitrary directed acyclic graphs, and it also
allows the study of more general families of topological spaces or point-cloud
data. We give an algorithm to compute the persistent homology groups
simultaneously for all subgraphs which contain a single source and a single
sink in arithmetic operations, where is the number of vertices in
the graph. We then demonstrate as an application of these tools a method to
overlay two distinct filtrations of the same underlying space, which allows us
to detect the most significant barcodes using considerably fewer points than
standard persistence.Comment: Revised versio
Reducing preventable adverse events in obstetrics by improving interprofessional communication skills - Results of an intervention study.
BACKGROUND: Progress in medicine involves the structured analysis and communication of errors. Comparability between the individual disciplines is only possible to a limited extent and obstetrics plays a special role: the expectation of a self-determined and joyful event meets with possibly serious complications in highly complex care situations. This must be managed by an interdisciplinary team with an increasingly condensed workload. Adverse events cannot be completely controlled. However, taking controllable risk factors into account and with a focused communication a reduction of preventable adverse events is possible. In the present study, the effect of interprofessional team training on preventable adverse events in an obstetric department was investigated. METHODS: The training consisted of a 4-h interdisciplinary training session based on psychological theories. Preventable adverse events were defined in six categories according to potential patterns of causation. 2,865 case records of a refence year (2018) and 2,846 case records of the year after the intervention (2020) were retrospectively evaluated. To determine the communication training effect, the identified preventable adverse events of 2018 and 2020 were compared according to categories and analyzed for obstetrically relevant controllable and uncontrollable risk factors. Questionnaires were used to identify improvements in self-reported perceptions and behaviors. RESULTS: The results show that preventable adverse events in obstetrics were significantly reduced after the intervention compared to the reference year before the intervention (13.35% in the year 2018 vs. 8.83% in 2020, p < 0.005). Moreover, obstetrically controllable risk factors show a significant reduction in the year after the communication training. The questionnaires revealed an increase in perceived patient safety (t(28) = 4.09, p < .001), perceived communication behavior (t(30) = -2.95, p = .006), and self-efficacy to cope with difficult situations (t(28) = -2.64, p = .013). CONCLUSIONS: This study shows that the communication training was able to reduce preventable adverse events and thus increase patient safety. In the future, regular trainings should be implemented alongside medical emergency trainings in obstetrics to improve patient safety. Additionally, this leads to the strengthening of human factors and ultimately also to the prevention of second victims. Further research should follow up implementing active control groups and a randomized-controlled trail study design. TRIAL REGISTRATION: The study was approved by the Ethics Committee of University Hospital (protocol code 114/19-FSt/Sta, date of approval 29 May 2019), study registration: NCT03855735
Compaction and dilation rate dependence of stresses in gas-fluidized beds
A particle dynamics-based hybrid model, consisting of monodisperse spherical
solid particles and volume-averaged gas hydrodynamics, is used to study
traveling planar waves (one-dimensional traveling waves) of voids formed in
gas-fluidized beds of narrow cross sectional areas. Through ensemble-averaging
in a co-traveling frame, we compute solid phase continuum variables (local
volume fraction, average velocity, stress tensor, and granular temperature)
across the waves, and examine the relations among them. We probe the
consistency between such computationally obtained relations and constitutive
models in the kinetic theory for granular materials which are widely used in
the two-fluid modeling approach to fluidized beds. We demonstrate that solid
phase continuum variables exhibit appreciable ``path dependence'', which is not
captured by the commonly used kinetic theory-based models. We show that this
path dependence is associated with the large rates of dilation and compaction
that occur in the wave. We also examine the relations among solid phase
continuum variables in beds of cohesive particles, which yield the same path
dependence. Our results both for beds of cohesive and non-cohesive particles
suggest that path-dependent constitutive models need to be developed.Comment: accepted for publication in Physics of Fluids (Burnett-order effect
analysis added
Categorification of skew-symmetrizable cluster algebras
We propose a new framework for categorifying skew-symmetrizable cluster
algebras. Starting from an exact stably 2-Calabi-Yau category C endowed with
the action of a finite group G, we construct a G-equivariant mutation on the
set of maximal rigid G-invariant objects of C. Using an appropriate cluster
character, we can then attach to these data an explicit skew-symmetrizable
cluster algebra. As an application we prove the linear independence of the
cluster monomials in this setting. Finally, we illustrate our construction with
examples associated with partial flag varieties and unipotent subgroups of
Kac-Moody groups, generalizing to the non simply-laced case several results of
Gei\ss-Leclerc-Schr\"oer.Comment: 64 page
Barriers and Facilitators of Safe Communication in Obstetrics: Results from Qualitative Interviews with Physicians, Midwives and Nurses.
Patient safety is an important objective in health care. Preventable adverse events (pAEs) as the counterpart to patient safety are harmful incidents that fell behind health care standards and have led to temporary or permanent harm or death. As safe communication and mutual understanding are of crucial importance for providing a high quality of care under everyday conditions, we aimed to identify barriers and facilitators that impact safe communication in obstetrics from the subjective perspective of health care workers. A qualitative study with 20 semi-structured interviews at two university hospitals in Germany was conducted to explore everyday perceptions from a subjective perspective (subjective theories). Physicians, midwives, and nurses in a wide span of professional experience and positions were enrolled. We identified a structural area of conflict at the professional interface between midwives and physicians. Mandatory interprofessional meetings, acceptance of subjective mistakes, mutual understanding, and debriefings of conflict situations are reported to improve collaboration. Additionally, emergency trainings, trainings in precise communication, and handovers are proposed to reduce risks for pAEs. Furthermore, the participants reported time-constraints and understaffing as a huge burden that hinders safe communication. Concluding, safety culture and organizational management are closely entwined and strategies should address various levels of which communication trainings are promising
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