scholarly journals Transmission dynamics and control of multidrug-resistant Klebsiella pneumoniae in neonates in a developing country

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Thomas Crellen ◽  
Paul Turner ◽  
Sreymom Pol ◽  
Stephen Baker ◽  
To Nguyen Thi Nguyen ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Neonatal Intensive Care ◽  
Dynamic Models ◽  
Generation Cephalosporin ◽  
Multidrug Resistant ◽  
Transmission Risk ◽  
Dynamics And Control ◽  
One Year ◽  
And Control ◽  
The Impact

Multidrug-resistant Klebsiella pneumoniae is an increasing cause of infant mortality in developing countries. We aimed to develop a quantitative understanding of the drivers of this epidemic by estimating the effects of antibiotics on nosocomial transmission risk, comparing competing hypotheses about mechanisms of spread, and quantifying the impact of potential interventions. Using a sequence of dynamic models, we analysed data from a one-year prospective carriage study in a Cambodian neonatal intensive care unit with hyperendemic third-generation cephalosporin-resistant K. pneumoniae. All widely-used antibiotics except imipenem were associated with an increased daily acquisition risk, with an odds ratio for the most common combination (ampicillin + gentamicin) of 1.96 (95% CrI 1.18, 3.36). Models incorporating genomic data found that colonisation pressure was associated with a higher transmission risk, indicated sequence type heterogeneity in transmissibility, and showed that within-ward transmission was insufficient to maintain endemicity. Simulations indicated that increasing the nurse-patient ratio could be an effective intervention.

scholarly journals Impact of Two Antibiotic Therapies on Clinical Outcome and Gut Microbiota Profile in Liver Transplant Paediatric Candidates Colonized by Carbapenem-Resistant Klebsiella pneumoniae CR-KP

2021 ◽  
Vol 11 ◽  
Author(s):  
Sabrina Cardile ◽  
Federica Del Chierico ◽  
Manila Candusso ◽  
Sofia Reddel ◽  
Paola Bernaschi ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Gut Microbiota ◽  
Liver Transplant ◽  
Short Chain Fatty Acids ◽  
Multidrug Resistant ◽  
Transplant Patients ◽  
Carbapenem Resistant ◽  
Serious Infections ◽  
One Year ◽  
The Impact

Colonization by multidrug-resistant (MDR) organisms in liver transplant (LT) candidates significantly affects the LT outcome. To date, consensus about patient management is lacking, including microbiological screening indications. This pilot study aimed to evaluate the impact of carbapenem-resistant Klebsiella pneumoniae (CR-KP) colonization in LT paediatric candidates to enable optimal prevention and therapeutic strategies that exploit both clinical and microbiological approaches. Seven paediatric patients colonized by CR-KP were evaluated before and until one-year post LT. At the time of the transplant, patients were stratified based on antibiotic (ATB) prophylaxis into two groups: ‘standard ATB’ (standard ATB prophylaxis), and ‘targeted ATB’ (MDR antibiogram-based ATB prophylaxis). Twenty-eight faecal samples were collected during follow-up and used for MDR screening and gut microbiota 16S rRNA-based profiling. Post-transplant hospitalization duration was comparable for both groups. With the exception of one patient, no serious infections and/or complications, nor deaths were recorded. A progressive MDR decontamination was registered. In the ‘standard ATB’ group, overall bacterial richness increased. Moreover, 6 months after LT, Lactobacillus and Bulleidia were increased and Enterobacteriaceae and Klebsiella spp. were reduced. In the ‘targeted ATB’ group Klebsiella spp., Ruminococcus gnavus, Erysipelotrichaceae, and Bifidobacterium spp. were increased 12 months after LT. In conclusion, both antibiotics prophylaxis do not affect nor LT outcomes or the risk of intestinal bacterial translocation. However, in the ‘standard ATB’ group, gut microbiota richness after LT was increased, with an increase of beneficial lactic acid- and short-chain fatty acids (SCFA)-producing bacteria and the reduction of harmful Enterobacteriaceae and Klebsiella spp. It could therefore be appropriate to administer standard prophylaxis, reserving the use of ATB-based molecules only in case of complications.

scholarly journals Research and development of Q-Baller -- a spherical wheeled robot

2017 ◽  
Author(s):  
◽  
Jiamin Wang
Keyword(s):  
Control System ◽  
Dynamic Models ◽  
Circuit Board ◽  
Embedded Control ◽  
Wheeled Robot ◽  
Dynamics And Control ◽  
Continuous Gain Scheduling ◽  
Machine Interface ◽  
And Control ◽  
And Robotics

The Spherical Wheeled Robot (Ball-Bot) is a family of robots that can maintain balance standing on a ball and use it as its wheel to move around. In recent years, there have been several successful Ball-Bot designs. We attempt to develop a new spherical wheeled robot product named "Q-Baller" to study its dynamics and control system. The Q-Baller has been designed to ahieve the economic and effective prototyping. A detailed dynamic model of the mechatronic system has been established and analyzed. Control studies have been conducted based on the dynamic models, and new control methods has been proposed to realize continuous gain scheduling. Exclusive simulations have been performed to test the performance of the controllers and reference planning. The Q-Baller hardware has been prototyped and functional. Robotic circuit board, human machine interface and embedded control system have also been developed to make up the full robotic system. The Q-Baller prototype will be tested after the system is fully adjusted, and further researches in control and robotics will be conducted in the future.

scholarly journals Insights into PCDD/Fs and PAHs in Biomass Boilers Envisaging Risks of Ash Use as Fertilizers

2020 ◽  
Vol 10 (14) ◽  
pp. 4951
Author(s):  
Helena Lopes ◽  
Susana Proença
Keyword(s):  
Unburned Carbon ◽  
Fly Ashes ◽  
Power Stations ◽  
Polycyclic Aromatic ◽  
Toxic Equivalents ◽  
One Year ◽  
Definition Of ◽  
And Control ◽  
The Impact ◽  
Biomass Ashes

Since ashes are a possible source of Persistent Organic Pollutants (POPs) contamination, their application in soils must be subject to more study and control. In this scope, feed residual forest biomasses and biomass ashes, collected along one year in four biomass power stations, were characterized mainly for their polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and Polycyclic Aromatic Hydrocarbons (PAHs) contents. The biomasses present concerning levels of Cl (0.04–0.28%) that may lead to PCDD/Fs formation. The biomasses also contain OCDD (29–260 ng/kg) and 1,2,3,4,6,7,8-HpCDD (35 ng/kg) that may contribute to increased Toxic Equivalents (TEQs) of ashes, possibly involving dechlorination and ash enrichment mechanisms. While the WHO2005-TEQs in bottom ashes (14–20 ng TEQ/kg) reaches the proposed limit (20 ng TEQ/kg) for ash use as fertilizers, in fly ashes (35–1139 ng TEQ/kg) the limit is exceeded. PAHs are below 0.02 mg/kg in bottom ashes and 1.5–2.5 mg/kg in fly ashes, complying with the proposed limit of 6 mg/kg. As bottom and fly ash streams may contain different ash flows, a clear definition of ash mixes is required. Correlations between unburned carbon (C), PAHs and PCDD/Fs were not found, which highlights the need for compulsory PCDD/Fs analysis in ashes, independently of their origin, burnout degree or levels of other contaminants. A sensitivity analysis was performed to evaluate the impact of handling non-detected values, which showed more impact for TEQs values close to the proposed regulatory limit of PCDD/Fs. These findings highlight the need to define reporting protocols of analytical results for risk assessments and conformity evaluation.

scholarly journals Dynamics and control of measles in Portugal: Accessing the impact of anticipating the age for the first dose of MMR from 15 to 12 months of age

Vaccine ◽  
2008 ◽  
Vol 26 (19) ◽  
pp. 2418-2427 ◽  
Author(s):  
Ana Cristina Paulo ◽  
Manuel C. Gomes ◽  
M.Gabriela M. Gomes
Keyword(s):  
Dynamics And Control ◽  
And Control ◽  
The Impact

Reconfigurable Fault-Tolerant Tilt-Rotor Quadcopter System

2018 ◽  
Author(s):  
Rumit Kumar ◽  
Siddharth Sridhar ◽  
Franck Cazaurang ◽  
Kelly Cohen ◽  
Manish Kumar
Keyword(s):  
Fault Tolerance ◽  
Dynamic Models ◽  
Fault Tolerant ◽  
Tilt Rotor ◽  
Failure Simulation ◽  
Dynamics And Control ◽  
Space Formulation ◽  
And Control ◽  
Controllability And Observability ◽  
Trim Flight

In this paper, fault-tolerance characteristics of a reconfigurable tilt-rotor quadcopter upon a propeller failure are presented. Traditional quadcopters experience instability and asymmetry about yaw-axis upon a propeller failure but the design and control strategy presented here can handle a complete propeller failure during flight. Fault-tolerance is achieved by means of structural and flight controller reconfiguration. The concept involves conversion of a tilt-rotor UAV into a T-copter. The dynamics and control of the tilt-rotor quadcopter are presented for ideal flight condition and for the reconfigured system in case of propeller failure. Analytical solution for trim flight conditions yielding zero angular rates for the UAV is derived. It has been shown that the structurally reconfigured UAV is controllable and completes the flight mission without much compromise in flight performance. The controllability and observability analysis of the reconfigured system is shown by state space formulation. The flight controllers for both dynamic models are analyzed and the applicability of the proposed concept is presented by propeller failure simulation during the way-point navigation.

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