Minimum inhibitory and bacterial concentrations of theaflavin and synergistic combinations with epicatechin and quercetin against clinical isolates of Stenotrophomonas Maltophilia

Stenotrophomonas maltophilia is an important nosocomial pathogen with intrinsic resistance to multiple antibiotics. Previous investigations have shown flavanols from black tea to possess antibacterial activity. This study describes the determination of minimum inhibitory concentrations and minimum bactericidal concentration for theaflavin independently and in formulations with the polyphenols epicatechin and quercetin against nine clinical isolates of Stenotrophomonas maltophilia and the control isolate NCTC 130141 via the microtitre assay. The results demonstrate that theaflavin has strong antibacterial activity and also shows significant synergism with epicatechin and quercetin. The minimum inhibitory concentrations of the isolates range between 200-400 g/mL for theaflavin and 100-200 g/mL for both theaflavin:epicatechin and theaflavin:quercetin combinations. The minimum bactericidal concentrations were discovered to be a 2 fold increase on those of the minimum inhibitory concentrations. The research highlights the potential use of polyphenols for the clinical treatment of highly antibiotic resistant bacteria.

Does the UK minimum wage reduce employment? A meta-regression analysis

The employment effect from raising the minimum wage has long been studied but remains in dispute. Our meta-analysis of 236 estimated minimum wage elasticities and 710 partial correlation coefficients from 16 UK studies finds no overall practically significant adverse employment effect. Unlike US studies, there seems to be little, if any, overall reporting bias. Multivariate meta-regression analysis identifies several research dimensions that are associated with differential employment effects. In particular, the residential home care industry may exhibit a genuinely adverse employment effect.

A fault detection scheme for time-delay systems using minimum-order functional observers

This paper presents a method for designing residual generators using minimum-order functional observers to detect actuator and component faults in time-delay systems. Existence conditions of the residual generators and functional observers are first derived, and then based on a parametric approach to the solution of a generalized Sylvester matrix equation, we develop systematic procedures for designing minimum-order functional observers to detect faults in the system. The advantages of having minimum-order observers are obvious from the economical and practical points of view as cost saving and simplicity can be achieved, particularly when dealing with high-order complex systems. Extensive numerical examples are given to illustrate the proposed fault detection scheme. In all the numerical examples, we design minimum-order residual generators and functional observers to detect faults in the system.

Fighting fire and fatigue: sleep quantity and quality during multi-day wildfire suppression

This study examined firefighters' sleep quantity and quality throughout multi-day wildfire suppression, and assessed the impact of sleep location, shift length, shift start time and incident severity on these variables. For 4 weeks, 40 volunteer firefighters' sleep was assessed using wrist actigraphy. Analyses revealed that the quantity of sleep obtained on fire days was restricted, and pre- and post-sleep fatigue ratings were higher, compared to non-fire days. On fire days, total sleep time was less when: (i) sleep location was in a tent or vehicle, (ii) shifts were greater than 14 h and (iii) shifts started between 05:00 and 06:00 h. This is the first empirical investigation providing objective evidence that firefighters' sleep is restricted during wildfire suppression. Furthermore, sleep location, shift length and shift start time should be targeted when designing appropriate controls to manage fatigue-related risk and preserve firefighters' health and safety during wildfire events. Practitioner Summary: During multi-day wildfire suppression, firefighters' sleep quantity was restricted, and pre- and post-sleep fatigue ratings were higher, compared to non-fire days. Furthermore, total sleep time was less when: (i) sleep occurred in a tent/vehicle, (ii) shifts were >14 h and (iii) shifts started between 05:00 and 06:00 h.

Sleep quantity and quality is not compromised during planned burn shifts of less than 12 h

Planned burning is a preventative strategy aimed at decreasing fuel loads to reduce the severity of future wildfire events. During planned burn operations, firefighters can work long shifts. Furthermore, remote burning locations may require firefighters to sleep away from home between shifts. The existing evidence surrounding firefighters' sleep during such operations is exclusively anecdotal. The aims of the study were to describe firefighters' sleep during planned burn operations and evaluate the impact of the key operational factors (shift start time, shift length and sleeping location) that may contribute to inadequate sleep. Thirty-three salaried firefighters were recruited from Australia's fire agencies and sleep was measured objectively using wrist actigraphy for four weeks. All variables were examined in two conditions: (1) burn days, and (2) non-burn days. Time in bed, total sleep time, sleep latency and sleep efficiency were evaluated objectively. Subjective reports of pre- and post-sleep fatigue, sleep location, sleep quality, sleep quantity, number of times woken and sleep timing were also recorded. Analyses revealed no differences in measures of sleep quantity and quality when comparing non-burn and burn days. Total sleep time was less when planned burn shifts were >12 h. However, on burn days, work shift start time as well as sleeping location did not impact firefighters' sleep quantity. Self-reported levels of pre- and post-sleep fatigue were greater on burn days compared to non-burn days. These findings indicate that sleep quantity and quality are not compromised during planned burn operations <12 h in duration.