Thermal energy storage (TES) is widely recognized as a means to integrate renewable energies into the electricity production mix on the generation side, but its applicability to the demand side is ...also possible. In recent decades, TES systems have demonstrated a capability to shift electrical loads from high-peak to off-peak hours, so they have the potential to become a powerful instrument in demand-side management programs (DSM). Thermal storage is a technology that ensures energy security, efficiency and environmental quality. Of particular interest are applications where TES systems help manage the mismatch between availability of renewable electricity and the demand for electricity in buildings where hot water, heating and cooling are delivered by heat pumps and air conditioning for example. Thus this paper demonstrates the state of the art of present applications of thermal storage for demand-side management. A particular focus of this work is the attention paid to the characteristics of DSM and their relationship to different thermal storage systems. If TES effectiveness for the abovementioned applications is demonstrated, TES devices have a small percentage of the potential market. Therefore challenges and guidelines for a development plan are suggested.
Heat pumps are seen as a promising technology for load management in the built environment, in combination with the smart grid concept. They can be coupled with thermal energy storage (TES) systems ...to shift electrical loads from high-peak to off-peak hours, thus serving as a powerful tool in demand-side management (DSM). This paper analyzes heat pumps with radiators or underfloor heating distribution systems coupled with TES with a view to showing how a heat pump system behaves and how it influences the building occupants' thermal comfort under a DSM strategy designed to flatten the shape of the electricity load curve by switching off the heat pump during peak hours (16:00–19:00). The reference scenario for the analysis was Northern Ireland (UK). The results showed that the heat pump is a good tool for the purposes of DSM, also thanks to the use of TES systems, in particular with heating distribution systems that have a low thermal inertia, e.g. radiators. It proved possible to achieve a good control of the indoor temperature, even if the heat pump was turned off for 3 h, and to reduce the electricity bill if a “time of use” tariff structure was adopted.
► Heat pump heating systems with thermal energy storage are considered. ► System behavior is investigated during a DSM strategy for reducing peak energy demand. ► Heat pump heating systems demonstrate to be able to have an active role in DSM programs. ► A TES system must be coupled with the heat pump in presence of low thermal inertia heating distribution systems. ► Central role played by incentives schemes to promote this technology.
Safely achieving the goals of the Paris Climate Agreement requires a worldwide transformation to carbon-neutral societies within the next 30 y. Accelerated technological progress and policy ...implementations are required to deliver emissions reductions at rates sufficiently fast to avoid crossing dangerous tipping points in the Earth’s climate system. Here,we discuss and evaluate the potential of social tipping interventions (STIs) that can activate contagious processes of rapidly spreading technologies, behaviors, social norms, and structural reorganization within their functional domains that we refer to as social tipping elements (STEs). STEs are subdomains of the planetary socioeconomic system where the required disruptive change may take place and lead to a sufficiently fast reduction in anthropogenic greenhouse gas emissions. The results are based on online expert elicitation, a subsequent expert workshop, and a literature review. The STIs that could trigger the tipping of STE subsystems include 1) removing fossil-fuel subsidies and incentivizing decentralized energy generation (STE1, energy production and storage systems), 2) building carbon-neutral cities (STE2, human settlements), 3) divesting from assets linked to fossil fuels (STE3, financial markets), 4) revealing the moral implications of fossil fuels (STE4, norms and value systems), 5) strengthening climate education and engagement (STE5, education system), and 6) disclosing information on greenhouse gas emissions (STE6, information feedbacks). Our research reveals important areas of focus for larger-scale empirical and modeling efforts to better understand the potentials of harnessing social tipping dynamics for climate change mitigation.
Measurements of 21 cm Epoch of Reionization (EoR) structure are subject to systematics originating from both the analysis and the observation conditions. Using 2013 data from the Murchison Widefield ...Array (MWA), we show the importance of mitigating both sources of contamination. A direct comparison between results from Beardsley et al. and our updated analysis demonstrates new precision techniques, lowering analysis systematics by a factor of 2.8 in power. We then further lower systematics by excising observations contaminated by ultra-faint RFI, reducing by an additional factor of 3.8 in power for the zenith pointing. With this enhanced analysis precision and newly developed RFI mitigation, we calculate a noise-dominated upper limit on the EoR structure of Δ2 ≤ 3.9 × 103 mK2 at k = 0.20 h Mpc−1 and z = 7 using 21 hr of data, improving previous MWA limits by almost an order of magnitude.
Abstract
Background
frail patients in any age group are more likely to die than those that are not frail. We aimed to evaluate the impact of frailty on clinical mortality, readmission rate and length ...of stay for emergency surgical patients of all ages.
Methods
a multi-centre prospective cohort study was conducted on adult admissions to acute surgical units. Every patient presenting as a surgical emergency to secondary care, regardless of whether they ultimately underwent a surgical procedure was included. The study was carried out during 2015 and 2016.
Frailty was defined using the 7-point Clinical Frailty Scale. The primary outcome was mortality at Day 90. Secondary outcomes included: mortality at Day 30, length of stay and readmission within a Day 30 period.
Results
the cohort included 2,279 patients (median age 54 years IQR 36–72; 56% female). Frailty was documented in patients of all ages: 1% in the under 40’s to 45% of those aged 80+. We found that each incremental step of worsening frailty was associated with an 80% increase in mortality at Day 90 (OR 1.80, 95% CI: 1.61–2.01) supporting a linear dose–response relationship. In addition, the most frail patients were increasingly likely to stay in hospital longer, be readmitted within 30 days, and die within 30 days.
Conclusions
worsening frailty at any age is associated with significantly poorer patient outcomes, including mortality in unselected acute surgical admissions. Assessment of frailty should be integrated into emergency surgical practice to allow prognostication and implementation of strategies to improve outcomes.
As researchers and ultimately deployers of energy decarbonisation solutions, we collectively see significant but often siloed efforts that in isolation may appear as an appropriate solution to an ...aspect of energy decarbonisation. However, when systemwide thinking is applied, a former attractive solution may become more challenging and, likewise, a less attractive silo may become more appropriate as part of an energy systemwide approach. Thus, the aim of this paper is to combine proposed energy decarbonisation concepts, e.g., electrification, hydrogen, biogas etc., with the status of the system in which they intend to operate, and then highlight the barriers, opportunities, and alternatives that may come into play when the whole system is taken into account. This is a hypothetical study using the city of Belfast, Northern Ireland, UK as an example and reflects, in part, the city’s desire to decarbonise while enhancing its economic prosperity. The “system” is defined as the region boundaries, i.e., Northern Ireland will supply the energy (all or in part) to the city of Belfast. The methodology deployed here therefore is a framework of energy thinking that is the basis of such energy decarbonisation plans at a city-wide level.
Background
Postoperative delirium (POD) is common after surgery. As age is a known risk factor, the increased ageing of the population undergoing surgery emphasizes the importance of the subject. ...Knowledge of other potential risk factors in older patients with surgical gastrointestinal diseases is lacking. The aim here was to collate and synthesize the published literature on risk factors for delirium in this group.
Methods
Five databases were searched (MEDLINE, Web of Science, Embase, CINAHL® and PSYCinfo®) between January 1987 and November 2014. The Newcastle–Ottawa Scale was used to rate study quality. Pooled odds ratios or mean differences for individual risk factors were estimated using the Mantel–Haenszel and inverse‐variance methods.
Results
Eleven studies met the inclusion criteria; they provided a total of 1427 patients (318 with delirium and 1109 without), and predominantly included patients undergoing elective colorectal surgery. The incidence of POD ranged from 8·2 to 54·4 per cent. A total of 95 risk factors were investigated, illustrating wide heterogeneity in study design. Seven statistically significant risk factors were identified in pooled analysis: old age, American Society of Anesthesiologists (ASA) physical status grade at least III, body mass index, lower serum level of albumin, intraoperative hypotension, perioperative blood transfusion and history of alcohol excess. Patients with POD had a significantly increased duration of hospital stay and a higher mortality rate compared with those without delirium.
Conclusion
Delirium is common in older patients undergoing gastrointestinal surgery. Several risk factors were consistently associated with POD.
Several significant risk factors
Objective Our study describes the results from surgical slide tracheoplasty (STP) in children with long segment tracheal stenosis. Methods Demographic and preoperative conditions, operative details, ...and outcome measures, including the need for endoscopic airway intervention and mortality, were collected for children undergoing STP between February 1995 and December 2012. Results One hundred one patients (median age, 5.8 months; range, 5 days-15 years) underwent STP. Seventy-two patients (71.3%) had associated cardiovascular anomalies. Preoperative ventilation was necessary in 56 patients (55.4%), whereas extracorporeal membrane oxygenation was required in 10 patients (9.9%). Abnormal bronchial arborization was present in 39 children (38.6%), which included 13 patients (12.8%) with an anomalous right upper lobe bronchus and 17 patients (16.8%) with tracheal trifurcation. Airway stenosis extended into 1 or both bronchi in 24 patients (23.7%) and preoperative malacia was present in 24 patients (23.7%). STP was extended into the bronchus in 47 patients (46.5%). Overall survival was 88.2% (mortality in 12 patients). Post-STP balloon dilation was necessary in 45 patients (44.6%) and stenting was required in 22 patients (21.8%). Multivariate analysis revealed preoperative extracorporeal membrane oxygenation ( P < .05), preoperative malacia ( P < .001), and bronchial stenosis ( P < .05) to be adverse predictors of survival. Preoperative malacia was a significant risk factor for stenting ( P < .05). Conclusions STP is a versatile and reliable technique associated with low morbidity and mortality when compared with previous strategies for children with long segment tracheal stenosis. The presence of preoperative bronchomalacia is a significant risk factor for death and postoperative stenting.
Here we present a description of the UKCA StratTrop chemical mechanism, which is used in the UKESM1 Earth system model for CMIP6. The StratTrop chemical mechanism is a merger of previously ...well-evaluated tropospheric and stratospheric mechanisms, and we provide results from a series of bespoke integrations to assess the overall performance of the model.
Two's company: Coupling two Dy3 triangles to give Dy6 (see picture; Dy blue, Cl green, O red) leads to a dramatic enhancement of the barrier height to magnetization reversal. The enhancement has been ...rationalized by single‐crystal magnetometry measurements and ab initio calculations.
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