In recent years, energy efficiency and thermal comfort in historic buildings have become high-interest topics among scholars. Research has demonstrated that retrofitting buildings to current energy ...efficiency and thermal comfort standards is essential for improving sustainability and energy performance and for maintaining built heritage of historic structures. This study is an extensive overview of the literature surrounding this topic. This paper summarizes the different methods and techniques that have been used around the world to achieve performance refurbishments. Articles are organized based on the different building types used as case studies (residential, religious, academic and palace, museums, libraries and theaters, urban areas, and others). The results reveal that residential, religious and museum building types, especially from the last two centuries, have been most often used as case studies. Moreover, Europe, particularly Italy, is leading the research. The aim of this note is to demonstrate the feasibility of maintaining built heritage values of historic buildings while achieving significant improvements in their energy efficiency and thermal comfort.
Antibiotic-resistant organisms enter into water environments from human and animal sources. These bacteria are able to spread their genes into water-indigenous microbes, which also contain resistance ...genes. On the contrary, many antibiotics from industrial origin circulate in water environments, potentially altering microbial ecosystems. Risk assessment protocols for antibiotics and resistant bacteria in water, based on better systems for antibiotics detection and antibiotic-resistance microbial source tracking, are starting to be discussed. Methods to reduce resistant bacterial load in wastewaters, and the amount of antimicrobial agents, in most cases originated in hospitals and farms, include optimization of disinfection procedures and management of wastewater and manure. A policy for preventing mixing human-originated and animal-originated bacteria with environmental organisms seems advisable.
Antibiotics are among the most successful drugs used for human therapy. However, since they can challenge microbial populations, they must be considered as important pollutants as well. Besides being ...used for human therapy, antibiotics are extensively used for animal farming and for agricultural purposes. Residues from human environments and from farms may contain antibiotics and antibiotic resistance genes that can contaminate natural environments. The clearest consequence of antibiotic release in natural environments is the selection of resistant bacteria. The same resistance genes found at clinical settings are currently disseminated among pristine ecosystems without any record of antibiotic contamination. Nevertheless, the effect of antibiotics on the biosphere is wider than this and can impact the structure and activity of environmental microbiota. Along the article, we review the impact that pollution by antibiotics or by antibiotic resistance genes may have for both human health and for the evolution of environmental microbial populations.
The article reviews the current knowledge on the effects that pollution by antibiotics and antibiotic resistance genes may have for the microbiosphere.
Broadband Radar Cross-Section Reduction Using AMC Technology Iriarte Galarregui, Juan Carlos; Tellechea Pereda, Amagoia; Martinez de Falcon, Jose Luis ...
IEEE transactions on antennas and propagation,
12/2013, Letnik:
61, Številka:
12
Journal Article
Recenzirano
Odprti dostop
This paper presents the design, fabrication, and characterization of a planar broadband chessboard structure to reduce the radar cross-section (RCS) of an object. The chessboard -like configuration ...is formed by combining two artificial magnetic conductor (AMC) cells. The bandwidth limitations intrinsic to AMC structures are overcome in this work by properly selecting the phase slope versus frequency of both AMC structures. A 180 ° phase difference has been obtained over more than 40% frequency bandwidth with a RCS reduction larger than 10 dB. The influence of the incidence angle in the working bandwidth has been performed. A good agreement between simulations and measurements is achieved.
Polycyclic aromatic hydrocarbons (PAHs) are compounds widespread in the environment, many of them showing carcinogenic effects. These compounds can reach the food chain by different ways and, ...therefore, the analysis of PAHs in food is a matter of concern. This article reviews the extraction methodologies together with the separation and detection techniques which are currently applied in the determination of PAHs in food and beverages. Specific extraction conditions, performance characteristics, chromatographic and detection parameters are discussed. A review of the occurrence of these compounds in the matrixes under study is also provided.
The trend in power electronic applications is to reach higher power density and higher efficiency. Currently, the wide band-gap devices such as silicon carbide MOSFET (SiC MOSFET) are of great ...interest because they can work at higher switching frequency with low losses. The increase of the switching speed in power devices leads to high power density systems. However, this can generate problems such as overshoots, oscillations, additional losses, and electromagnetic interference (EMI). In this paper, a novel active gate driver (AGD) for improving the SiC MOSFET switching trajectory with high performance is presented. The AGD is an open-loop control system and its principle is based on gate energy decrease with a gate resistance increment during the Miller plateau effect on gate-source voltage. The proposed AGD has been designed and validated through experimental tests for high-frequency operation. Moreover, an EMI discussion and a performance analysis were realized for the AGD. The results show that the AGD can reduce the overshoots, oscillations, and losses without compromising the EMI. In addition, the AGD can control the turn-on and turn-off transitions separately, and it is suitable for working with asymmetrical supplies required by SiC MOSFETs.
We aimed to describe the differences and similarities between patients with chronic obstructive airway disease classified on the basis of classical diagnostic labels (asthma, chronic obstructive ...pulmonary disease (COPD), or asthma-COPD overlap (ACOS)) or according to the underlying inflammatory pattern (Th-2 signature, either Th-2-high or Th-2-low).We performed a cross-sectional study of patients aged ≥40 years and with a post-bronchodilator forced expiratory volume in 1 s to forced vital capacity ratio ≤0.7 with a previous diagnosis of asthma (non-smoking asthmatics (NSA)), COPD or ACOS, the latter including both smoking asthmatics (SA) and patients with eosinophilic COPD (COPD-e). Clinical, functional and inflammatory parameters (blood eosinophil count, IgE and exhaled nitric oxide fraction (
)) were compared between groups. Th-2 signature was defined by a blood eosinophil count ≥300 cells·μL
and/or a sputum eosinophil count ≥3%.Overall, 292 patients were included in the study: 89 with COPD, 94 NSA and 109 with ACOS (44 SA and 65 with COPD-e). No differences in symptoms or exacerbation rate were found between the three groups. With regards the underlying inflammatory pattern, 94 patients (32.2%) were characterised as Th-2-high and 198 (67.8%) as Th-2-low. The Th-2 signature was found in 49% of NSA, 3.3% of patients with COPD, 30% of SA and 49.3% of patients with COPD-e. This classification yielded significant differences in demographic, functional and inflammatory characteristics.We conclude that a classification based upon the inflammatory profile, irrespective of the taxonomy, provides a more clear distinction of patients with chronic obstructive airway disease.
Oxaliplatin was the first platinum drug with proven activity against colorectal tumors, becoming a standard in the management of this malignancy. It is also considered for the treatment of pancreatic ...and gastric cancers. However, a major reason for treatment failure still is the existence of tumor intrinsic or acquired resistance. Consequently, it is important to understand the molecular mechanisms underlying the appearance of this phenomenon to find ways of circumventing it and to improve and optimize treatments. This review will be focused on recent discoveries about oxaliplatin tumor-related resistance mechanisms, including alterations in transport, detoxification, DNA damage response and repair, cell death (apoptotic and nonapoptotic), and epigenetic mechanisms.
Introduction
Device infections constitute a major complication of transvenous pacemakers. Mechanical heart valves (MHV) increase the risk of infective endocarditis (IE) and pacemaker infection, ...requiring lifelong vitamin K‐antagonists (VKA), which may affect patient management. Leadless pacemakers (LP) are associated with low infection rates, posing an attractive option in MHV patients requiring permanent pacing. This study describes outcomes following LP implantation in patients with MHV.
Methods
This is a multicenter, observational, retrospective study including consecutive patients implanted with an LP at 5 centers between June 2015 and January 2020. Procedural outcomes, antithrombotic management, complications, performance during follow‐up and episodes of bacteremia and IE were compared between patients with and without an MHV (MHV and non‐MHV groups).
Results
Four hundred fifty‐nine patients were included (74 in the MHV group, 16.1%, and 385 in the non‐MHV group, 83.9%). Procedural outcomes and acute electrical performance were comparable between groups. Vascular complications and cardiac perforation occurred in 2.7 versus 2.3% (p = 1) and 0% versus 0.8% (p = 1) in the MHV group and non‐MHV group. One case of IE occurred in the MHV group and 2 in the non‐MHV group. In MHV patients, uninterrupted VKA was used in 83.8%, whereas 16.2% were heparin‐bridged. Vascular complication or tamponade occurred in 1 (8.3%) MHV heparin‐bridged patient versus 1 (1.6%) MHV uninterrupted VKA patient (p = .3).
Conclusion
LP implantation outcomes in MHV patients are comparable to the general LP population. Device‐related infections are rare following LP implantation, including in patients with MHV. In the MHV group, periprocedural anticoagulation management was not associated with significantly different rates of tamponade or vascular complication.
Antibiotic resistance is a threat to human and animal health worldwide, and key measures are required to reduce the risks posed by antibiotic resistance genes that occur in the environment. These ...measures include the identification of critical points of control, the development of reliable surveillance and risk assessment procedures, and the implementation of technological solutions that can prevent environmental contamination with antibiotic resistant bacteria and genes. In this Opinion article, we discuss the main knowledge gaps, the future research needs and the policy and management options that should be prioritized to tackle antibiotic resistance in the environment.
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