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Microwave curing of repair patches provides an energy efficient technique for rapid concrete repair. It has serious economic potential due to time and energy saving especially for repairs in cold weather which can cause work stoppages. However, the high temperatures resulting from the combination of microwave exposure and accelerated hydration of cementitious repair materials need to be investigated to prevent potential durability problems in concrete patch repairs. This paper investigates the time and magnitude of the peak hydration temperature during microwave curing (MC) of six cement based concrete repair materials and a CEM II mortar. Repair material specimens were microwave cured to a surface temperature of 40-45 °C while their internal and surface temperatures were monitored. Their internal temperature was further monitored up to 24 hours in order to determine the effect of microwave curing on the heat of hydration. The results show that a short period of early age microwave curing increases the hydration temperature and brings forward the peak heat of hydration time relative to the control specimens which are continuously exposed to ambient conditions (20 °C, 60% RH). The peak heat of hydration of normal density, rapid hardening Portland cement based repair materials with either pfa or polymer addition almost merges with the end of microwave curing period. Similarly, lightweight polymer modified repair materials also develop heat of hydration rapidly which almost merges with the end of microwave curing period. The peak heat of hydration of normal density ordinary Portland cement based repair materials, with and without polymer addition, occurs during the post microwave curing period. The sum of the microwave curing and heat of hydration temperatures can easily exceed the limit of about 70 °C in some materials at very early age, which can cause durability problems.

Η έρευνα πραγματοποιήθηκε σε ενήλικες τραχειοστομημένους ασθενείς της ΜΕΘ, οι οποίοι εισήχθησαν στην μελέτη ως αιμοδυναμικά και αναπνευστικά σταθεροί κατά την δοκιμασία αποδέσμευσής τους από τον μηχανικό αερισμό. Όλοι οι ασθενείς διέθεταν παροχή οξυγόνου μέσω διάταξης T-piece και υποβάλλονταν σε παράλληλη εμφύσηση αναπνεόμενου μείγματος μέσω ενδοτραχειακού καθετήρα (TGI), όμοιας συγκέντρωσης (FiO2) και σταθερής ροής στα 6 ή στα 11 L/min, αλλά με τυχαία διαδοχή των πιο πάνω παροχών. Οι ασθενείς παρακολουθούνταν μέσω monitor και τομογράφου εμπέδησης καθ’ όλη τη διάρκεια της δοκιμασίας, κατά την οποία πραγματοποιούνταν μετρήσεις α) πριν την εφαρμογή της TGI, β) κατόπιν 15-λεπτης εφαρμογής της αρχικώς επιλεγμένης παροχής TGI, γ) κατόπιν 15-λεπτης εφαρμογής της δεύτερης κατά σειρά επιλεγμένης παροχής TGI και δ) 15min κατόπιν της επιστροφής του ασθενή στις προ-εφαρμογής TGI συνθήκες.Η εφαρμογή της τεχνικής έδειξε στατιστικά σημαντικές διαφορές στη συγκέντρωση του Οξυγόνου πριν την τοποθέτηση του ενδοτραχειακού καθετήρα (TGI στα 0 L/min) (105 ± 24.6 mmH2O) και μετά την επίδραση του TGI στα 6 και 11 L/min flow (115 ± 26.3 mmH2O and 127 ± 27 mmH2O αντίστοιχα) με p(6L/min)

The EU Waste Framework Directive 2008/98/EC states that all member states should take all necessary measures in order to achieve at least 70% re-use, recycling or other recovery of non-hazardous Construction and Demolition Waste (CDW) by 2020. In response, the Horizon 2020 RE4 project consortium (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) consisting of 12 research and industrial partners across Europe, plus a research partner from Taiwan, was set up. For its success, the approach of the Project was manifold, developing sorting technologies to first improve the quality of CDW-derived aggregate. Simultaneously, CDW streams were assessed for quality and novel applications developed for aggregate, timber and plastic waste in a variety of products including structural and non-structural elements. With all products considered, innovative building concepts have been designed in a bid to improve future reuse and recycling of the products by promoting prefabricated construction methods and modular design to ease future recycling and increase value of the construction industry. The developed technologies and products have been put to the test in different test sites in building a two-storey house containing at least 65% of CDW.

There is a great body of evidence suggesting that in both humans and animal models the microRNA-34/449 (miR-34/449) family plays a crucial role for normal testicular functionality as well as for successful spermatogenesis, regulating spermatozoa maturation and functionality. This review and critical analysis aims to summarize the potential mechanisms via which miR-34/449 dysregulation could lead to male infertility. Existing data indicate that miR-34/449 family members regulate ciliogenesis in the efferent ductules epithelium. Upon miR-34/449 dysregulation, ciliogenesis in the efferent ductules is significantly impaired, leading to sperm aggregation and agglutination as well as to defective reabsorption of the seminiferous tubular fluids. These events in turn cause obstruction of the efferent ductules and thus accumulation of the tubular fluids resulting to high hydrostatic pressure into the testis. High hydrostatic pressure progressively leads to testicular dysfunction as well as to spermatogenic failure and finally to male infertility, which could range from severe oligoasthenozoospermia to azoospermia. In addition, miR-34/449 family members act as significant regulators of spermatogenesis with an essential role in controlling expression patterns of several spermatogenesis-related proteins. It is demonstrated that these microRNAs are meiotic specific microRNAs as their expression is relatively higher at the initiation of meiotic divisions during spermatogenesis. Moreover, data indicate that these molecules are essential for proper formation as well as for proper function of spermatozoa per se. MicroRNA-34/449 family seems to exert significant anti-oxidant and anti-apoptotic properties and thus contribute to testicular homeostatic regulation. Considering the clinical significance of these microRNAs, data indicate that the altered expression of the miR-34/449 family members is strongly associated with several aspects of male infertility. Most importantly, miR-34/449 levels in spermatozoa, in testicular tissues as well as in seminal plasma seem to be directly associated with severity of male infertility, indicating that these microRNAs could serve as potential sensitive biomarkers for an accurate individualized differential diagnosis, as well as for the assessment of the severity of male factor infertility. In conclusion, dysregulation of miR-34/449 family detrimentally affects male reproductive potential, impairing both testicular functionality as well as spermatogenesis. Future studies are needed to verify these conclusions.

Background and Objectives: Clinicians are called to overcome age-related challenges in decision making during In Vitro Fertilization (IVF) treatment. The aim of this study was to investigate the possible impact of a single calendar year difference among patients aged 34, 35 and 36 on IVF outcomes. Materials and Methods: Medical records between 2008 and 2019 were analyzed retrospectively. The study group consisted of women diagnosed with tubal factor infertility. Sample size was divided in three categories at 34, 35 and 36 years of age. Embryo transfer including two blastocysts was performed for every patient. Comparisons were performed regarding hormonal profile, response to stimulation, quality of transferred embryos, positive hCG test and clinical pregnancy rate. Results: A total of 706 women were eligible to participate. Two-hundred and forty-eight women were 34, 226 were 35 while the remaining 232 were 36 years old. Regarding the hormonal profile, the number of accumulated oocytes and the quality of embryos transferred, no statistically significant difference was documented between the three age groups. Women aged 34 and 35 years old indicated a significantly increased positive hCG rate in comparison to women aged 36 years old (p-value = 0.009, p-value = 0.023, respectively). Women aged 34 and 35 years old presented with a higher clinical pregnancy rate in comparison to those aged 36 years old (p-value = 0.04, p-value = 0.05, respectively). Conclusion: A calendar year difference between patients undergoing IVF treatment at 34 or 35 years of age does not appear to exert any influence regarding outcome. When treatment involves patients above the age of 35, then a single calendar year may exert considerable impact on IVF outcome. This observation indicates that age 35 may serve as a valid cut-off point regarding IVF outcome.

Background: The purpose of the study was to investigate the responsibilities and frequency of clinical procedures that physiotherapists perform within the intensive care unit (ICU) in Greece, along with the level of education and training of these physiotherapists. Methods: Physiotherapists who work in general ICUs of hospitals were invited to complete a developed questionnaire. The questionnaire consisted of 83 items, of closed and opened–ended format. Items for service provision and physiotherapists’ employment were included, along with participants’ involvement in respiratory care, early mobilisation and the use of the ICU equipment. Results: One hundred forty physiotherapists completed the questionnaire. Seventy-three respondents (52%) reported working in ICU in Athens and 67 (48%) in other cities of Greece. Almost all the physiotherapists’ performed early mobilisation and respiratory techniques; although the frequency of procedures and use of equipment were variable. Sixty-one (44%) and 70 (50%) respondents participated in the weaning procedure and mobilised the patient whilst using the ventilator, respectively. Conclusion: The physiotherapists are from ICUs all over Greece. The results reflect the differences among the procedures that physiotherapists perform, regarding early mobility and respiratory physiotherapy. The results indicate the need for a national up-to-date job description of the physiotherapy services in ICUs in Greece.

Construction and Demolition Waste (CDW) accounts for approximately 25-30% of all waste generated across Europe each year. However, Waste Framework Directive 2008/98/EC requires from all EU member states to achieve at least 70% re-use, recycling or other recovery of non-hazardous CDW by 2020. In response, the Horizon 2020 RE4 Project (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) consortium was set up. Its main aims are to assess the quality of various CDW fractions (e.g. mineral aggregate, timber, plastics, silt & clay), improve the quality of mineral aggregates and develop different building elements/components which contain at least 65% of CDW. Innovative building concepts will also be developed in an effort to improve recycling rates of future buildings through the use of prefabrication and modular design. The developed products and technologies will be assessed in a number of test sites by building 2-storey demonstration houses.

Different proprietary repair materials and a CEM II mortar were used to characterise the relationship between the main parameters of microwave curing (power, curing time, temperature rise and volume). The time-temperature-power relationships are linear for normal, non-rapid setting repair materials cured within the recommended temperature range taking account of temperature variation and heat of hydration. A general relationship between the microwave curing parameters of power, temperature rise, curing time and repair volume has been derived. It has been used to design and operate a prototype system. Steel reinforcement in the repair remains free from arcing under microwave exposure.

BACKGROUND: This study aimed to examine the relationship between hand-grip force and maximum inspiratory pressure (PImax) in healthy young and middle-age individuals. METHODS: All individuals underwent assessment of inspiratory muscle strength by maximum inspiratory pressure using a U-type water manometer and evaluation of hand-grip force by a hydraulic hand dynamometer. RESULTS: The correlation of PImax and hand-grip force was strong (r = 0.76). A multilinear regression model was built to investigate the ability of various parameters, such as hand-grip force, sex, and body mass index measurements, to predict PImax. PImax can be accurately predicted by 80% (r = 0.76) with a simple equation of easily evaluable factors, such as hand-grip force, body mass index, and sex. CONCLUSION: The results showed significant correlation between hand flexors' force and strength of inspiratory muscles in healthy individuals. This appears to be an easy way to evaluate the results indirectly and can help to assess the relationship between hand flexor and inspiratory muscle capacity, especially the diaphragm. Our study should be viewed as a hypothesis-generating one, and further studies are required in the population of critically ill or difficult-to-wean patients. (ClinicalTrials.gov registration [NCT02423616][1].) [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02423616&atom=%2Frespcare%2F61%2F7%2F925.atom

This paper investigates the effect of microwave curing on the bond strength of steel reinforcement in concrete repair. Pull-out tests on plain mild steel reinforcement bars embedded in four repair materials in 100 mm cube specimens were performed to determine the interfacial bond strength. The porosity and pore structure of the matrix at the steel interface, which influence the bond strength, were also determined. Test results show that microwave curing significantly reduces the bond strength of plain steel reinforcement. The reduction relative to normally cured (20 °C, 60% RH) specimens is between 21 and 40% with low density repair materials and about 10% for normal density cementitious mortars. The corresponding compressive strength of the matrix also recorded similar reduction and microwave curing resulted in increased porosity at the interface transition zone of the steel reinforcement. A unique relationship exists between bond strength and both compressive strength and porosity of all matrix materials. Microwave curing reduced shrinkage but despite the wide variation in the shrinkage of the repair mortars, its effect on the bond strength was small. The paper provides clear correlations between the three parameters (compressive strength, bond strength and porosity), which are common to both the microwave and conventionally cured mortars. Therefore, bond-compressive strength relationships used in the design of reinforced concrete structures will be also valid for microwave cured elements.

The overall success and long-term durability of a patch repair is significantly influenced by the bond developed at the interface between the concrete substrate and the repair material. In turn, the bond strength is influenced by the topography (roughness) of the substrate surface after removal of the defective concrete. However, different removal methods of defective concrete produce substrate surfaces with different topographies. Hence, the ability to measure and characterise the topography of substrate surfaces is of great importance for evaluating the effectiveness of different removal methods. In this paper, the effect of two removal methods: electric chipping hammers and Remote Robotic Hydro-erosion (RRH) on the surface roughness is investigated through the use of a prototype non-contact (optical) laser interferometry measuring device. Laboratory results show that the above equipment can be used to characterise substrate roughness and confirm the ability of RRH to create rougher surfaces as opposed to chipping hammers.

BACKGROUND: Nasotracheal suctioning (NTS) is accomplished by inserting a suction catheter into the trachea through the nasopharynx. It is a useful procedure in critically ill patients whose ability to cough and mobilize secretions is impaired. Ιt was assumed that using a suction catheter with an angular tip would facilitate entry into the trachea. The primary outcome was the success rate and the ease of insertion by using a curved edge catheter (Tiemann type) compared with a conventional suction catheter. The secondary outcome was the monitoring of subject's vital signs during the intervention. METHODS: Non-intubated subjects hospitalized in 2 adult ICUs underwent 2 consecutive NTSs each, using either a 14 French curved edge catheter or a 14 French conventional suction catheter, randomly. RESULTS: Twenty subjects with a mean age of 75.5 y were enrolled for a time period of 5 months. The tracheal access success rate was 19/52 (successful/unsuccessful attempts) using a curved edge catheter (36.5%, 95% CI 23.6–51.0%) compared with 12/130 (9.2%, 95% CI 4.8–15.5%) using a conventional suction catheter. The insertion was 5.6 times more likely to be achieved by using a curved edge catheter (odds ratio 5.66, 95% CI 2.49–12.84, P < .001). The number of attempts required to succeed in the insertion was significantly lower when using a curved edge catheter than when using a conventional suction catheter (for nasopharynx, median [range] of 1 [1] versus 2.5 [8], P = .001; for trachea, median [range] of 2 [9] versus 9 [9], P = .002). The time required for successful insertion into the nasopharynx and trachea was significantly shorter when using a curved edge catheter than when using a conventional suction catheter (for nasopharynx, median [range] of 3 [11] s versus 5.3 [18] s, P = .038; for trachea, median [range] of 6 [27] s versus 20 [25] s, P = .002). The traumatic rate (percentage of catheters with blood present on the tip) was exactly the same for both catheters (30%). CONCLUSIONS: It is more likely that tracheal access will be achieved using a curved edge catheter. A shorter process time and fewer attempts are required for successful NTS using a curved edge catheter, and it seems to be an equally safe procedure. (ClinicalTrials.gov registration [NCT02261428][1].) [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02261428&atom=%2Frespcare%2F60%2F12%2F1826.atom

The EU Waste Framework Directive 2008/98/EC states that all member states should take all necessary measures in order to achieve at least 70% re-use, recycling or other recovery of non-hazardous Construction and Demolition Waste (CDW) by 2020. In response, the Horizon 2020 RE4 project consortium (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) consisting of 12 research and industrial partners across Europe, plus a research partner from Taiwan, was set up. For its success, the approach of the project was manifold, developing sorting technologies to first improve upon the quality of recycled aggregate. Simultaneously, CDW streams were assessed for quality and novel applications developed for timber, aggregate, and plastic waste in a variety of products including structural (e.g. beams, columns, slabs) and non-structural (e.g. building blocks, insulation panels, tiles) elements. With all products considered, innovative building concepts have been designed in a bid to improve future recycling of the products by promoting prefabricated construction methods and modular design to ease future recycling and increase value of the construction industry. The developed technologies and products will be put to the test in different test sites in building a 2 storey house containing at least 65% of CDW in the next 6 to 12 months.

The bond strength between a concrete substrate and repair patch is critical to its durability. This paper investigates the effect of microwave curing the freshly applied repair, for 45 min at 132 Watts, on the 28 day bond strength between substrate concrete and different commercial repair materials. The repairs were applied at different ambient temperatures of 20, 10, 2 and −5 °C. Tensile split tests on repaired cube specimens were performed to determine the interfacial bond strength. The ability of microwave curing to prevent the detrimental effects of freezing at early age on the bond and compressive strength of repair patches is investigated. Experimental results show that microwave curing prevents loss of long term (28 day) repair/substrate bond strength of repair materials applied at freezing temperatures (−5 °C), relative to the repairs applied at higher temperatures (2–20 °C), except one lightweight repair formulation. In comparison, the control samples (non-microwave cured) of repairs applied at −5 °C suffered severe loss of bond strength and compressive strength due to early age freezing. In addition, no adverse effects on the bond strength and a small reduction of 6.75% in the 28 day compressive strength are observed in the early age microwave cured repairs applied at ambient temperatures of 2–20 °C. The repair/substrate bond strength is independent of the compressive strength of the repair material at all temperatures of repair application. Microwave curing can accelerate the concrete repair process and facilitate construction activity in cold weather.

This paper presents preliminary results from the development of a novel CDW robotic sorting system. Data from hyperspectral cameras and reflectance sensors will be combined to produce a 2D heat map for object classification by an algorithm which is under development. A 6 Degrees of Freedom robotic arm will be utilised in handling and sorting the CDW particles. The final goal is to achieve purity higher than 90% for each fraction. Different material classes will be sorted and recycled in prefabricated construction applications. Preliminary results indicate that coupling the hyperspectral information and the robotic technology allow to achieve high-quality sorting of CDW.