bluuebunny/crossref_metadata_2025 huggingface dataset:
Inventory of environmental certifications throughout the world
Authors: Lempereur V. , Balazard M. , Herbin C.
Published: October 2019

During the XXth century, intensive agricultural practices has been spread and allowed an important increase of productivity, especially thanks to scientific and technical innovations. Nevertheless, this change had consequences on biodiversity, quality of ecosystems and landscapes by a simplification of wine areas. In addition, sociocultural pressures toward agricultural practices had become stronger and stronger. In response, many mobilizations had begun to emerge, especially in the wine sector. For some years, we observed a real dynamic of the sector at the environmental level with the creation of many approaches which are promoting sustainable wine practices. These certifications are various and come up to consumers' wishes for products which are respectful of environment. They can be carried by productors associations, wine regions, cooperatives, wine companies or public authorities. We have inventoried in 22 countries a total of 54 environmental certifications among which 33 are dedicated to viticulture. We categorize them through: the scale (local, national, international), the area (vine, vine and wine, multi agricultural sector), the subjects treated (environment, economic, social) and the dynamic of the approach (voluntary, compulsory, individual or collective). This article informs and sensitizes the actors of wine sector to the diversity of environmental approaches in the world.
Nichts ist mehr wie es vorher war
Authors: Seel Helga
Published: October 2019

Liebe Leserinnen und Leser,

jährlich erleiden mehr als 270 000 Menschen überwiegend unfallbedingt
eine Schädelhirnverletzung unterschiedlichsten Schweregrades. Schlaganfälle,
entzündliche Hirnerkrankungen, Hirntumorerkrankungen führen jährlich
bei über 500 000 Menschen zu einer Hirnschädigung. Insgesamt kann davon
ausgegangen werden, dass in Deutschland ungefähr 800 000 Menschen mit den
Folgen einer Hirnschädigung leben, viele davon mit dauerhaften Einschränkungen
der körperlichen und geistigen Leistungsfähigkeit.
Zehn Jahre Hautkrebsscreening in Deutschland – Leuchtturmfunktion, Probleme und Verbesserungsansätze – Daten einer großen Hautarztpraxis
Authors: Ziegler P.
Published: October 2019

Von 2008 – 2018 wurden ca. 40 000 Hautkrebsscreenings durchgeführt und die Daten analysiert.

Es zeigte sich zum einen eine hochsignifikant steigende Zunahme von epithelialen malignen Tumoren um mehr als das Doppelte zwischen 2009 – 2018. Bei Patienten des gesetzlichen Hautkrebsscreenings konnte bei jedem 10. Patienten „weißer Hautkrebs“ diagnostiziert werden, 1,2 % der Patienten litten unter einem malignen Melanom, wobei 50 % davon in situ waren. Eine statistische Analyse der dysplastischen Nävi erbrachte eine höchst signifikante Differenz zwischen Patienten des gesetzlichen Screenings (54,2 Jahre) und Patienten unter 35 Jahren (23,4 Jahre). Die jüngere Patientengruppe (< 35 Jahre) wies fast doppelt so häufig histologisch nachgewiesene dysplastische Nävi als die Patienten des gesetzlichen Screenings (> 35 Jahre) auf. Dies könnte ein früheres Screening ab 20 Jahren befürworten, um mögliche Risikogruppen rechtzeitig zu identifizieren. Die Senkung der Melanommortalität als einziger Erfolgsparameter ist allerdings kritisch zu hinterfragen.
Centaurium Erythraea Extracts Exert Vascular Effects through Endothelium- and Fibroblast-dependent Pathways
Authors: Chda Alae , El Kabbaoui Mohamed , Fresco Paula , Silva Dany , Gonçalves Jorge , Oliveira Andreia P. , Andrade Paula B. , Valentão Patrícia , Tazi Abdelali , El Abida Kaouakib , Bencheikh Rachid
Published: October 2019

Centaurium erythraea is a plant used in traditional medicine for several cardiovascular disorders, namely hypertension, but there is no scientific evidence able to provide a molecular basis for its claimed antihypertensive effects. After a preliminary screen of extracts obtained from sequential extraction of C. erythraea aerial parts, effects of the methanolic fraction (MFCE) on changes in perfusion pressure of isolated rat mesenteric vascular bed (MVB) and in rat cardiac fibroblasts proliferation were investigated, gathering information on the mechanisms involved in endothelium-dependent effects and their dependence on a pro-proliferative stimulus. The HPLC-DAD determination of the phenolics content of MFCE revealed the presence of 22 phenolic compounds. MFCE reduced (63.3 ± 3.9%; n = 4) perfusion pressure in MVB and almost completely abrogated the Ang II-induced increase in cardiac fibroblasts proliferation. Reduction of the perfusion pressure caused by MFCE was endothelium-dependent and occurred in parallel with an increase in NO release. These effects were inhibited by muscarinic receptor antagonists, by L-NAME (a NO synthase inhibitor), and by ODQ (a soluble guanylate cyclase inhibitor). Experiments revealed that effects required the involvement of K+ channels, being inhibited by tetraethylamonium (TEA; a Ca2+ activated K+ channels inhibitor) and by glibenclamide (an ATP-sensitive K+ channels inhibitor). In conclusion, extracts from C. erythraea, particularly the compounds present in the MFCE, induce endothelium-dependent vasodilation and prevent fibroblast proliferation induced by angiotensin II, which can account for the claimed antihypertensive effects of C. erythraea in traditional medicine.
A New Synthetic Pathway to Symmetric Bisubstituted Naphthoquinones
Authors: Migulin Vasily A.
Published: October 2019

straightforward and practical synthesis of 2,3-diiodo-1,4-naphthoquinone is reported. Based on the prepared diiodide, a new synthetic approach to symmetric bisubstituted 1,4-naphthoquinones via double Suzuki–Miyaura reaction at room temperature has been researched and developed. The presented general method combines broad-spectrum applicability, efficiency, and simplicity providing target materials in good to quantitative yields.
Intermuscular S-ICD Implantation in Pediatric Patients
Authors: Ferreiro-Marzal Andrea , Rodríguez-Serrano Fernando , Esteban-Molina María , González-Vargas Teresa , Perin Francesca , Garrido Jose Manuel
Published: October 2019

The use of conventional implantable cardioverter-defibrillators (ICDs) in children presents important technical challenges. We present the surgical technique necessary to adapt the subcutaneous ICD (S-ICD) implantation designed for adults, to children, including patients weighing less than 20 kg. The implant procedure implies a two-incision technique and interfascial serratus anterior–latissimus dorsi dissection to accommodate the device. S-ICD implantation was successfully performed in three patients of 19, 28, and 24 kg, respectively, two of them suffered cardiorespiratory arrest. Intermuscular thoracic implantation of S-ICD might represent an effective strategy for primary or secondary prevention of sudden cardiac death in pediatric patients.
Outcome of “DESTITUTE” Head Injury Patients at a Tertiary Care Neurosurgical Centre: A KGMU Experience of 10 Years
Authors: Digarse Rohan Dilip , Ojha Bal Krishna , Chandra Anil , Srivastava Chhitij , Singh Sunil Kumar
Published: October 2019

Introduction Many patients are admitted to hospitals as destitute or unknown, after having met with accidents. What happens to these patients after admission is not much reported in world literature. With the ever increasing number of road traffic accidents (RTAs), a significant number of such patients are reported worldwide.

Material and Methods We conducted a retrospective analysis of the departmental case records of destitute patients from January 2009 till December 2018 in our institute. The mode of presentation, demographic profile, computed tomography scan findings, hospital course, and outcome at discharge were analyzed.

Results Out of 128 patients, there were 114 (89.1%) male patients, maximum being in the 21 to 30 years age group. The mean age was 36.4 years with ages ranging from 10 to 70 years. The average length of stay in hospital was of approximately 6 days with maximum being 37 days. The main cause of head injury was RTA in 66 patients (51.5%). Majority, that is, 84 patients, had a Glasgow Coma Scale score of < 8 at admission. Forty-two head injury patients were operated in all, while the rest were managed conservatively. Forty-nine (38.2%) patients died in hospital, and 44 (34.3%) patients had good recovery. During treatment, 16 (12.5%) patients took discharge against medical advice, while identity of 63 (49.2%) patients could be established out of which 5 (3.9%) patients were either discharged to home while 51 (39.8%) patients were referred to their district hospital. Two patients (1.5%) remained unknown and were sent to destitute homes for rehabilitation.

Conclusion Unknown head injury patients are usually neglected and their outcome is poorer in comparison to other patients. Their management is fraught with challenges. They need special care for which staff should be well trained and hospital must have economic resources and a good network of social workers.
Endoscopic Endonasal Odontoidectomy
Authors: Joshi Krishna , Woodard Troy , Borghei-Razavi Hamid , Recinos Pablo F. , Kshettry Varun R.
Published: October 2019

Odontoidectomy is a standard procedure employed in the treatment of irreducible, compressive ventral pathologies of the craniovertebral junction (CVJ). The traditionally used transoral route is often challenging due to the increased depth of the surgical corridor and risk of injuries to the soft tissues in the oral cavity. The emergence of endoscopic endonasal (EE) surgery has provided an attractive alternative route to the traditional treatment algorithm, and it has the advantages of avoiding complications related to tongue swelling, tracheal swelling, prolonged intubation, velopharyngeal insufficiency, dysphagia, and dysphonia.

We present a case of a 66-year-old man with no pertinent past medical history, who presented with progressive quadriparesis and gait ataxia over last 6 months (Nurick's grade 2). Neurological exam revealed pattern suggestive of high-cervical myelopathy with no evidence of cranial nerve paresis. Magnetic resonance imaging (MRI) of his CVJ revealed a large pannus behind the dens with severe spinal cord compression, mild contrast enhancement was noted posterior to the pannus, likely from the ligamentous structures; pannus was hypointense on both T1- and T2-weighted images. Further, a computerized tomography (CT) scan did not reveal any obvious malalignment. He underwent an EE odontoidectomy, followed by posterior cervical fusion. He had an unremarkable postoperative period and recovered fully from his myelopathy over the next 6 months. The histopathological examination of the pannus revealed a degenerated disk. In this video, we have a step by step description of the EE approach to the odontoid and discuss the surgical nuances.

The link to the video can be found at: https://youtu.be/pjg68_vK0C4.
Motion Preserving Surgery Using O-Arm for Unstable Hangman Fracture
Authors: Verma Satish Kumar , Singh Pankaj Kumar , Sawarkar Dattaraj Parmanand , Kumar Amandeep , Agarwal Deepak , Chandra P. Sarat , Kale Shashank Sharad
Published: October 2019

Aim To evaluate clinical outcomes, radiological findings (displacement and angulation), and bony fusion in cases of unstable hangman’s fracture.

Introduction Hangman fracture, also known as traumatic spondylolisthesis of axis vertebra, is classically defined as bilateral pars interarticularis fracture of axis vertebra. Opinions vary regarding optimal treatment of unstable hangman’s fractures. Some authors have recommended use of rigid orthosis, whereas others have recommended internal fixation. The peculiar anatomy of the upper cervical spine is highly variable, and presence of surrounding neurovascular structures makes axis pedicle screw fixation even more technically challenging. The advent of intraoperative three-dimensional navigation systems facilitates safe and accurate instrumentation.

Materials and Methods This article analyzes patients operated for type II and IIa hangman’s fractures during the period from September 2011 to August 2018 by two neurosurgeons. The patients’ age, sex, mechanism of injury, associated injuries, and neurologic status were noted. The authors retrospectively assessed the clinical outcome, radiological findings (displacement and angulation), and bony fusion.

Result Eighteen patients with age ranging from 17 to 81 years, were operated using computed tomography-based (O-arm) navigation. Accuracy of screw insertion, preoperative and postoperative displacement, and angulation of C2 over C3 were evaluated. Bony fusion was assessed in all patients. A total of 92 screws were inserted: 36 screws in C2 pedicle, 34 in C3 lateral mass, 20 in C4 lateral mass, and 2 in C5 lateral mass. Of these 92 screws, 36 C2 pedicle screws were inserted under O-arm guidance. The mean preoperative C2–C3 displacement was 4.5 ± 2.1 mm, and the mean postoperative displacement was 1.8 ± 1.1 mm with a mean reduction of 2.7 ± 1.4 mm. The mean preoperative C2–C3 angulation was 10.2 ± 7.6 degrees and the postoperative angulation was 2.52 ± 4.62 degrees with a mean reduction of 8.2 ± 11.6 degrees. Screw malplacement was seen in two C2 pedicle screws (2/36, 5.5%). All C2 pedicle screw breaches were of grade 2. Excellent anatomical reduction in all cases could be achieved as established by the improvement in morphological parameters of fracture.

Conclusion This series using O-arm in unstable hangman fracture demonstrates that intraoperative O-arm-based navigation is a safe, accurate, and effective tool for screw placement in patients with unstable hangman fracture.
Simulations for InAlAs digital alloy avalanche photodiodes
Authors: Zheng J. , Yuan Y. , Tan Y. , Peng Y. , Rockwell A. , Bank S. R. , Ghosh A. W. , Campbell J. C.
Published: October 2019

3D band structure-based Monte Carlo simulations have been utilized to simulate InAlAs digital alloy avalanche photodiodes. The simulated current–voltage curve and excess noise factor fit well with experimental results. Ionization coefficients calculated by the Monte Carlo technique were incorporated into the recurrence model, which is easier to implement and requires less computation time.
A non-invasive microcontroller based estimation of blood glucose
concentration by using a modified capacitive sensor at low
frequency
Authors: Dutta Abhinaba , Chandra Bera Satish , Das Kamalesh
Published: October 2019

In the present work, a noninvasive technique of glucose concentration measurement in human blood has been developed. A semicylindrical capacitive sensor is used to measure the blood glucose concentration in terms of capacitance of the sensor. It is shown that this capacitance varies linearly with glucose concentration in human blood. A low frequency operational amplifier based circuit is designed to measure this capacitance in terms of an output voltage signal. A linear relation between the ratio of this output signal to input supply with blood glucose concentration is derived in the paper. A microcontroller based software program is designed to measure this ratio and to display glucose concentration in a LCD display unit in digital form. The performance study of the proposed blood glucose concentration measurement circuit with respect to standard glucometer and that of the proposed blood glucose concentration display unit are carried out in the present work. The experimental results are reported in the paper in both tabular and graphical forms. The linear characteristic graphs and close conformity of the results of the proposed technique with those of standard glucometer are observed. The measurement error with respect to glucometer is found to be within ±3.5%.
High-energy radiation and pair production by Coulomb processes in particle-in-cell simulations
Authors: Martinez B. , Lobet M. , Duclous R. , d'Humières E. , Gremillet L.
Published: October 2019

We present a Monte Carlo implementation of Bremsstrahlung, Bethe-Heitler, and Coulomb Trident processes into the particle-in-cell (PIC) simulation framework. In order to address photon emission and electron-positron pair productions in a wide range of physical conditions, we derive the Bremsstrahlung and Bethe-Heitler cross sections taking account of screening effects in arbitrary ionized plasmas. Our calculations are based on a simple model for the atomic Coulomb potential that describes shielding due to both bound electrons, free electrons, and ions. We then detail a pairwise particle interaction algorithm suited to weighted PIC plasma simulations, for which we perform several validation tests. Finally, we carry out a parametric study of photon and pair production during high-energy electron transport through micrometric solid foils. Compared to the zero-dimensional model of Myatt et al. [Phys. Rev. E 76, 066409 (2009)], our integrated one-dimensional simulations pinpoint the importance of the electron energy losses resulting from the plasma expansion.
Long-range dispersal promotes species persistence in climate extremes
Authors: Narang Arzoo , Bhandary Subhendu , Kaur Taranjot , Gupta Anubhav , Banerjee Tanmoy , Dutta Partha Sharathi
Published: October 2019

Anthropogenic global warming in this century can act as a leading factor for large scale species extinctions in the near future. Species, in order to survive, need to develop dispersal strategies depending upon their environmental niche. Based on empirical evidence only a few previous studies have addressed how dispersal can evolve with changing temperature. However, for the analytical tractability, there is a need to develop an explicit model to ask how the temperature-dependent dispersal alters ecological dynamics. We investigate the persistence of species in a spatial ecological model, where dispersal is considered as a function of temperature. Spatial persistence is of major concern and dispersal is reasonably an important factor for extinction risk in the context of promoting synchrony. Our study yields how the temperature influences species decision of dispersal, resulting in either short-range or long-range dispersal. We examine synchronous or asynchronous behavior of species under their thermal dependence of dispersal. Moreover, we also analyze the transients to study the collective behavior of species away from their final or asymptotic dynamics. One of the key findings is at the most unfavorable environmental conditions long-range dispersal works out as the driving force for the persistence of species.
Electromagnetic noise of a nanosecond magnetized high-current electron beam
Authors: Shunailov S. A. , Mesyats G. A. , Romanchenko I. V. , Rostov V. V. , Sadykova A. G. , Sharypov K. A. , Shpak V. G. , Ulmasculov M. R. , Yalandin M. I.
Published: October 2019

We present an analysis of the characteristics of the noise from a magnetized high-current electron beam at a nanosecond-long interval since the explosive electron emission onset on the graphite cathode by applying accelerating pulses with an amplitude of about −300 kV and a varying subnanosecond rise time. The registration bandwidth of electromagnetic noise and the beam current modulation was as high as 59 GHz. A leading wideband electromagnetic signal linked with a short beam current front was recorded. Subsequent noise, including that with discriminated spectral maxima, can be qualified as spontaneous cyclotron radiation of moderately relativistic electrons rotating in a longitudinal magnetic field.
Kinking effects and transport properties of coaxial BN-C nanotubes as revealed by in situ transmission electron microscopy and theoretical analysis
Authors: Zhou Xin , Kvashnin Dmitry G. , Xue Yanming , Tang Dai-Ming , Cretu Ovidiu , Mitome Masanori , Bando Yoshio , Sorokin Pavel B. , Sasaki Takayoshi , Golberg Dmitri
Published: October 2019

The insights into transport behavior and the effects of bending on heterostructures constructed from boron nitride (BN) and carbon (C) nanotubes are important for their flexible device applications because the two systems have equally excellent mechanical but completely different electrical properties. In this work, coaxial BN–C nanotubes have been fabricated and their intrinsic transport properties, as well as structural and electrical response to bending deformation, are studied inside a high-resolution transmission electron microscope. Ballistic, diffusive, and hopping transports within different tube length ranges have been observed. When bending deformation was applied to the tubes, although severe kinking becomes apparent, their transport properties are not notably affected. Meanwhile, both theoretical and experimental analyses confirm that the kink positions depend on the ratio of tube diameter to its length. Possible formation of quantum dots, directly within the kink areas, was predicted through calculations of electron density redistribution between nanotube walls at bending.
What ecological role do soft-substrate tide pools play for fishes? Difference in community structures between estuarine and coastal tidal flats in subtropical Japan
Authors: Kunishima Taiga , Tachihara Katsunori
Published: October 2019

Soft-substrate tide pools are considered important habitats for fishes from an ecological perspective. However, the ecological roles of such pools and use patterns by fish remain unclear, especially regarding differences between estuarine and coastal tidal flats. In this study, quantitative sampling using the quadrat method was performed in the estuarine and coastal tidal flats on Okinawa-jima Island of subtropical Japan during four seasons. Ecological roles of soft-substrate tide pools were classified as follows: (1) permanent habitat for residents; (2) nursery ground for transients; and (3) waiting area until high tide for accidental species. Within these classifications, the ecological role and value of tide pools for transient fishes varied between the tidal flat types. The habitat value of tide pools is higher for residents than for transient species because the habitat is not replaceable for residents because of their specific ability to survive there. By contrast, transient and accidental species use the tide pools as temporary habitats; however, their high diversity affects the variation in community structure on Okinawa-jima Island. Our results suggest that we should consider not only species diversity, but also habitat use patterns of individual species, together with their life history, when evaluating habitat value with regard to conservation and management of each tidal flat.
Exploration of the Association of Selected Pain Diagnoses with Risky Alcohol use among Active Duty Soldiers
Authors: Reif Sharon , Adams Rachel Sayko , Ritter Grant A. , Larson Mary Jo
Published: October 2019

Background

Pain and its consequences remain of concern, particularly in high-risk occupations such as the military. Alcohol is a legal and accessible means of self-medication, and risky alcohol use is associated with potentially serious consequences. This exploratory analysis aimed to better understand the association of selected pain diagnoses with risky alcohol use among soldiers returning from deployment.

Methods

Analysis of data from active duty soldiers returning from Afghanistan or Iraq deployments in fiscal years 2008–2011 who completed Department of Defense health questionnaires after deployment ( n = 267,100). Each questionnaire included self-reported alcohol consumption and items yielding AUDIT-C screening scores. Military Health System data were used to identify diagnoses of pain-related conditions.

Results

About 70% of soldiers had none of the selected pain diagnoses either pre- or post-deployment. 10% had incident pain diagnoses (only post-deployment), 7% had persistent pain diagnoses (both pre- and post-deployment), and 13% had remitted pain diagnoses (only pre-deployment). On the AUDIT-C, 39% screened positive for at-risk drinking and 6% were likely to have severe alcohol problems. Half of the respondents reported any binge drinking; 20% at least monthly binge drinking. Logistic regression analyses found reduced odds of risky alcohol use post-deployment in association with incident and persistent pain diagnoses, compared to no pain diagnoses pre- or post-deployment.

Conclusions

Pain diagnoses, binge drinking, and risky alcohol use were prevalent among this sample of Army soldiers. An inverse relationship was found between pain diagnosis (incident, persistent) and risky alcohol use post-deployment. Attention should continue to be paid to risky alcohol use in this population, yet these exploratory findings do not suggest that soldiers with the pain diagnoses used in this study are at greater risk. Combat exposure, traumatic brain injury, and psychological health were more important predictors, and should continue to warrant enhanced alcohol screening.
Article Commentary: Nursing: Addressing Substance use in the 21st Century
Authors: Finnell Deborah S. , Tierney Matt , Mitchell Ann M.
Published: October 2019

Over the past two decades, there has shift from focusing on the most severe end of the substance use continuum to earlier detection of persons who are at risk given the consequences associated with alcohol and other drug use. In 2017, the Association for Multidisciplinary Education and Research in Substance Use and Addiction (AMERSA) undertook the development of core competencies for specific disciplines addressing substance use in the 21st century. This article presents the core competencies for nursing in accord with the 16 standards of practice and performance for nursing. The competencies for the registered nurse and the advanced practice nurse are intended to inform and guide nursing practice with a focus on prevention, intervention, treatment, and recovery supports for persons who are affected by substance.
Kazuhiro Maeshima: Excitement under the microscope
Authors: O’Donnell Marie Anne
Published: October 2019

Maeshima investigates the higher order structures and dynamics of chromatin.
Drift effects on W7-X divertor heat and particle fluxes
Authors: Hammond K C , Gao Y , Jakubowski M , Killer C , Niemann H , Rudischhauser L , Ali A , Andreeva T , Blackwell B D , Brunner K J , Cannas B , Drewelow P , Drews P , Endler M , Feng Y , Geiger J , Grulke O , Knauer J , Klose S , Lazerson S , Otte M , Pisano F , Neuner U , Sitjes A Puig , Rahbarnia K , Schilling J , Thomsen H , Wurden G A
Published: October 2019

Classical particle drifts are known to have substantial impacts on fluxes of particles and heat through the edge plasmas in both tokamaks and stellarators. Here we present results from the first dedicated investigation of drift effects in the W7-X stellarator. By comparing similar plasma discharges conducted with a forward- and reverse-directed magnetic field, the impacts of drifts could be isolated through the observation of up-down asymmetries in flux profiles on the divertor targets. In low-density plasmas, the radial locations of the strike lines (i.e. peaks in the target heat flux profiles) exhibited discrepancies of up to 3 cm that reversed upon magnetic field reversal. In addition, asymmetric heat loads were observed in regions of the target that are shadowed by other targets from parallel flux from the core plasma. A comparison of these asymmetric features with the footprints of key topological regions of the edge magnetic field on the divertor suggests that the main driver of the asymmetries at low density is poloidal E × B drift due to radial electric fields in the scrape-off layer and private flux region. In higher-density plasmas, upper and lower targets collected non-ambipolar currents with opposite signs that also inverted upon field reversal. Overall, in these experiments, almost all up-down asymmetry could be attributed to the field reversal and, therefore, field-dependent drifts.
A holistic approach to natural ventilation studies
Authors: Liu Sumei , Chen Qingyan
Published: October 2019

Natural ventilation in buildings can increase thermal comfort and reduce air-conditioning use. However, it is very challenging today to accurately determine the natural ventilation rate through a building. This paper outlines a method to calculate the wind distribution around a building site from information obtained at a meteorological station miles away. This paper also discusses the influence of surrounding buildings on the wind flow around a target building at the site, and presents various geometrical models. In addition, the use of hour-by-hour wind velocity typically available from a meteorological station may give rise to some errors because of the large time step. A correlation method can be employed to convert the hour-by-hour wind velocity to minute-by-minute velocity. One can then use CFD to calculate the airflow around the building and wind-driven cross ventilation through an apartment simultaneously. However, prediction of single-sided natural ventilation is difficult because of the bi-directional flow at the room opening and the complex flow around buildings. This paper presents an empirical model that can predict the mean and fluctuating ventilation rates due to the pulsating flow and eddy penetration of wind-driven single-sided ventilation in buildings with three types of windows. One must use the correct strategy in a building in order to achieve the maximum benefits of natural ventilation.
A test bed for thermal fluid dynamic analysis of double skin facade systems
Authors: Jankovic A , Goia F , Eckert D , Müller P
Published: October 2019

The experimental analysis of the thermal fluid dynamic behavior of double skin facade (DSF) requires full scale prototypes or actual facade systems. Because of the crucial interaction with the solar irradiation, tests are usually carried out on facades that are outdoor exposed. However, such an approach has limitation when it comes to a systematic and parametric analysis of the performance of these technologies, as the (outdoor) boundary conditions can hardly be controlled. To overcome this limitation, a new test bed has been conceived and constructed to allow carrying out systematic and parametric analysis on DSF systems. The test bed is a full scale DSF, with the possibility to vary the cavity depths from a minimum value of 200 mm to a maximum value of 600 mm. The total height of the DSF sample is ca 3.6 m, with a transparent window area of approx. 1.4 m (W) x 2.8 m (H). The test bed is installed in a steel frame and is tested through a Climate Simulator facility (a hot-box like facility, with the possibility to irradiate the outside surface of the test sample through a solar simulator). In the paper, the concept of the test bed, the construction features, and its sensor/control set-up are presented, together with an overview of its potentials (and limitations) to carry out experimental analysis on the thermal fluid dynamic behavior of DSF systems.
Practicability and reliability of direct component testing for in-situ measurement of building component airtightness
Authors: Prignon M , Dawans A , Van Moeseke G
Published: October 2019

Airtightness at building component scale deserves much more focus than it gets. Unfortunately, the most popular method (i.e., indirect method) for its in-situ measurement suffers from substantial uncertainties. An alternative method is the direct component testing: a pressure chamber isolates the component from the rest of the building. This paper presents the method performed on three different newly-installed windows. These applications highlight three difficulties encountered: the chamber must resist to pressure differences higher than 50 Pa, the duct linking the fan to the chamber should be straight and the measured leakage should be perfectly identified. Then, authors performed two series of tests (10 and 12) in repeatability conditions. These allow to compare the uncertainty of the direct component testing (0.29 m3/h, 9.7%) with the expected uncertainty of the indirect method for a similar case (1.53 m3/h, 51.2%). These findings indicate a strong potential for the direct component testing to be used for in-situ measurements. Further work should tackle three limitations of this study identified by authors: other building component should be tested; other repeatability tests should be performed to identify factors responsible for the results variation; and both methods (i.e., direct and indirect) should be compared on the same case.
A parametric design method for CFD-supported wind-driven ventilation
Authors: Merin Abbas Günsu , Gürsel Dino İpek
Published: October 2019

The negative impact of the building industry has brought a critical emphasis on the performance-related tools and processes of architectural design. The integration of design and performance simulation has the potential to extend the decision-making capabilities of the architects. Amongst a number of performance parameters, wind-related measures are generally problematic for the design phase, due to the computational cost of predicting wind behaviour, the complexity of the urban context and the constantly changing airflow patterns. In this respect, this paper proposes the preliminary exploration of a design method towards integrating Computational Fluid Dynamics (CFD) coupled with energy modelling and parametric design tools for the wind-related design acts. As building performance is regarded as a design problem that necessitates a designerly point of view as much as a technical perspective, the method aims at providing visual, generative and accurate feedback regarding its potential to facilitate the architect’s designerly integration to the process and to provide a flexible design environment. The preliminary quantitative analysis conducted through a case study indicates the preliminary data flow through the design process.
Active living wall modules - CO2 and CH2O purification
Authors: Hung Yi-Hsuan , Chen Jia-Kun , Yeh Der-Ming , Tseng Tzu-I
Published: October 2019

Today, our green walls help to alleviate urban heat island effects, reduce noise and improve air quality. However, this design can be found to be detrimental to airflow and it does not use air to improve air now. Therefore, we must consider the characteristics of the factory and the correct principle of fluid mechanics design. The air can flow through the green wall by inhalation to achieve the function of beautifying and purifying the air. And we will put active living wall module indoors, because many studies have shown that people spends to 80% to 90% of the time to stay indoor. Researchers believe that indoor air quality is closely related to people’s health. It also meets WELL building standards. And there are also studies that indicate that plants in the classroom can increase the attention of school children. Therefore, the purpose of this study is to use fluid mechanics to design a new green wall for air purification and beautify the environment and promote air quality to create a better living environment. This study placed the active living wall module and the wooden core board together in a transparent acrylic box. After the veneer volatilizes volatile organic substances such as formaldehyde, the module is activated to cause the volatilized gas to pass through the pores below the leaves of the plant as the gas flows. It is also measured whether the concentration of the organic substance before and after passing is effectively changed after passing through the plant. At the same time, the relationship between the wind speed and the stomata of Baihejing is obtained experimentally, and the best photosynthesis efficiency can be obtained. This study found that the pumping mode removed 33% more formaldehyde than the non-exhausted mode. For this study, when 10.5 V (0.6 m/s) is given, there is an optimum photosynthesis efficiency between the wind speed and the planting pores, so the test will be tested at 0.6 m/s. We have found that active living wall module achieve increased efficiency in reducing pollutants. There is another experiment in this study to compare the active living wall modules with the commercially available air purifier. We evaluated the purification of formaldehyde and carbon dioxide, and the price and energy consumption etc. We found that this active living wall modules and commercial air purifier have the same ability of purification. However, there are still many issues in this research that have not been discussed in the future, so it will be more in-depth experiments and research, and also to develop a with the technology of low energy consumption, low pollution, low cost and good aesthetics, the active living wall module goal of reducing indoor air pollution is advanced.
Assessment of an experimental method for determining the three key parameters of VOC emissions from solid materials
Authors: Caron Florent , Guichard Romain , Robert Laurence , Verriele Marie , Thevenet Frédéric
Published: October 2019

The VOC emission processes from a solid material can be described by three key parameters: the partition coefficient (K), the initial emittable concentration (C0) and, the diffusion coefficient (D). These emission key parameters need to be determined experimentally for a VOC-material pair. A new method from literature allows determining simultaneously the three emission key parameters. However, this method has been evaluated in a single experiment only for formaldehyde. Therefore, the purpose of this study is to assess the efficiency and the reproducibility of the experimental method from literature performing three tests in the same experimental conditions. This work permits to determine the three key parameters of eight main VOC emitted from a particleboard and to evaluate the accuracy of the experimental method. Successfully, experiments carried out using a 128 L well-mixed chamber containing a particleboard, and connected to an online gas analyzer (Selected Ion Flow Tube-Mass Spectrometry), allow the effective characterization of the source material. Results evidence that compared to other VOCs, formaldehyde shows a specific behaviour: the response of formaldehyde between airtight and ventilated regimes is highly contrasted with those of other emitted VOCs.
Beyond recovery: measuring ventilation strategies and their impact on energy
Authors: Bakshi N , Donn M R , Ganda Sanjeev , Wallace J
Published: October 2019

Working with a medium scale, research-focused architectural practice this paper measures the efficacy of balanced pressure heat recovery ventilation systems (BPHR systems) in the existing housing stock as a strategy to mitigate thermal heat loss when incorporating ventilation strategies in New Zealand. Current research indicates that BPHR systems boast an efficiency upwards of 80%. The aim of this research is to determine at what point do BPHR systems meet current claims of efficiency. An examination of the existing New Zealand housing stock identifies that 66% of all dwellings do not meet thermal performance requirements. This has been attributed, in part, to the governance of legislation of minimum performance, which did not exist until 1978. This paper, first, identifies building simulation measures and assumptions to accurately simulate BPHR systems in controlled conditions, which is quality assured against the expected performance of a conventional code minimum residential building and a range of models that represent a spectrum of building leakage for pre-legislation buildings. This paper then examines passive ventilation strategies in each model to identify the energy balance of using BPHR systems and the potential for heating energy loss when implementing simpler ventilation strategies. This study identifies that the efficiency of BPHR systems significantly differ in the pre-legislation building simulations. In these models, the building leakage alone renders heat recovery negligible in comparison to simple passive design and occupant-controlled measures thatm achieve a similar result for the indoor air quality.
Effects of gender on thermal comfort of stratum ventilation with pulsating air supply
Authors: Li Yunhao , Tian Xue , Liao Chunhui , Cheng Yong
Published: October 2019

Physiological and psychological differences between males and females can lead to differences on thermal comfort. A novel ventilation strategy, stratum ventilation with pulsating air supply, have potentials to improve thermal comfort in warm conditions. Experiments were conducted in a classroom mock-up with dimensions of 8.4 m (L)×5.4 m (W)×2.6 m (H) served by stratum ventilation with pulsating air supply. There are two rows, and each row can hold six occupants. Twenty-five healthy subjects (i.e., 10 males and 15 females, aged 21-36 years) were recruited to attend the experiments. All the subjects were exposed to four test conditions with different combinations of supply air temperatures, air velocities and/or periodic time. Subjects’ perceptions on thermal comfort, thermal sensation and draft perception were obtained via the questionnaires. The longer cycle time will eliminate the difference on thermal sensation between genders. The difference on draft sensation disappeared at high velocity. Males show good tolerance to thermal environment. For all the cases, more than 80% of subjects voted thermal comfort as comfortable which shows that the thermal environments produced by stratum ventilation with pulsating air supply were acceptable.
Risk for contamination in a cleanroom with weakened aerodynamic barrier
Authors: Lind Knudsen Lasse , Georgiev Naydenov Kiril , Rasmussen Carsten , Krikor Melikov Arsen , Fang Lei
Published: October 2019

The risk for contamination in a pharmaceutical cleanroom was investigated through tracer gas measurements in 13 different scenarios, when the aerodynamic barrier between an airlock (AL) and a cleanroom (CR) was weakened by opening the door separating the rooms. Air velocities through the doorway, differential temperature between the airlock and the cleanroom, different door opening speeds and different walking paces of a mannequin entering the cleanroom were the four parameters in focus. The study was conducted in a full-scale cleanroom mock-up (4.7 x 3.5 x 2.5 m), where each scenario was repeated three times. The results of the investigation show that air velocity through the doorway is the most important design parameter to ensure the aerodynamic barrier, when an average air velocity between 0.14 m/s (resulted in 209 l of migrated air) and 0.33 m/s (resulted in 62 l of migrated air), which was achieved at isothermal conditions and with a door opening time of 10 seconds. Increasing the door opening time to 20 seconds diminishes the effect of a higher air velocity to neglectable levels. Last by not least, the differential temperature between airlock and cleanroom has an impact on the air migration, where a warm cleanroom (24 °C) and a cold airlock (20 °C) showed a low contamination risk with a door opening time of 10 seconds. A warm cleanroom (24 °C) and a cold airlock (20 °C) showed on the other hand a high level of air migration with almost 1.500 l of contaminated air entering the clean zone with a door opening of time 10 seconds.
Comparative analysis of thermal environment between raised-floor and row-based cooling in a campus data center
Authors: Jin Chaoqiang , Bai Xuelian , An Ya’nan , Zhang Xin
Published: October 2019

In recent years, the modular data center, which adopts row-based cooling strategy, is becoming popular and widely applied. Also, cold aisle containment is integrated to reduce the mixing of hot and cold air. Even so, similar to the raised-floor cooling, the cold air bypass and hot air recirculation still affect the thermal environment. This paper presents the comparison of thermal environment between raised-floor and row-based cooling, through changing the factors of servers’ arrangement, aisle containment and blanking panel. Experiment and simulation were employed to investigate the inlet air temperature of racks and thermal environment of the data room, and a total of 15 models were simulated. The results showed that combining the cold aisle containment with blanking panels can bring uniform airflow, and the servers installed in the upper part of the rack was the best choice for the both cooling strategies. Especially, the blanking panels could further improve the airflow for all servers’ arrangement using row-based cooling strategy, which can reduce the mean inlet air temperature by 16.7 °C, and the minimum SHI value can reach to 0.089. These results could guide the thermal environment management to guarantee the effective utilization of cooling capacity in data centers.
Improving the Energy Performance Certificate recommendations accuracy for residential building through simple measurements of key inputs
Authors: Gonzalez-Caceres A , Vik T A
Published: October 2019

The Energy Performance Certificate (EPC) allows building users to be informed and aware of the quality of the buildings in terms of energy needs. Additionally, the EPC includes a future for existing buildings, which is the incorporation of a Recommendation list of Measures (RLMs) to improve their energy performance in a cost-effective way. This has risen the question if this tool can provide trustful cost-effective recommendations due despite the use of standardized inputs. This study focuses on estimating the impact of using measured ventilation rate, heating set point and airtightness on the profitability of the recommendations. The study is based on a common dwelling in Norway, comparing results obtained with a Building Performance Simulation Software, following the Norwegian standard for energy certification and with the use of measured ventilation rate, airtightness and real heating set points. The results show that the performance gap can be reduced significantly just by adopting these inputs, increasing the confidence on the RLMs and reducing the uncertainty of the investment.
Long-term performance of fibrous ventilation/air cleaner filter for particle removal
Authors: Ji Lili , Pei Jingjing , Liu Wenlong
Published: October 2019

The performance of building ventilation systems and/or portable indoor air cleaners is greatly affected by the performance of the fibrous filters installed in them. The initial particle efficiency is generally used as a measure to evaluate the performance of the fibrous filters. However, with dust loading, the long-term performance of the filters might change, and the filters may become particle sources themselves and affect the performance of other systems. Previous studies on long-term performance were mainly based on theoretical analyses or laboratory experimental tests. This study investigates the long-term efficiency and pressure-drop change of various ventilation filters during real operation. No obvious efficiency decrease is observed, and it is inferred that the effect of dust loading on efficiency can be ignored. Secondary particle detachment is found to be possible in real applications, but its effect on the downstream concentration and indoor air can be made negligible with the use of an H-level filter. The pressure drop of the ventilation filter is also found to increase significantly.