bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional impairment of blood-brain barrier following pesticide exposure during early development in rats
Authors: Gupta Alka , Agarwal Renu , Shukla Girja S 
Published: January 2017

1 The effect of certain pesticides on the functional integrity of the developing blood-brain barrier (BBB) was studied following single and repeated exposure, and after subsequent withdrawal in rats. 2 Ten-day-old rat pups exposed orally to quinalphos (QP, organophosphate), cypermethrin (CM, pyre-throid) and lindane (LD, organochlorine) at a dose of 1/50th of LD50, showed a significant increase in the brain uptake index (BUI) for a micromolecular tracer, sodium fluorescein (SF), by 97, 37 and 72%, respectively, after 2 h. Residual increases in the BUI were found even after 3 days of the single treatment of QP (28%) and LD (23%). 3 Repeated exposure for 8 days (postnatal days (PND) 10-17) with QP, CM and LD increased the BBB permeability by 130, 80 and 50%, respectively. Recovery from these changes was complete in QP and LD-treated animals after 13 days (PND 18-30) of withdrawal. However, CM showed persistent effects that were normalized only after 43 days (PND 18-60) of withdrawal. 4 A single dose reduced to 1/100th of LD50 also increased BUI in 10-day-old rat pups following QP (20%) and CM (28%) exposure at 2 h. 5 An age-dependent effect of these pesticides was evident from the study showing higher magnitude of BUI changes in 10-day-old rats as compared to that in 15- day-old rats. Furthermore, adult rats did not show any effect on BBB permeability even at a higher dose (1/25th of LD50) of these pesticides given alone or in combination with piperonyl butoxide (600 mg/kg, i.p.) for 3 consecutive days. 6 This study showed that developing BBB is highly vulnerable to single or repeated exposure of certain pesticides. The observed persistent effects during brain development even after withdrawal of the treatment may produce some neurological dysfunction at later life as well.
Uncovering the effects of smoking: historical perspective
Authors: Doll Richard 
Published: January 2017

Tobacco was introduced into Europe from America at the end of the fifteenth century. At first used primarily for medicinal purposes it came to be burnt in pipes for pleasure on a large scale nearly 100 years later, at first in England and subsequently in Europe and throughout the world. Pipe smoking gave way to the use of tobacco as snuff and, in turn, to cigars and cigarettes at different times in different countries until cigarette smoking became the dominant form in most of the developed world between the two world wars. Societies were formed to discourage smoking at the beginning of the century in several countries, but they had little success except in Germany where they were officially supported by the government after the Nazis seized power. In retrospect it can now be seen that medical evidence of the harm done by smoking has been accumulating for 200 years, at first in relation to cancers of the lip and mouth, and then in relation to vascular disease and cancer of the lung. The evidence was generally ignored until five case-control studies relating smoking to the development of lung cancer were published in 1950. These stimulated much research, including the conduct of cohort studies, which, by the late 1950s, were beginning to show that smoking was associated with the development of many other diseases as well. The interpretation that smoking caused these various diseases was vigorously debated for some years but came to be generally accepted in respect of lung cancer by the late 1950s and of many other diseases in the subsequent two decades. Cigarette smoking has now been found to be positively associated with nearly 40 diseases or causes of death and to be negatively associated with eight or nine more. In some instances the positive associations are largely or wholly due to confounding, but the great majority have been shown to be causal in character. The few diseases negatively associated with smoking are for the most part rare or nonfatal and their impact on disease incidence and mortality as a result of smoking is less than 1% of the excess of other diseases that are caused by smoking. The most recent observations show that continued cigarette smoking throughout adult life doubles age-specific mortality rates, nearly trebling them in late middle age. All the diseases related to smoking that cause large numbers of deaths should now have been discovered, but further nonfatal diseases may remain to be revealed by cohort studies that are able to link individuals' morbidity data with their personal characteristics.
On the Acoustics of Auditoria
Authors: Kuttruff H. 
Published: January 2017

The paper presents a short introduction into auditorium acoustics and reports on a few new developments in this field, which are believed to be of great benefit both for the acoustical design of auditoria and for research in practical room acoustics. The first part describes in a rather elementary way the basic facts of sound propagation in enclosures, including the effects of reflections and the role of reverberation. Furthermore, some of the numerous objective parameters are discussed which have been introduced in order to characterize particular aspects of sound fields. In the second part, recently developed methods of sound field simulation are described by which such parameters can be predicted. Methods of “auralization” are briefly discussed by which aural impressions from non-existing halls can be created on the basis of digital sound field simulation.
Computer Prediction of Insertion Loss Due to a Single Barrier in a Non-Diffuse Empty Enclosed Space
Authors: Dance S.M. , Roberts J.P. , Shield B.M. 
Published: January 2017

This paper describes the development of an efficient barrier model for the prediction of sound distribution in non-diffuse empty enclosed spaces. Diffraction is modelled using an extended version of the Ondet and Barbry computer model, RAYCUB, which is a proven model used to predict sound distribution in empty and fitted non-diffuse enclosed spaces. As RAYCUB is based on geometric acoustics, it is not possible to directly model diffraction around a barrier. Diffraction around barriers is known to cause only localised, frequency dependent effects on sound distribution in acoustically complex environments such as factories. It was intended that a barrier model should impose a minimum of additional computation time on the factory noise prediction program. Three methods of approximating barriers were developed, all based upon a simplified implementation of the geometric theory of diffraction. The barrier models were tested in two configurations of an empty test space. The model REDIR gave more accurate results than the original RAYCUB model, especially at lower frequencies.
The Development of Computer Models for the Prediction of Factory Noise
Authors: Dance S.M. 
Published: January 2017

The development of factory noise prediction models over the past thirty years has parallelled the development of computer technology. There are currently two main approaches to this problem both of which have been extensively investigated, they are the image-source method and the ray-tracing technique. Presented are brief details of the background to the specific problems of factory noise prediction together with the various approaches used to solve the problem. An outline of how the two types of mathematical models work, together with details of their representational development is presented. A comparison of the current potential of each type of model, enabling an insight into when and where each type of model may be effectively used, is given. Three independent studies comparing various prediction models were considered. All three reviews drew the conclusion that the Ondet and Barbry, and the Lindqvist models were the most accurate ray-tracing and image-source models, respectively. Finally, a review of barrier prediction models is presented.
Impulse Response Analysis: An Alternative Method of Measuring Sound Insulation
Authors: Lyons R. , Gibbs B.M. 
Published: January 2017

This paper investigates the use of Impulse Response Analysis methods for measuring sound insulation, in particular for elements which provide low sound insulation, such as thin panels, barriers and open screens, where standard methods are inappropriate. A practical explanation of Impulse Response Analysis and its application is given, indicating, through studies on single panels as partitions and as screens, that such elements are amenable to this method of measurement. Explanation of time history components and problems of signal capture are provided together with validation of the results by comparison with classical theory and, for screens, prediction taken from optical diffraction theory. Generally, agreement with theory is good and it is shown that the normal incidence impulse response data can be used with known empirical expressions to obtain the diffuse field transmission loss, so providing an indication of the expected performance in test laboratories and the field.
Prediction of Sound Level in Rooms and Experimental Validation
Authors: de Souza Mauricy Cesar R. , Gerges Samir N.Y. 
Published: January 2017

Traditional Sabine equations still are used for factories or offices where diffuse sound fields rarely occur and prediction can be inaccurate. More recently, methods based on geometric acoustics have been developed which require large computing time and which demand better defined input data. A problem, often encountered, is how to include input data which is appropriate, accurate and relatively easy to obtain. Three acoustic models of a furnished room were created: a diffuse field, an image source and a ray tracing model. The initial values of absorption coefficient and sound power level were obtained by standard measurements and the sound propagation SP was predicted and compared with measurement for each model. Then, the models were calibrated by altering the input parameters in order to minimise the difference between predicted and measured values. Sound pressure level due to two sources was also predicted and compared with measurement. For the room studied, the precision of the predictions, after calibration, is similar for the three models considered, with an average difference between simulated and measured values of less than 2 dB. Without the calibration procedure, the ray-tracing model gave the most precise first estimate. The diffuse and image source models needed significant modification of the input data to obtain a similar precision. The sound field in the room chosen for this study was nearly diffuse and simulation, based on geometric acoustics, did not offer clear advantages. However, this will not be the case for rooms with more complicated geometrical and acoustic characteristics such as in factories and offices. In addition, the image source model will not be appropriate for internal fittings which are much more complex than in the present study and an appropriate estimate of the scattering cross-section is problematical. In the ray tracing model, this problem is circumvented by incorporating the fittings as part of the geometry of the room.
The Influence of Concrete Elastic Characteristics on the Impact Noise Insulation of Concrete Floors
Authors: Patrício Jorge , Silva P. Martins da , Piedade A. Canha da 
Published: January 2017

The noise insulation characterisation of a bare floor for structure-borne sound is usually based on specific tests made in accordance with the established international standard EN ISO 20140 and the structure-borne noise insulation index calculated according to standard EN ISO 20717. For bare concrete floors of the same type, which one might suppose would have identical acoustical performance, different impact sound insulation frequency spectra may be obtained if the concrete at the zone where the impact hammer strikes is of different type. This situation is particularly the case for bare floors which have levelling layers of floor screeds. This work presents an analytical study of the influence of the elastic characteristics of the concrete used in the area of the bare floor where the hammer of the standard tapping machine strikes (whether it be the structural concrete of the slab or a light concrete screed applied as a levelling layer), on the impact noise insulation spectra, and on the corresponding value of the structure-borne sound insulation index. The study firstly involved theoretically modelling the applied impulsive force spectrum of the hammer impact. Secondly, the modelled force spectrum was compared with the results of impact characteristics obtained using several shock tests on defined specimens, for which the effective impact force is determined. Finally, using these resulting force spectra, some simulations on a standard floor were performed to determine the changes in the response spectra, and the corresponding insulation index for structure-borne sound. Some additional considerations and conclusions are also presented.
The Application of Computational Fluid Dynamics to the Prediction of Flow Generated Noise in Low Speed Ducts. Part 1: Fluctuating Drag Forces on a Flow Spoiler
Authors: Mak C.M. , Oldham D.J. 
Published: January 2017

Nelson and Morfey have derived an expression for the sound power radiated from an in-duct spoiler subjected to the action of fluctuating drag forces arising from the flow turbulence in the vicinity of the spoiler. Although the derivation of an analytical expression for the fluctuating drag forces is impractical, an alternative approach could be the use of Computational Fluid Dynamics (CFD). The Navier-Stokes equations, which are the basis of CFD, provide a valid description of nearly all practically relevant flows including turbulent ones. However, in order to solve the relevant equations with sufficient accuracy to describe the fine detail of turbulent flow would mean working with a three dimensional mesh large enough to cover the region of interest but with spacing smaller than the smallest turbulent eddy present in the flow. Therefore the computational time required is unrealistically large even on modern super computers and using very efficient algorithms. In this paper an engineering approach is followed similar to that of Nelson and Morfey and other researchers to explore the possibility of an alternative method in which information provided by standard turbulence models can be employed as the basis of an airflow noise prediction method. In view of the success of early investigators in collapsing experimental data based upon the assumption of a proportional relationship between steady and fluctuating forces, an attempt was first made to confirm the validity of the model developed against this assumption using computational fluid dynamics. Experimental results presented by previous investigators have been processed and compared with CFD predictions. As well as providing a degree of validation for the approach developed in this paper, this investigation sheds further light on the assumption implicit in much of the early work of a single constant of proportionality relating the fluctuating to steady state drag forces.
Cholangiocarcinoma — Current Treatment Options
Authors: Friman S. 
Published: January 2017

The treatment for cholangiocarcinoma (CCA) remains a challenge because of the aggressive nature of the disease and the absence of effective treatments besides surgical resection (HR) and liver transplantation (LT). In intrahepatic CCA, HR remains the treatment of choice whereas with concomitant liver disease such as cirrhosis or primary sclerosing cholangitis (PSC), LT is the only option. Hilar CCA or Klatskin tumours have in recent decades been managed with a more aggressive surgical approach to achieve R0 resection. This approach usually involves preoperative portal embolisation, followed by liver resection — Sometimes extensive and even with portal vein resection. The recent protocols that combine preoperative neoadjuvant chemoirridation and LT show promising results that need to be confirmed. The development of diagnostic modalities (tumour markers, cytology and radiology) are of the utmost importance to identify these patients at an early stage to preserve radical surgery possible. Cholangiocarcinoma (CCA) is a malignant disease of the epithelial cells in the intra- and extrahepatic bile ducts. While still a rare malignant disease, CCA is the second most common primary malignancy of the liver. The incidence is increasing; especially the incidence of intrahepatic CCA (1). The treatment of CCA is challenging as it is usually difficult to diagnose when radical surgical treatment, resection (HR) or liver transplantation (LT) is possible. The lack of effective medical treatment makes a radical surgical resection or hepatectomy the only therapeutic option. Most of the CCAs are unresectable at presentation and the prognosis for these patients is dismal.
Spinal Epidural Arteriovenous Fistula: A Unique Pathway into the Perimedullary Vein
Authors: Lim S.M. , Choi I.S. 
Published: January 2017

Spinal dural arteriovenous fistulas (AVFs) are rare vascular malformations in the spinal dura, fed by dural branches of the radicular arteries, and drain primarily into intradural venous plexuses. They may cause elevated medullary venous pressure and produce a progressive myelopathy. We describe a case of AVF in the epidural space of the previous surgery site of L3 and it showed a unique complex venous pathway into the perimedullary vein, leading to classic clinical symptoms of venous congestion in the spinal cord. The shunt was draining into bilateral epidural venous plexus and then to the paravertebral veins at the level of L2. The venous outflow entered to the epidural space again and finally refluxed into the intradural perimedullary vein.
Difficulties with assessment and management of an infant’s distress in the postoperative period: Optimising opportunities for interdisciplinary information-sharing
Authors: Weiner Carlye , Penrose Sueann , Manias Elizabeth , Cranswick Noel , Rosenfeld Ellie , Newall Fiona , Williams Allison , Borrott Narelle , Kinney Sharon 
Published: January 2017

Objectives: The importance of accurate paediatric patient assessment is well established but under-utilised in managing postoperative medication regimens. Methods: Data for this case report were collected through observations of clinical practice, conduct of interviews, and retrieval of information from the medical record. This case report involving a hospitalised 1-year-old boy demonstrates the difficulties associated with assessing and managing postoperative distress, including pain and other clinical conditions related to the surgical procedure. Results: Postoperatively, there were difficulties in managing pain and an episode of over-sedation, occasioning opiate reversal with naloxone. In addition, he had decreasing oxygen saturation and increased work of breathing. X-ray showed changes consistent with either atelectasis or aspiration, and he was commenced on antibiotics. The patient experienced respiratory distress and required intervention from the medical emergency team. Conclusion: This case demonstrated the importance of comprehensive assessment and careful consideration of alternative causes of an infant’s distress using the results of assessment tools to aid decision-making. Communication moderates effective patient care, and more favourable outcomes could be achieved by optimising interdisciplinary information-sharing.
Recurrent unilateral facial nerve palsy in a child with dehiscent facial nerve canal
Authors: Liu Christopher , Ulualp Seckin O , Koral Korgun 
Published: January 2017

Objective: The dehiscent facial nerve canal has been well documented in histopathological studies of temporal bones as well as in clinical setting. We describe clinical and radiologic features of a child with recurrent facial nerve palsy and dehiscent facial nerve canal. Methods: Retrospective chart review. Results: A 5-year-old male was referred to the otolaryngology clinic for evaluation of recurrent acute otitis media and hearing loss. He also developed recurrent left peripheral FN palsy associated with episodes of bilateral acute otitis media. High resolution computed tomography of the temporal bones revealed incomplete bony coverage of the tympanic segment of the left facial nerve. Conclusions: Recurrent peripheral FN palsy may occur in children with recurrent acute otitis media in the presence of a dehiscent facial nerve canal. Facial nerve canal dehiscence should be considered in the differential diagnosis of children with recurrent peripheral FN palsy.
Electroacupuncture for the prevention of postoperative gastrointestinal dysfunction in participants undergoing vascular laparotomy under general anesthesia: a randomized controlled trial
Authors: Liu Meng-yue , Wang Cheng-wei , Wu Zhou-peng , Li Ning 
Published: January 2017

AbstractBackgroundPostoperative gastrointestinal dysfunction (PGD) is a common complication following laparotomy under general anesthesia (GA). Abdominal distension occurs in 8–28% of surgeries within 24 h postoperatively. The present study aimed to analyze the efficacy of electroacupuncture (EA) for the prevention of PGD by applying preoperative EA stimulation of PC6 (Neiguan), ST36 (Zusanli), and ST37 (Shangjuxv) bilaterally twice within 24 h prior to surgery, compared with no acupuncture treatment.MethodsThe study participants were assessed and selected from participants undergoing vascular laparotomy under GA at the Liver and Vascular Surgery Unit in West China Hospital of Sichuan University. The selected participants were randomly allocated to two groups: routine-treatment (RT) and EA group receiving EA at PC6, ST36, and ST37. A computer-generated list of random numbers was used to determine the allocation of the participants, with numbered opaque sealed envelopes containing the randomization schedule. Eligible participants were all adults aged 18 years or above who were scheduled to undergo vascular laparotomy under GA within 24 h and had no history of EA treatment. The exclusion criteria included participants with serious systemic disease and history of EA treatment. While the RT group received standard treatments, the EA group received additional EA treatments. During each treatment session, EA stimulation was performed for a duration of 20 min at a frequency of 15 Hz with a continuous wave. All such participants received two EA treatments within 24 h before surgery. The outcomes were measured in three metrics: incidence and degree of abdominal distension; first times of flatus and defecation; and duration of hospitalization.ResultsForty-three participants were recruited, of whom 42 participants successfully completed the study. Each group contained 21 participants. The incidence of abdominal distension (42.8, 76.2%) and degree of abdominal distension were significantly reduced in the EA group (P = 0.03 andP = 0.03, respectively). In comparisons of the first times of flatus (3.05 ± 0.58, 3.29 ± 0.42 days) and defecation (2.81 ± 0.51, 3.20 ± 0.55 days) and duration of hospitalization (5.33 ± 0.68, 5.75 ± 0.66 days), the EA group was superior to the RT group to some extent (P = 0.13,P = 0.02, andP = 0.04, respectively).ConclusionsPreoperative EA at PC6, ST36, and ST37 might be useful for preventing PGD, thereby improving gastrointestinal function recovery.Trial registrationThis study is registered with the Chinese Clinical Trial Registry: ChiCTR-TRC-13003649