Numerical investigation of the fatal 1985 Manchester Airport B737 fire

ABSTRACTIn this paper, fire and evacuation computer simulations are used to reconstruct the 1985 Manchester Airport B737 fire that resulted in the loss of 55 lives. First the actual fire and evacuation are reconstructed. Secondly, the impact of exit opening times and external wind on the fire and evacuation are investigated. Finally, the potential benefit offered by modern materials is evaluated. The results suggest that the number of fatalities could have been reduced by 87% had the forward right exit not malfunctioned and by 36% had the right over-wing exit been opened without delay. Furthermore, given the fuel pool size and location, a critical wind speed of 1.5m/s is necessary to cause the fire plume to lean onto the fuselage eventually resulting in fuselage burn-through. Finally, it is suggested that the use of modern cabin materials could have made a significant difference to the fire development and survivability.

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Stiffness of the Masseter Muscle in Children—Establishing the Reference Values in the Pediatric Population Using Shear-Wave Elastography

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18189619 ◽

2021 ◽

Vol 18 (18) ◽

pp. 9619

Author(s):

Cyprian Olchowy ◽

Anna Olchowy ◽

Aleksander Pawluś ◽

Mieszko Więckiewicz ◽

Luca Maria Sconfienza

Keyword(s):

Shear Wave ◽

Masseter Muscle ◽

Pediatric Population ◽

Shear Wave Elastography ◽

Total Sample ◽

Healthy Children ◽

Significant Difference ◽

The Right ◽

The Impact ◽

Masseter Muscles

In children, the quality and muscle function are altered in many pathologic conditions, including temporomandibular disorders. Although several methods have been used to evaluate muscle tonus, none became a golden standard. Moreover, the masseter muscle characteristics in children have not been investigated to date. This study aimed to measure the stiffness of the masseter muscle using shear-wave elastography in healthy children. We enrolled 30 healthy children (mean age 10.87 ± 3.38 years). The stiffness of masseter muscles was measured with shear wave elastography. Stiffness for the total sample was 6.37 ± 0.77 kPa. A comparison of the measurements did not show significant differences between the right and the left masseter muscles (left—6.47 ± 0.78 kPa; right—6.24 ± 0.76 kPa; p = 0.3546). A significant difference was seen between boys and girls (boys—5.94 ± 0.50 kPa; girls—6.63 ± 0.80; p = 0.0006). Shear-wave elastography is a promising diagnostic tool. It may help to detect changes in the stiffness of the masseter muscle and draw attention to pathological processes within the jaw muscles. Directions for further research shall include determining stiffness values in pathological conditions and the impact of biological and functional factors on the stiffness of the masseter muscle.

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Intelligence Deficits in Chinese Patients with Brain Tumor: The Impact of Tumor Resection

The Scientific World JOURNAL ◽

10.1155/2013/261236 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Chao Shen ◽

Rong Xie ◽

Xiaoyun Cao ◽

Weimin Bao ◽

Bojie Yang ◽

...

Keyword(s):

Brain Tumor ◽

Pituitary Adenoma ◽

Tumor Resection ◽

Chinese Patients ◽

Adult Intelligence Scale ◽

Wechsler Adult Intelligence Scale ◽

Significant Difference ◽

And Performance ◽

The Right ◽

The Impact

Background. Intelligence is much important for brain tumor patients after their operation, while the reports about surgical related intelligence deficits are not frequent. It is not only theoretically important but also meaningful for clinical practice.Methods. Wechsler Adult Intelligence Scale was employed to evaluate the intelligence of 103 patients with intracranial tumor and to compare the intelligence quotient (IQ), verbal IQ (VIQ), and performance IQ (PIQ) between the intracerebral and extracerebral subgroups.Results. Although preoperative intelligence deficits appeared in all subgroups, IQ, VIQ, and PIQ were not found to have any significant difference between the intracerebral and extracerebral subgroups, but with VIQ lower than PIQ in all the subgroups. An immediate postoperative follow-up demonstrated a decline of IQ and PIQ in the extracerebral subgroup, but an improvement of VIQ in the right intracerebral subgroup. Pituitary adenoma resection exerted no effect on intelligence. In addition, age, years of education, and tumor size were found to play important roles.Conclusions. Brain tumors will impair IQ, VIQ, and PIQ. The extracerebral tumor resection can deteriorate IQ and PIQ. However, right intracerebral tumor resection is beneficial to VIQ, and transsphenoidal pituitary adenoma resection performs no effect on intelligence.

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Vertical ground reaction force analysis during gait with unstable shoes

Fisioterapia em Movimento ◽

10.1590/0103-5150.028.003.ao04 ◽

2015 ◽

Vol 28 (3) ◽

pp. 459-466

Author(s):

Giulia Pereira ◽

Aluísio Otavio Vargas Avila ◽

Rudnei Palhano

Keyword(s):

Ground Reaction Force ◽

Reaction Force ◽

Force Plate ◽

Vertical Ground Reaction Force ◽

Significant Difference ◽

Vertical Ground ◽

The Subject ◽

Unstable Shoes ◽

The Right ◽

The Impact

AbstractIntroduction Footwear is no longer just an accessory but also a protection for the musculoskeletal system, and its most important characteristic is comfort.Objectives This study aims to identify and to analyze the vertical ground reaction force in barefoot women and women with unstable shoes.Methodology Five women aged 25 ± 4 years old and mass of 50 ± 7 kg participated in this study. An AMTI force plate was used for data acquisition. The 10 trials for each situation were considered valid where the subject approached the platform with the right foot and at the speed of 4 km/h ± 5%. The instable shoe of this study is used in the practice of physical activity.Results The results showed that the first peak force was higher for the footwear situation, about 5% and significant differences between the barefoot and footwear situation. This significant difference was in the first and second peaks force and in the time of the second peak.Conclusion The values showed that the footwear absorbs approximately 45% of the impact during gait.

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Multi-model comparison of urban heat island modelling approaches

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-10655-2018 ◽

2018 ◽

Vol 18 (14) ◽

pp. 10655-10674 ◽

Cited By ~ 9

Author(s):

Jan Karlický ◽

Peter Huszár ◽

Tomáš Halenka ◽

Michal Belda ◽

Michal Žák ◽

...

Keyword(s):

Wind Speed ◽

Urban Heat Island ◽

Urban Environment ◽

Model Comparison ◽

Climate Model ◽

Heat Island ◽

Significant Difference ◽

Urban Heat ◽

Urban Parameterizations ◽

The Impact

Abstract. Cities are characterized by different physical properties of surface compared to their rural counterparts, resulting in a specific regime of the meteorological phenomenon. Our study aims to evaluate the impact of typical urban surfaces on the central European urban climate in several model simulations, performed with the Weather Research and Forecasting (WRF) model and Regional Climate Model (RegCM). The specific processes occurring in the typical urban environment are described in the models by various types of urban parameterizations, greatly differing in complexity. Our results show that all models and urban parameterizations are able to reproduce the most typical urban effect, the summer evening and nocturnal urban heat island, with the average magnitude of 2–3 °C. The impact of cities on the wind is clearly dependent on the urban parameterization employed, with more simple ones unable to fully capture the wind speed reduction induced by the city. In the summer, a significant difference in the boundary-layer height (about 25 %) between models is detected. The urban-induced changes of temperature and wind speed are propagated into higher altitudes up to 2 km, with a decreasing tendency of their magnitudes. With the exception of the daytime in the summer, the urban environment improves the weather conditions a little with regard to the pollutant dispersion, which could lead to the partly decreased concentration of the primary pollutants.

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Influence of X Ray Computed Tomography (CT) Exposure and Reconstruction Parameters on Positron Emission Tomography (PET) Quantitation

10.21203/rs.3.rs-35526/v1 ◽

2020 ◽

Author(s):

Ivan Ho Shon ◽

Christopher Reece ◽

Thomas Hennessy ◽

Megan Horsfield ◽

Bruce McBride

Keyword(s):

Low Dose ◽

Reconstruction Algorithm ◽

Beam Hardening ◽

Low Dose Ct ◽

Ct Dose ◽

Positron Emission ◽

Significant Difference ◽

Pet Reconstruction ◽

The Right ◽

The Impact

Abstract Background:The CT of PET CT provides diagnostic information, anatomic localisation and attenuation correction (AC). When only ACis required very lose dose CT is desirable.CT Iterative reconstruction (IR) improves image quality with lower exposures however there is little data on very low dose IR CT for AC of PET. This work aims to assess the impact of CT exposure and reconstruction algorithm on PET voxel values.Method: An anthropomorphic torso phantom was filled with physiologically typical [18]F concentrations in heart, liver and background compartments. A 17mm diameter “tumour” was included in the right lung. PET was acquired followed by 24 CT acquisitions with varying CT exposures (15-50mAs, 80 – 120kVp, pitch 0.671 - 0.828). Each CT was reconstructed twice using filtered back projection (FBP) or IR and these used for AC of PET. Regions of interest (ROIs) were drawn in liver, soft tissue and over “tumour” on each test reconstruction (TR) and compared with the reference reconstruction (RR), (50mAs, 120kVp, pitch 0.828, IR). Comparison of voxel values in each TR compared to the RR was undertaken using a paired t-test and by calculating which and what proportion of voxels in each TR differed by a quantitatively significant difference (QSD) from the corresponding RR voxel.Results: TRs reconstructed using lower dose CTs underestimated mean and maximum ROI activity relative to the RR; greater with IR than FBP. Once CT dose index (CTDI)increased to 1 mGythe differences were less than QSD. On voxel analysis all TRs were significantly different to the RR (p <0.0001). TRs reconstructed at the lowest CT exposure with IR had 6% of voxels that differed by greater than the QSD. Differences were reduced with increasing CTDI and FBP reconstruction. Voxels which exceeded the QSD were spatially localised to regions of high activity, at interfaces between different attenuation and in areas of CT beam hardening.Conclusions: Very low dose CT exposures are feasible for accurate PET AC. Scanner specific validation should be employed prior very low dose CT AC for PET reconstruction.

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The SME Condition During Covid 19 Pandemic: Financial And Business Overview

International Journal of Science, Technology & Management ◽

10.46729/ijstm.v2i3.211 ◽

2021 ◽

Vol 2 (3) ◽

pp. 718-727

Author(s):

Khalisa Rahmina Suryani ◽

Rizka Zulfikar ◽

Aida Vitria

Keyword(s):

Raw Materials ◽

Descriptive Analysis ◽

Work Productivity ◽

Validity And Reliability ◽

Quantitative Descriptive Analysis ◽

Financial Condition ◽

Significant Difference ◽

Business Conditions ◽

The Right ◽

The Impact

The Covid-19 outbreak has become a global problem and has caused economicproblems in various sectors including the SME sector. This research was conductedto examine the impact of the Covid-19 pandemic on the business conditions of SMEswhich later can be used by policy makers in determining the right actions toovercome financial problems in the SME sector.This research was conducted in the province of South Kalimantan using primarydata. Sampling was done by purposive sampling with an instrument in the form of aquestionnaire. This study used a sample of 233 respondents. The data analysistechnique was performed using the analysis of the validity and reliability of theinstrument and quantitative descriptive analysis to describe the financial conditionsof SMEs and the affected business / corporate sectors. The results of this study foundthat (1) There was a significant difference to the financial condition of SMEs beforeand after the pandemic, where there was a decrease in gross income (-41.6%) andthe level of profit in the SME sector (-62.8%) in general (2) Some of the impacts ofthe Covid Pandemic -19 regarding the business conditions of SMEs, namely (a)there are still many SMEs that have not been able to sell online, (b) there has beenan increase in raw materials, (c) the majority of SMEs have difficulty obtaining rawmaterials, (d) there is a decrease in motivation and work productivity which issignificant, (e) there are still many SMEs that experience a shortage of cash andmany SMEs are in arrears of liabilities, (f) but the majority of SMEs still believethey will survive and pass the pandemic.

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Multi-model comparison of urban heat island modelling approaches

10.5194/acp-2018-3 ◽

2018 ◽

Author(s):

Jan Karlický ◽

Peter Huszár ◽

Tomáš Halenka ◽

Michal Belda ◽

Michal Žák ◽

...

Keyword(s):

Wind Speed ◽

Urban Heat Island ◽

Urban Environment ◽

Model Comparison ◽

Urban Climate ◽

Weather Conditions ◽

Heat Island ◽

Significant Difference ◽

Urban Heat ◽

The Impact

Abstract. Cities are characterized by different physical properties of surface compared to their rural counterparts, resulting in specific regime of the meteorological phenomenon. Our study aims to evaluate the impact of typical urban surfaces on the central-European urban climate in several model simulations, performed with the WRF and RegCM models. The specific processes occurring in the typical urban environment are described in the models by various types of urban parametrizations, greatly differing in complexity. Our results show that all models and urban parametrizations are able to reproduce the most typical urban effect, the summer evening and nocturnal Urban Heat Island, with the average magnitude of 2–3 °C. The impact of cities on the wind is clearly dependent on the urban parametrization employed, with more simple ones unable to fully capture the wind speed reduction induced by the city. In the summer, a significant difference in the boundary layer height (about 25 %) between models is detected. The urban induced changes of temperature and wind speed are propagated into higher altitudes up to 2 km, with a decreasing tendency of their magnitudes. With the exception of the summer daytime, the urban environment improves the weather conditions a little with regard to the pollutant dispersion, which could lead to the partly decreased concentration of the primary pollutants.

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Distribution of Iliac Artery Calcification on Unenhanced Computed Tomography Scans Performed on Potential Recipients Prior to Renal Transplantation

Canadian Association of Radiologists Journal ◽

10.1177/0846537119899535 ◽

2020 ◽

pp. 084653711989953

Author(s):

Adrian Marcuzzi ◽

Stella Wang ◽

Pascal N. Tyrrell ◽

Pradeep Ravichandran ◽

Danny Marcuzzi ◽

...

Keyword(s):

Computed Tomography ◽

Estimating Equation ◽

Generalized Estimating Equation ◽

Clinical Factors ◽

Iliac Arteries ◽

Significant Difference ◽

Unenhanced Computed Tomography ◽

The Right ◽

The Impact ◽

Generalized Estimating

Purpose: To investigate whether a significant difference exists between the calcification of the common iliac arteries (CIAs) and the external iliac arteries (EIAs) and test for associations between clinical factors and the distribution of calcification. Methods: A retrospective review of renal transplant candidates who underwent a routine preoperative unenhanced computed tomography yielded 214 patients. Agatston scores for the patients’ left CIA, left EIA, right CIA, and right EIA were assigned. A retrospective search of patient records screened for 5 clinical factors (diabetes, hypertension, coronary artery disease [CAD], smoking, and dialysis). Data were assessed using a 2-sided t test, odds ratio, and a multivariate linear regression calculated through generalized estimating equation (GEE). Results: The log-transformed Agatston scores in the CIA were found to be significantly greater than that in the EIA ( t = 9.57, P < .0001), with a mean difference of 1.5078 (95% confidence interval: 1.1962-1.8194), indicating relative EIA sparing. There were no significant differences in calcification between the right and left sides. Generalized estimating equation found that CAD and smoking demonstrated independent positive associations with EIA sparing (GEE = 2.6464 [ P = .0197] and 1.9092 [ P = .0470], respectively). Age was also significantly associated and indicated that EIA sparing remained relatively constant throughout patients’ lives (GEE = 1.0711 [ P < .0001]). Conclusion: This study has demonstrated statistically significant EIA sparing in end-stage renal disease patients and identified CAD and smoking as associated factors. This phenomenon warrants further investigation into its biological mechanisms and the impact of EIA sparing on outcomes following transplants.

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The effect of head tilt angle in the roll plane on the virtual subjective visual vertical results in healthy adults

Auditory and Vestibular Research ◽

10.18502/avr.v30i1.5307 ◽

2021 ◽

Author(s):

Mahmoud Rezvani Amin ◽

Moslem Shaabani ◽

Mohsen Vahedi

Keyword(s):

Tilt Angle ◽

Head Tilt ◽

Healthy Adults ◽

Subjective Visual Vertical ◽

Substantial Impact ◽

Normal Individuals ◽

Significant Difference ◽

Visual Vertical ◽

The Right ◽

The Impact

Background and Aim: The subjective visual vertical (SVV) is commonly considered as an indicator of the sense of orientation and attributed to the utricular function. The present study examined the impact of different head tilt angles on SVV among the normal individuals. Methods: SVV was measured in 47 normal participants (30 males and 17 females; mean ± SD age: 22.14 ± 3.46) using a virtual goggle and forced-choice paradigm and was applied twice in 0º, 15º, 30° and 45º to the left or to the right. In addition, difference in mean of SVV in zero and non-zero positions was compared. Results: There was a statistically significant difference between the mean SVV results of 0º and 15º (p ˂ 0.001). The comparison of mean SVV results between 0º and 30º, and between 0º and 45º were not significant (p > 0.05). In addition, comparison of SVV results between rightward and leftward tilt of 15º was statistically significant (p ˂ 0.001). The latter comparison was not significant for 30º and 45º (p > 0.05). Conclusion: Our results showed that head tilt angle of 15º have a substantial impact on the virtual SVV. These findings must be taken into account in the growing body of research that uses the SVV paradigm in clinical populations. Keywords: Head tilt angle; subjective visual vertical; virtual goggle; roll plane; utricle; healthy adults

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Evaluation of Subclinical Hypothyroidism on Auditory Divided Attention

Journal of Modern Rehabilitation ◽

10.18502/jmr.v13i1.2145 ◽

2019 ◽

Author(s):

Fatemeh Khorasani ◽

Nematollah Rouhbakhsh ◽

Ahmad Geshani ◽

Mohammad Reza Mohajeri Tehrani ◽

Mostafa Qorbani

Keyword(s):

Divided Attention ◽

Subclinical Hypothyroidism ◽

Thyroid Stimulating Hormone ◽

Control Group ◽

Cross Sectional ◽

Endocrine Disorder ◽

Significant Difference ◽

Healthy Control ◽

The Right ◽

The Impact

Introduction: Subclinical hypothyroidism is an endocrine disorder that can adversely affect cognitive performance. In this regard, patients with subclinical hypothyroidism may develop poor attention. However, the effects of this endocrine disorder on auditory attention is unclear. This study aims to evaluate the impact of subclinical hypothyroidism on auditory divided attention. Materials and Methods: This cross-sectional, case control study was performed on 30 adult patients, aged 20-40 years, who met the study inclusion criteria. Based on their Thyroid Stimulating Hormone (TSH) level, the subjects were divided into two case groups (each with 15 patients) with a TSH level of 5˂TSH≤10 and 10˂TSH≤15. A healthy control group was recruited with matched age, sex, and education with the case groups. The participants were evaluated by the Persian version of the Bergen dichotic listening test. Among different experimental situations that included non-forced attention, forced right, and forced left, we chose the non-forced attention. Statistical analysis was done in SPSS V. 25. Results: There was a significant difference between the subclinical hypothyroid (5˂TSH≤10 group) and controls in the scores of the right and left ear. However, there was no significant difference between scores of right and left ear in subclinical hypothyroid (10˂TSH≤15 group). No significant difference in scores of the right and left ear was found between men and women in three groups. Conclusion: Subclinical hypothyroidism had no effect on auditory divided attention.

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