Latency in onset of decompression sickness on direct ascent from air saturation

1984 ◽  
Vol 56 (4) ◽  
pp. 1070-1075 ◽  
Author(s):  
R. G. Eckenhoff ◽  
J. W. Parker
Keyword(s):  
Decompression Sickness ◽  
Human Subjects ◽  
Compressed Air ◽  
Inert Gas ◽  
Practical Application ◽  
Threshold Time ◽  
The Mean ◽  
Sufficient Magnitude ◽  
The Relationship

Twenty-four human subjects were exposed to compressed air at simulated depths ranging from 45 ft seawater gauge (fsw) (2.36 ATA) to 75 fsw (3.27 ATA) for periods of time sufficient to allow saturation of most tissues with inert gas. From each of four depths (45, 55, 65 and 75 fsw), subjects ascended directly to 1 ATA, where they remained for 30, 17, 13, and 10 min, respectively. During this time the onset of Doppler detected venous gas emboli (VGE), pruritus, and any other symptomatology was monitored and recorded. In the ascending excursion from 45 fsw (n = 18), the mean appearance times of pruritus and VGE were 19.3 +/- 7.5 (mean +/- SD) and 21.9 +/- 7.4 min, respectively, with one case of pain-only decompression sickness (DCS). The excursion from 55 fsw (n = 17) shortened these times to 9.2 +/- 3.3 and 14.4 +/- 3.2 min, respectively, with two cases of DCS, one each of pain-only and serious types. In the excursion from 65 fsw (n = 23), mean pruritus and VGE appearance times were 6.3 +/- 1.4 and 10.8 +/- 1.9 min, respectively, with no cases of DCS. The excursion from 75 fsw (n = 6) resulted in appearance times of 4.8 +/- 0.8 and 8.2 +/- 1.2, respectively, with one case of pain-only DCS. Sufficient cases of DCS did not occur in any of the excursions to allow determination of mean appearance times. The relationship between pressure reduction and appearance times of pruritus and VGE, and the threshold time of DCS, can be described mathematically. We conclude that latency in the development of DCS on direct ascent from air saturation exists and is of sufficient magnitude to permit practical application in emergency decompressions or unpressurized transfers between compressed air or N2-O2 environments.

Consideration of Environmentally Assisted Fatigue in Austenitic Stainless Steel: Calculation and Practical Application

2012 ◽  
Author(s):  
Sven H. Reese ◽  
Johannes Seichter ◽  
Dietmar Klucke
Keyword(s):  
Primary Circuit ◽  
Stress And Strain ◽  
Loading Conditions ◽  
Practical Application ◽  
Circuit Component ◽  
Detailed Assessment ◽  
The Mean ◽  
Fatigue Evaluation ◽  
Assessment Procedures

The influence of LWR coolant environment to the lifetime of materials has been discussed recent years. Nowadays the consideration of environmentally assisted fatigue is under consideration in Codes and Standards like ASME and the German KTA Rules (e.g. Standard No. 3201.2 and Standard No. 3201.4) by means of so called attention thresholds. Basic calculation procedures in terms of quantifying the influence of LWR coolant environment by the Fen correction factor were proposed by Higuchi and others and are given in NUREG/CR-6909. This paper deals with the application of the proposed assessment procedures of ANL and the application to plant conditions. Therefore conservative assessment procedures are introduced without assuming the knowledge of detailed stress and strain calculations or temperature transients. Additionally, detailed assessment procedures based on Finite-Element calculations, respecting in-service temperature measurements including thermal reference transients and complex operational loading conditions are carried out. Fatigue evaluation of a PWR primary circuit component is used in order to evaluate the influence of plant like conditions numerically. Conclusions regarding the practical application are drawn by means of comparing the ANL approach considering laboratory conditions, conservative assessment procedures for the determination of cumulative fatigue usage factors of plant components and detailed assessment procedures. Plant like loading conditions, complex component geometries, loading scenarios and reference temperature transients shall be taken into account. Practical issues like the determination of the mean temperature or the strain rate have to be considered adequately.

scholarly journals Relationship between Body Mass Index and Tooth Decay in a Population of 3–6-Year-Old Children in Iran

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Leila Shafie Bafti ◽  
Maryam Alsadat Hashemipour ◽  
Hamidreza Poureslami ◽  
Zeinab Hoseinian
Keyword(s):  
Body Weight ◽  
Analytical Study ◽  
Deciduous Teeth ◽  
Tooth Decay ◽  
Cross Sectional ◽  
Dmft Index ◽  
The Mean ◽  
Iranian Children ◽  
The Relationship

The aim of the present study was to evaluate the relationship between BMI and tooth decay in a population of Iranian children. In this cross-sectional descriptive/analytical study, 1482 children were selected from kindergartens and preschool centers in Kerman, Iran. The children underwent examination of deciduous teeth (using the dmft index) after determination of height and weight for calculation of BMI. The relationship between BMI (after adjustment for age) and dmft was determined using Poisson’s regression model. The mean of dmft in children with normal BMI was 1.5-fold that in subjects with extra body weight. Age had a significant effect on dmft. In addition, dmft was higher in boys compared to girls. The results of the present study showed that caries rate in the deciduous teeth of 3–6-year-old children decreases with an increase in body weight.

scholarly journals Determination of receptor occupancy in the presence of mass dose: [11C]GSK189254 PET imaging of histamine H3 receptor occupancy by PF-03654746

2016 ◽  
Vol 37 (3) ◽  
pp. 1095-1107 ◽  
Author(s):  
Jean-Dominique Gallezot ◽  
Beata Planeta ◽  
Nabeel Nabulsi ◽  
Donna Palumbo ◽  
Xiaoxi Li ◽  
...  
Keyword(s):  
Binding Sites ◽  
Human Subjects ◽  
Receptor Occupancy ◽  
Healthy Human ◽  
Positron Emission ◽  
Relationship Of ◽  
The Relationship ◽  
Pet Scans

Measurements of drug occupancies using positron emission tomography (PET) can be biased if the radioligand concentration exceeds “tracer” levels. Negative bias would also arise in successive PET scans if clearance of the radioligand is slow, resulting in a carryover effect. We developed a method to (1) estimate the in vivo dissociation constant Kd of a radioligand from PET studies displaying a non-tracer carryover (NTCO) effect and (2) correct the NTCO bias in occupancy studies taking into account the plasma concentration of the radioligand and its in vivo Kd. This method was applied in a study of healthy human subjects with the histamine H3 receptor radioligand [11C]GSK189254 to measure the PK-occupancy relationship of the H3 antagonist PF-03654746. From three test/retest studies, [11C]GSK189254 Kd was estimated to be 9.5 ± 5.9 pM. Oral administration of 0.1 to 4 mg of PF-03654746 resulted in occupancy estimates of 71%–97% and 30%–93% at 3 and 24 h post-drug, respectively. NTCO correction adjusted the occupancy estimates by 0%–15%. Analysis of the relationship between corrected occupancies and PF-03654746 plasma levels indicated that PF-03654746 can fully occupy H3 binding sites ( ROmax = 100%), and its IC50 was estimated to be 0.144 ± 0.010 ng/mL. The uncorrected IC50 was 26% higher.

scholarly journals DETERMINATION OF THE COMBINED WIDTH OF MAXILLARY ANTERIOR TEETH USING INNERCANTHAL DISTANCE WITH RESPECT TO AGE GENDER AND ETHINICITY

2021 ◽  
Vol 71 (Suppl-1) ◽  
pp. S164-69
Author(s):  
Naseer Ahmed ◽  
Maria Shakoor Abbasi ◽  
Danish Azeem Khan ◽  
Shiza Khalid ◽  
Warda Jawed ◽  
...  
Keyword(s):  
Cross Sectional Study ◽  
Gender Disparities ◽  
Sectional Study ◽  
Weak Correlation ◽  
Cross Sectional ◽  
Anterior Teeth ◽  
Significant Difference ◽  
The Mean ◽  
The Relationship

Objective: To evaluate the relationship between inner canthal distance and maxillary anterior teeth width withrespect to age, gender and ethnicity. Study Design: Cross sectional study. Place and Duration of Study: Altamash Institute of Dental Medicine, Karachi, from Aug 2019 to Jan 2020. Methodology: One hundred participants from both genders with full permanent dentition, no interdental space or pathology and facial symmetry were included in this study. The measurements were carried out with digital Vernier caliper. SPSS-25 was used for statistical analysis. Results: The mean ± SD of inner canthal distance and width of maxillary anterior teeth were 2.99cm ± 0.46and 3.82cm ± 0.35 respectively. A significant difference was found between gender (p=0.037) and inner canthaldistance. The maxillary anterior teeth width and inner canthal distance varies amongst different ethnicities(p=0.01). The inner canthal distance does not vary with advancing age (p=0.87) whereas width of maxillaryanterior teeth varies (p=0.04). A weak correlation value of 0.47 was found between inner canthal distance andmaxillary anterior teeth width. Conclusion: This research suggests that there is a weak relationship between inner canthal distance and maxillary anterior teeth width. Therefore, a multiplication ratio of 1.27 is advised to get combined mesiodistal width of maxillary anterior teeth. Additionally, the value of both differs in various local ethnicities. Inner canthal distance does not vary with age though has significant gender disparities while maxillary anterior teeth width remains constant.

Inert gas a-A differences: a direct reflection of V/Q distribution

1978 ◽  
Vol 44 (2) ◽  
pp. 277-283 ◽  
Author(s):  
G. R. Neufeld ◽  
J. J. Williams ◽  
P. L. Klineberg ◽  
B. E. Marshall
Keyword(s):  
Quantitative Information ◽  
Inert Gas ◽  
The Mean ◽  
Log Normal ◽  
The Relationship ◽  
Log Normal Distribution ◽  
Direct Reflection ◽  
Direct Calculations ◽  
Difference Plot ◽  
Inert Gas Retention

A computer model was developed to study the relationship between ventilation-to-perfusion (V/Q) mismatch and the development of inert gas arterial-to-alveolar partial pressure differences (a-A differences). Increasing inhomogeneity of V/Q ratio is revealed directly as an increase in the a-A difference of each gas. The quantitative relationships between the Q vs. V/Q distribution and the fractional a-A difference solubility plot (a-A difference plot) were studied and described. These studies demonstrated that for log normally distributed V/Q ratios, the area under the a-A difference plot is linearly related to the log variance of the V/Q distribution and can be estimated directly from the values obtained from six gases. The maximum a-A difference occurs for a gas whose solubility is numerically equal to the mean V/Q. The effects of departure from log normality and multimodality are discussed. We conclude from these studies that quantitative information regarding the degree of inhomogeneity of V/Q for log normal distribution is available from direct calculations of inert gas retention and excretion data. Qualitative information is also available indicating the departure from log normality and the region toward which the distribution is skewed.

The Effect of Breastfeeding on Fertility in Bangladesh

2002 ◽  
Vol 21 (3) ◽  
pp. 283-290
Author(s):  
Ahmad Kabir ◽  
Mohammad Fahimul Islam
Keyword(s):  
Path Analysis ◽  
Child Mortality ◽  
Health Survey ◽  
Demographic And Health Survey ◽  
Live Births ◽  
The Mean ◽  
Significant Change ◽  
Duration Of Breastfeeding ◽  
The Relationship

This study, based on the 1996–97 Bangladesh Demographic and Health Survey, attempts to find the effect of breastfeeding on fertility. The study reveals that breastfeeding status of the mothers placed a considerable role in the determination of fertility. The mean number of live births was lower in case of mothers who gave full breastfeeding compared to others. The relationship between the duration of breastfeeding and mean number of live births was direct and negative. A significant change in the breastfeeding pattern was observed by parity and age of mothers. The path analysis suggests that the longer the duration of breastfeeding, the lower will be the incidence of child mortality, and hence the lower will be the fertility.

Studies in grazing management V. Further determination of the nutrient intake of dairy cows under close-folding and rotational methods of grazing

1952 ◽  
Vol 42 (3) ◽  
pp. 314-321 ◽  
Author(s):  
R. Waite ◽  
W. Holmes ◽  
J. Boyd
Keyword(s):  
Standard Deviation ◽  
Chemical Composition ◽  
Dairy Cows ◽  
Nutrient Intake ◽  
Dry Matter ◽  
Balance Sheet ◽  
Adequate Quantity ◽  
The Mean ◽  
The Relationship

1. The experiments started in 1949 to determine the weight and chemical composition of the herbage dry matter eaten by two groups of dairy cows grazing under a rotational and a close-folding system of management have been continued in 1950.2. Good-quality herbage was fed in adequate quantity to both groups for 20 weeks, in four fiveweekly periods allowing a double change-over system for the groups. The weights of protein, fibre, other extractives, lignin and minerals eaten daily by the close-folded group were determined. Difficulty in obtaining truly representative herbage samples from the rotational paddock made such detailed analyses for the rotationally grazed cattle not worth while.3. The weight of dry matter eaten by the closefolded cows was remarkably constant, the mean was 26 lb./cow/day and the standard deviation ±2·7 lb. The weight eaten by the rotationally grazed cows was more difficult to measure and appeared to vary considerably, the average being 31 lb. dry matter/ cow/day, and the standard deviation ±3·1 lb. Reasons are suggested why this figure of 31 lb. may be at least 5% too high.4. The relationship between the chemical composition of herbage as cut for sampling and the probable composition of the herbage as eaten by the grazing animal is discussed. Correction curves are given to convert the protein and fibre contents of herbage as cut in these experiments to values corresponding to those in the herbage as eaten.5. An attempt has been made to provide a balance sheet, in terms of D.C.P. and S.E., of animal production against nutrient intake. A deficiency of both protein and energy existed during the first spring period in both 1949 and 1950 (according to presentday standards), and although the protein balance became positive later in the season, the energy provided by the grass eaten was still barely adequate.6. Mineral balances calculated for the closefolded cows showed deficiencies of both calcium and phosphorus during the period of high milk yield, with the balances becoming positive later in the grazing season.

scholarly journals Hemispheric lateralization of depression and attention deficit

2020 ◽  
Vol 7 (2) ◽  
pp. 409-411
Author(s):  
Büşra Sümeyye Arıca Polat ◽  
Akçay Övünç Özen ◽  
Ömer Karadaş
Keyword(s):  
Attention Deficit ◽  
Right Hemisphere ◽  
Cerebrovascular Diseases ◽  
Cognitive Status ◽  
Hemispheric Lateralization ◽  
Lesion Side ◽  
Ischemic Cerebrovascular Diseases ◽  
The Mean ◽  
The Relationship

Objective:  There is a complex interaction among to the ischemic cerebrovascular diseases, cognition and depression. The aim of present study is to investigate the relationship between lesion side and depression and attention deficit in patients with Middle Cerebral Artery (MCA) infarction. Methods: This study was conducted on 41 patients with right and left MCA infarction. Beck Depression Inventory (BDI) was used for determination of depression severity of patients and Montreal Cognitive Assessment (MoCA) scoring was used for evaluation of cognitive status. Attention sub-test of MoCA score was also examined. Results: 20 patients had right MCS.  The mean age of the patients was 72.21 years. 51.2% of the patients were male. BDI mean score was found to be 11.25 in patients with right MCA infarction and 16.9 in patients with left MCA infarction (p:0.04). The total MoCA scores between two groups were similar (right/left MCA infarction: 20.8/21.3). It was seen to be lower attention sub-score in patients with right hemisphere effects compared to patients with left hemispheric lesion (3.1/5.9; p:0.00). Conclusion: According to our findings, it is understood that attention of patients with right MCA infarction is more affected and patients with left MCA infarction is more depressed. In future studies, depression and attention affects which are at risk of developing after MCA infarctions should be evaluated in detail and should be put emphasis to rehabilitation of these areas.

Computer-Aided Technique for Automatic Determination of the Relationship between Transglottal Pressure Change and Voice Fundamental Frequency

2008 ◽  
Vol 117 (12) ◽  
pp. 876-880 ◽  
Author(s):  
Shinji Deguchi ◽  
Kazutaka Kawashima ◽  
Seiichi Washio
Keyword(s):  
Fundamental Frequency ◽  
Vocal Fold ◽  
Human Subjects ◽  
Pressure Change ◽  
Automatic Determination ◽  
Computer Aided ◽  
Voice Fundamental Frequency ◽  
The Relationship ◽  
The Voice

Objectives: The effect of artificially altered transglottal pressures on the voice fundamental frequency (F0) is known to be associated with vocal fold stiffness. Its measurement, though useful as a potential diagnostic tool for noncontact assessment of vocal fold stiffness, often requires manual and painstaking determination of an unstable F0 of voice. Here, we provide a computer-aided technique that enables one to carry out the determination easily and accurately. Methods: Human subjects vocalized in accordance with a series of reference sounds from a speaker controlled by a computer. Transglottal pressures were altered by means of a valve embedded in a mouthpiece. Time-varying vocal F0 was extracted, without manual procedures, from a specific range of the voice spectrum determined on the basis of the controlled reference sounds. Results: The validity of the proposed technique was assessed for 11 healthy subjects. Fluctuating voice F0 was tracked automatically during experiments, providing the relationship between transglottal pressure change and F0 on the computer. Conclusions: The proposed technique overcomes the difficulty in automatic determination of the voice F0, which tends to be transient both in normal voice and in some types of pathological voice.

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