Transmission to the chest of sound introduced at the mouth

We examined the transmission to the chest wall of white noise and 25-Hz square-wave-generated noise introduced at the mouth of five healthy subjects. The output audio signals were recorded over the left and right upper and lower lung zones, posteriorly. Sound measurements were made during apnea at functional residual capacity, total lung capacity, and residual volume both after breathing air and an 80% He-20% O2 (heliox) gas mixture. We calculated the peak-to-peak amplitude, the peak frequency, and the midpower frequency of the output sound. We found no consistent variations in the values of these indexes due to lung volume or resident gas density. In all cases, the transmitted sound was most intense at the right upper zone. This could not be explained on the basis of technical factors but was probably the result of normal asymmetry of the mediastinal anatomy. These data suggest that sound introduced through the mouth of healthy individuals excites intrathoracic structures but is transmitted through the parenchyma in such a manner that it is not markedly affected by familiar physiological variables. This must be taken into account if objective acoustical tests of lung physiology are to be developed.     

Respiratory transfer impedances with pressure input at the mouth and chest

Two methods of measuring respiratory transfer impedance (Ztr) were compared in 14 normal subjects, from 4 to 30 Hz, 1) studying the relationship between transrespiratory pressure (Prs) and flow at the chest when varying pressure at the mouth (Ztrm) and 2) studying the relationship between Prs and flow at the mouth when varying pressure around the chest wall (Ztrw). The similarity of the two relationships was expected on the basis of a T-network model. Almost identical phase responses were obtained from the two methods. Pressure-flow ratios were slightly larger for Ztrw than for Ztrm, but differences did not exceed 2% on average in 11 of 14 subjects. When the data were analyzed with the six-coefficient model proposed by DuBois et al. (J. Appl. Physiol. 8: 587-594, 1956), similar values were found for tissue compliance and tissue inertance but slightly different values for gaseous inertance in the airways (1.97 +/- 0.35 X 10(-2) cmH2O X l-1 X s2 for Ztrw vs. 1.73 +/- 0.26 for Ztrm; P less than 0.01). Similar results were also found for total respiratory resistance but with a slightly larger contribution of airway resistance for Ztrw (64 +/- 14 vs. 57 +/- 10%; P less than 0.05). As a practical conclusion it is recommended to measure Ztrw, which is technically much easier.     

Relation of mouth flow to body surface flow during forced oscillation at the chest

We have investigated the body surface flow/mouth flow transfer function (magnitude ratio and phase difference) in seven healthy male subjects driven at the chest from 4 to 30 Hz. The measurements were performed with a specially designed plethysmograph and analyzer. The subjects were driven with a mechanical oscillator placed on the sternum. After differences in gas temperature and humidity were taken into account, the data were in agreement up to 15 Hz with a simple second-order model including an airway compartment, with a resistance and an inertance, and a shunt compliance representing alveolar gas. At larger frequencies, closer inspection revealed that a third-order model was optimal. We interpret these results as indicating a compartmentalization of gas compliance within the thorax, communicating via a resistive element. Airway inertance did not seem to be distributed.     

Oligochaete communities at the mouth of the Neva and their relationship to anthropogenic impact

Changes in the oligochaete community of the Neva Mouth for the period 1982–1993 are discussed in relation to anthropogenic impacts. A number of community parameters such as species composition, biomass and diversity were generally stable, although local changes were noted. Predominance of eutrophic species, i.e. L. hoffmeisteri, T. tubifex, P. hammoniensis was enhanced, whereas mesotrophic and oligotrophic species — L. isoporus, S. heringianus, T. newaensis disappeared or became less numerous at some stations. The reverse trend was observed at other stations. These phenomena were accompanied by a sharp increase in the variability of biomass and/or diversity, which is regarded as exceeding normal annual fluctuations. The oligochaete community is recognized as a promising indicator of the ecological situation in the Neva Mouth.     

The relationship between megakaryocyte ploidy and platelet volume

The origins and biologic significance of platelet heterogeneity in general, and platelet volume heterogeneity in particular, have been controversial scientific issues during the past decade. Although it has generally been held that specific megakaryocyte properties, especially ploidy level, are important determinants of platelet volume, the precise relationship between megakaryocyte properties and platelet properties is not well defined. The physiologic processes that specifically determine the relationship between megakaryocyte ploidy and platelet volume are unclear, and understanding of these processes has been further complicated due to the multiplicity of experimental and clinical models used to study the problem. Although it is generally true that increases in megakaryocyte ploidy are associated with increases in megakaryocyte volume, it is not well established that platelet volume is also increased during normal or abnormal thrombopoiesis as a direct result of a change in the ploidy level. Reexamination of earlier studies and some recent investigations suggest that changes in platelet volume and megakaryocyte ploidy are in fact dissociated in response to experimental thrombocytopenia. Critical review of the literature concerning the relationship between megakaryocyte ploidy and platelet volume reveals a limited number of conclusions that are well substantiated and emphasizes the relative lack of understanding about the events governing the complex process of platelet production and platelet heterogeneity.     

Patterns and variations in the relationship between infant mortality and socioeconomic status

Abstract

This study utilizes an ecological approach based on census tracts of residence to examine the relationship between infant mortality and socioeconomic status in metropolitan Ohio at two points in time (1959–61 and 1969–71). The data presented clearly indicate that the infant mortality rate continues to exhibit a pronounced inverse association with a wide variety of socio‐economic variables. Although there were some notable exceptions and/or variations from the general patterns, a basic inverse relationship was generally found to be characteristic of both neonatal and postnatal components of infant mortality, for both males and females, and for both major exogenous and endogenous causes of death. Of all the variables examined, the one factor that emerged as the strongest and most consistent determinant of census tract variations in infant mortality was the proportion of low income families. Thus, the overriding conclusion suggested by this study is that in spite of such things as continued advances in medicine and public health, the expansion of a variety of social programs during the 1960's, and the recent resumption of a downward trend in the overall infant mortality rate, there has been little if any progress in achieving more equitable life chances for the economically deprived segments of our population.     

The relationship between settled volume and displacement volume in samples of freshwater zooplankton

The results of some volume estimates of zooplankton biomassare presented. The results suggest that, with freshwater zooplankton,the relationship between settled volume and displacement volumeremains relatively constant despite seasonal variations in speciescomposition.     

Diaphragm curvature modulates the relationship between muscle shortening and volume displacement

During physiological spontaneous breathing maneuvers, the diaphragm displaces volume while maintaining curvature. However, with maximal diaphragm activation, curvature decreases sharply. We tested the hypotheses that the relationship between diaphragm muscle shortening and volume displacement (VD) is nonlinear and that curvature is a determinant of such a relationship. Radiopaque markers were surgically placed on three neighboring muscle fibers in the midcostal region of the diaphragm in six dogs. The three-dimensional locations were determined using biplanar fluoroscopy and diaphragm VD, curvature, and muscle shortening were computed in the prone and supine postures during spontaneous breathing (SB), spontaneous inspiration efforts after airway occlusion at lung volumes ranging from functional residual capacity (FRC) to total lung capacity, and during bilateral maximal phrenic nerve stimulation at those same lung volumes. In supine dogs, diaphragm VD was approximately two- to three-fold greater during maximal phrenic nerve stimulation than during SB. The contribution of muscle shortening to VD nonlinearly increases with level of diaphragm activation independent of posture. During submaximal diaphragm activation, the contribution is essentially linear due to constancy of diaphragm curvature in both the prone and supine posture. However, the sudden loss of curvature during maximal bilateral phrenic nerve stimulation at muscle shortening values greater than 40% (ΔL/L(FRC)) causes a nonlinear increase in the contribution of muscle shortening to diaphragm VD, which is concomitant with a nonlinear change in diaphragm curvature. We conclude that the nonlinear relationship between diaphragm muscle shortening and its VD is, in part, due to a loss of its curvature at extreme muscle shortening.     

Modeling analysis of the relationship between atherosclerosis and related inflammatory factors

Objective: To establish early diagnosis model of inflammatory factors for atherosclerosis (AS), providing theoretical evidence for early detection of AS and development of plaques. Methods: Serum samples were collected to detect the inflammatory factors including CysC, Hcy, hs-CRP, UA, FIB, D-D, LP (a), IL-6, SAA, sCD40L and MDA. Using Logistic regression analysis, the inflammatory factors used for modeling were screened out, and then the AS early diagnosis models were established based on receiver operating characteristic (ROC) curve, support vector machine and BP neural network respectively. Results: No significant difference exists between the general materials of two groups. All 11 inflammatory factors had higher level in AS group than in control group. As shown in ROC curve, all inflammatory factors were helpful in AS diagnosis. In terms of sensitivity, UA ranked first (98) and FIB ranked last (55.5); in terms of specificity, UA ranked first (99) and FIB ranked last (78); in terms of area under the curve, UA and SAA ranked first (both were 0.995) and FIB ranked last (0.721). Based on Logistic regression equation, six factors were screened out, including Hcy, Hs-CRP, IL-6, D-D, CysC and MDA. According to classification, the final sixth steps had a prediction accuracy of 99%. When six inflammatory factors included in Logistic regression equation were detected jointly, the sensitivity, specificity and area under the curve were 57%, 97% and 0.821 respectively, while those of the model excluding D-D were 64%, 90% and 0.828, generally superior to results of joint detection including six factors. The ROC curve based on Hcy, Hs-CRP and MDA had a sensitivity of 87%, a specificity of 94% and an area under the curve of 0.869, being inferior to those of the ROC curve based on IL-6, D-D and Cys C, which were 87%, 92% and 0.936 respectively. The accuracy of SVM-AS diagnosis model and BP neural network model were 82.5% and 77.5% respectively. Conclusion: All 11 inflammatory factors are valuable in AS diagnosis. AS early diagnosis models based on Logistic regression analysis, ROC curve, support vector machine and BP neural network possess diagnostic value and can provide reference for clinical diagnosis.     

Direct yolk sac volume manipulation of zebrafish embryos and the relationship between offspring size and yolk sac volume

Through direct manipulation of yolk sac volume ( V _y), in the zebrafish Danio rerio , V _y and offspring size was positively correlated and the relationship was independent of geographical location, parental size or age and, most importantly, parental genetic factors. Larval survivorship, under a non-feeding regime and up until hatch, was not significantly affected by the manipulation. Decreased V _y significantly decreased maximum standard length ( L _S), maximum body surface area ( A _B), time to yolk sac absorption, L _S and A _B at yolk sac absorption, and the L _S and A _B at starvation. The methodology of V _y adjustment will be useful for the studies of the interaction between early life-history traits and offspring size, egg quality variables and early vertebrate development.     

The transient relationship between pressure and volume in the pediatric pulmonary system

An accurate understanding of the relationship between pulmonary pressure and volume is required for modeling pulmonary mechanics in a variety of clinical applications. In this study the experimental techniques and mathematical formulations used to characterize viscoelastic materials are applied to characterize transient pulmonary compliance in juvenile swine. Fixed volumes of air were insufflated into 5 swine and held constant for 45 s while the transient decay in tracheal pressure was measured. An analytical model was developed using an optimization scheme that maximized the model fit to the experimental data over the entire time convolution. The initial injected volume was varied to assess the spatial and temporal linearity of the behavior. Model performance was assessed by comparing measured and predicted pressure during insufflations of erratic volume waveforms. It is concluded that the pulmonary impedance of healthy juveniles can be adequately described over a wide volume and frequency range using a relatively simple 5-parameter model that is linear both spatially and temporally.     

Family income buffers the relationship between childhood adverse experiences and putamen volume

Adverse experiences and family income in childhood have been associated with altered brain development. While there is a large body of research examining these associations, it has primarily used cross-sectional data sources and studied adverse experiences and family income in isolation. However, it is possible that low family income and adverse experiences represent dissociable and potentially interacting profiles of risk. To address this gap in the literature, we examined brain structure as a function of adverse experiences in childhood and family income in 158 youths with up to five waves of MRI data. Specifically, we assessed the interactive effect of these two risk factors on six regions of interest: hippocampus, putamen, amygdala, nucleus accumbens, caudate, and thalamus. Adverse experiences and family income interacted to predict putamen volume (B = 0.086, p = 0.011) but only in participants with family income one standard deviation below the mean (slope estimate = −0.11, p = 0.03). These results suggest that adverse experiences in childhood result in distinct patterns of brain development across the socioeconomic gradient. Given previous findings implicating the role of the putamen in psychopathology-related behaviors, these results emphasize the importance of considering life events and socioeconomic context when evaluating markers of risk. Future research should include interactive effects of environmental exposures and family income to better characterize risk for psychopathology in diverse samples.     

Respiratory volume perception through the nose and mouth determined noninvasively

The relative importance of the nose vs. the mouth in the perception of respiratory volumes has never been assessed, nor have previous respiratory perception studies been performed noninvasively. Using respiratory inductive plethysmography, we monitored 12 normal subjects noninvasively when breathing either exclusively through the nose or mouth. The sensation of inspired volume mouth breathing was compared with that of nose breathing over a wide range of the inspiratory capacity. The psychophysical techniques of tidal volume duplication, tidal volume doubling, and magnitude estimation were utilized. A just noticeable difference was calculated from the constant error of the tidal volume duplication trials. The exponents for magnitude estimation were 1.06 and 1.07 for nose and mouth breathing, respectively. The other psychophysical techniques also revealed no differences in nose and mouth volume perception. These results suggest that tidal volume changes are perceived equally well through the nose and mouth. Furthermore, the location of the receptors, important in volume perception, is probably at a distal point common to the nose and mouth.     

Ristomycin effect on the relationship between electrokinetic parameters of erythrocytes and their volume

It was found that a decrease in the electrophoretic mobility of erythrocytes by the action of ristomycin reflects an increase in their volume.     

On the relationship between mouth opening and “broken mirror neurons” in autistic individuals

Electromyographies of the mylohyoid muscle (MH) during the execution of the goal-oriented action “grasping to eat” have been used to determine the time relationship between the opening of the mouth and the beginning of the movement. This has been used to distinguish the behaviour of typical developing (TD) children from that of highly functioning autistic (ASD) individuals. The results of previous studies appeared to provide evidence of a deficit in action chain organization in ASD subjects and prompted the hypothesis of a “broken” mirror neuron system (MNS) for these individuals. Our results show the MH activation timing is not reliable in discriminating between TD and ASD children and the distance between the food and the subject plays a key role on the MH activation timing and cannot be neglected when analysing these type of data. The preliminary investigation on the effects of external perturbations also shows that these might have an effect on the results and further investigations are warranted. It appears that there is not enough evidence to support a link between ASD and a broken mirror network system (MNS), and the experimental results must be carefully interpreted before developing therapeutic or rehabilitative protocols.     

急诊胸痛患者应激反应和应对方式的关系研究

目的探讨急诊胸痛患者应激反应和应对方式的水平及二者的相关性。方法选取2015年6月~2016年6月以胸痛为主诉到我院就诊的非外伤性胸痛患者300例,采用随机数字法分为对照组和实验组各150例,对照组为非绿色通道中的胸痛患者,实验组为绿色通道中的胸痛患者。两组患者均采用应激反应问卷(SRQ)评估患者的应激反应水平,医学应对问卷(MCMQ)评估患者应对方式水平,并进行组间比较,分析急诊胸痛患者应激反应和应对方式的相关性。结果 SRQ评分中,实验组患者行为反应维度明显高于对照组,差异具有统计学意义(P0.05);躯体反应维度明显低于对照组,差异具有统计学意义(P0.05)。MCMQ评分中,实验组患者屈服维度、回避维度及面对维度均高于对照组,差异具有统计学意义(P0.05)。急诊胸痛患者的应激反应和应对方式具有相关性,二者成正相关(P0.05)。结论急诊胸痛患者的应激反应和应对方式关系紧密,绿色通道中的胸痛患者应激反应和应对方式优于非绿色通道胸痛患者,绿色通道有助于急诊胸痛患者缓解应激反应,改善应对方式,加快患者康复进程。     

Fiddler crab (Crustacea: Ocypodidae) distribution and the relationship between habitat occupancy and mouth appendages

Sediment characteristics, especially grain size, are usually considered the most important variables affecting Uca distribution, mainly due to its close relationship with mouth appendage morphology. The aim of this study was to verify, from an assemblage perspective, if sediment is the most important variable affecting Uca species distribution, and if mouth appendage morphology (setae type and curvature) would be related to habitat occupancy. Niche metrics and null model approaches were used to assess and test the hypothesis. The relevance of spoon-tipped setae curvature to Uca distribution was verified for the first time. A fragmented mangrove area was divided into seven subareas, and sampling of crabs and environmental variables took place in June and November 2010. Of 10 species recorded for Brazil, seven were found in the study area: U. burgersi, U. cumulanta, U. leptodactyla, U. maracoani, U. rapax, U. thayeri and U. uruguayensis. Multivariate analysis showed that sediment grain size and the presence of vegetation were the most important variables explaining distribution, reinforcing results commonly obtained by univariate approaches. The overlap of habitat occupancy was generally low and no relationship between mouth appendages was found with breadth and overlap measures. Contrary to predictions, most non-random overlap values were lower than expected by chance, suggesting that interspecific competition might influence species distribution. Also, variables such as the presence of vegetation are important and influence crab distribution, limiting the potential distribution that would be predicted by mouth adaptations alone. Thus, the use of these adaptations as surrogates of fiddler crab distribution is not recommended.     

The relationship between DNA value and chromosome volume in the coleopteran genus Dermestes

DNA values and chromosome volumes were determined for six species of the coleopteran genus Dermestes which have very similar karyotypes. Large differences in DNA value occur which give no indication of a geometric series. DNA value is approximately proportional to chromosome volume, indicating that the DNA differences lie in the chromosomes. Evidence from the variation in volume of the sex chromosomes, along with the DNA values, cannot be interpreted in terms of a chromosome model with a variable number of strands. DNA values are often at variance with the taxonomic grouping of species within the genus.