Waist Area Research Articles

Valve Wheel Rim Force Capabilities of Process Operators

The force that an operator is able to apply to a valve wheel depends on the location of the wheel and the orientation of the valve stem as well as the diameter of the wheel and the quality of the interface between the wheel and the hands. The objective of this study was to create a database that captured the maximum force that chemical and refinery workers can apply to crack open a valve equipped with a wheel actuator. Participants were 66 volunteer process operators and managers from a refinery and a chemical plant located on the Gulf Coast of the United States. Turning strength was measured by recording the force applied to the rim of the valve wheel during an isometric contraction in which there was no movement of the body. The data collected in this study clearly demonstrate a relationship between the posture of the operator, as defined by the height and orientation of the valve wheel, and the maximum turning force that can be applied. For a horizontal stem, the most force could be applied when the valve was in the knee or waist area. For vertical stem valves, operators appear to be able to apply the maximum force when the valve is located between the waist and the shoulder.

Differential projections to the intralaminar and gustatory thalamus from the parabrachial area: A PHA-L study in the rat

The organization of projections from the parabrachial (PB) area to the ventral posterior parvicellular (VPpc) "gustatory" and intralaminar nuclei of the thalamus was studied in the rat by using microinjections of Phaseolus vulgaris leucoagglutinin (PHA-L), into subregions of the PB area. The present study is a follow-up of three former studies (Bernard et al. [1993] J. Comp. Neurol. 329:201-229; Aldén et al. [1994] J. Comp. Neurol. 341:289-314; Bester et al. [1997a] J. Comp. Neurol. 383:245-281) that examined PB projections onto the amygdala, the bed nucleus of the stria terminalis, and the hypothalamus. Our data showed that (1) the region centered in the internal lateral PB subnucleus projects densely with a bilateral and symmetric pattern to the caudal portion of the paracentral and, to a lesser extent, to the adjacent portion of the central and parafascicular medial thalamic nuclei; (2) the mesencephalic PB region centered in the ventral lateral subnucleus and scattered neurons in the subjacent brachium conjunctivum project primarily, although diffusely, to the central medial thalamic nucleus. The third region includes two subgroups: (3a) the medial subgroup, including the medial, the waist area, and the ventral lateral subnuclei of the pontine PB area, projects bilaterally but with a weak ipsilateral predominance to the VPpc, terminals bearing large varicosities. Additionally, a diffuse projection with small varicosities spreads in the area between the two VPpc nuclei and the central medial nucleus. (3b) The lateral subgroup, centered in the external medial subnucleus, projects with a contralateral predominance in the periphery of the VPpc nuclei, most terminals being located around the dorsomedial tip. It is suggested that the PB projections to the intralaminar nucleus could be involved in cortical limbic arousal processing in relation with nociceptive, (somatic, visceral, and intraoral) and gustatory aversive stimuli. The projection with large varicosities inside the VPpc could process gustatory discrimination.

Differential projections to the intralaminar and gustatory thalamus from the parabrachial area: A PHA‐L study in the rat

The organization of projections from the parabrachial (PB) area to the ventral posterior parvicellular (VPpc) “gustatory” and intralaminar nuclei of the thalamus was studied in the rat by using microinjections of Phaseolus vulgaris leucoagglutinin (PHA-L), into subregions of the PB area. The present study is a follow-up of three former studies (Bernard et al. [1993] J. Comp. Neurol. 329:201–229; Aldén et al. [1994] J. Comp. Neurol. 341:289–314; Bester et al. [1997a] J. Comp. Neurol. 383:245–281) that examined PB projections onto the amygdala, the bed nucleus of the stria terminalis, and the hypothalamus. Our data showed that (1) the region centered in the internal lateral PB subnucleus projects densely with a bilateral and symmetric pattern to the caudal portion of the paracentral and, to a lesser extent, to the adjacent portion of the central and parafascicular medial thalamic nuclei; (2) the mesencephalic PB region centered in the ventral lateral subnucleus and scattered neurons in the subjacent brachium conjunctivum project primarily, although diffusely, to the central medial thalamic nucleus. The third region includes two subgroups: (3a) the medial subgroup, including the medial, the waist area, and the ventral lateral subnuclei of the pontine PB area, projects bilaterally but with a weak ipsilateral predominance to the VPpc, terminals bearing large varicosities. Additionally, a diffuse projection with small varicosities spreads in the area between the two VPpc nuclei and the central medial nucleus. (3b) The lateral subgroup, centered in the external medial subnucleus, projects with a contralateral predominance in the periphery of the VPpc nuclei, most terminals being located around the dorsomedial tip. It is suggested that the PB projections to the intralaminar nucleus could be involved in cortical limbic arousal processing in relation with nociceptive, (somatic, visceral, and intraoral) and gustatory aversive stimuli. The projection with large varicosities inside the VPpc could process gustatory discrimination. J. Comp. Neurol. 405:421–449, 1999. © 1999 Wiley-Liss, Inc.

Distribution of metabotropic glutamate receptors in the parabrachial and Kölliker–Fuse nuclei of the rat

In the present study, we analysed the distribution and cellular localization of metabotropic glutamate receptors (1 α, 2/3, 5) in parabrachial and Kölliker–Fuse nuclei using subtype-specific antisera. Immunolabelling revealed that different nuclei express different sets of metabotropic glutamate receptors. Metabotropic glutamate receptor 1 α immunoreactivity was found in the Kölliker–Fuse nucleus and in several parabrachial nuclei, including the waist area, lateral crescent, medial, external medial and ventral lateral nuclei. The external lateral and internal lateral parabrachial nuclei were devoid of metabotropic glutamate receptor 1 α immunoreactivity. Metabotropic glutamate receptor 5 immunoreactivity was observed in the Kölliker–Fuse and in the medial parabrachial nuclei, while in the remaining nuclei the staining was very weak. Again, the external lateral nucleus was devoid of metabotropic glutamate receptor 5 immunoreactivity. The metabotropic glutamate receptor 2/3 antisera stained all lateral parabrachial nuclei as well as the Kölliker–Fuse nucleus, while staining in the medial parabrachial nucleus was weak. Metabotropic glutamate receptor 1 α immunoreactivity was observed on presumed dendritic profiles, while metabotropic glutamate receptor 5 immunoreactivity was found predominantly on neuronal cell bodies. Metabotropic glutamate receptor 2/3 immunoreactivity was present as a fine, punctate immunostaining in the neuropil. Our data suggest that glutamate release in the parabrachial and Kölliker–Fuse nuclei might induce a variety of second messenger cascades, as indicated by the presence or absence of certain types of metabotropic glutamate receptors.

Differential projections from gustatory responsive regions of the parabrachial nucleus to the medulla and forebrain

The present study combined extracellular electrophysiology with anterograde and retrograde tracing techniques to determine efferent projections from taste responsive sites within the parabrachial nucleus (PBN). Taste activity was recorded from two distinct regions of the PBN, the waist region consisting of the ventrolateral (VL) and central medial (CM) subnuclei, and the external region, consisting of the external medial (EM) and external lateral (EL) subnuclei. Ascending and descending projections from these two regions differed. Small biotinylated dextran injections placed in taste responsive sites in the waist area produced a prominent descending projection to the medullary parvocellular reticular formation, a projection nearly non-existent from the external region. Differences in ascending projections were more subtle. Projections to the thalamus were bilateral in all cases, however, the waist region had a larger ipsilateral thalamic projection than the external region and the external region had a larger contralateral projection compared to the waist. Central nucleus of amygdala (CNA) projections from the waist area were primarily from posterior tongue responsive sites in VL and terminated in the central medial and lateral CNA subnuclei; external region projections were distributed to the capsular region of CNA. Both the external and waist region projected to substantia innominata (SI). Different efferent projections from the two gustatory responsive regions of the PBN may reflect functional specialization of PBN subnuclei. Descending projections from orally responsive sites in the waist area project to the lateral parvocellular reticular formation, a region implicated in brainstem circuitry underlying consummatory components of ingestive function. The external region, contains cells responsive to pain and oral aversive stimuli, but does not apparently contribute directly to local brainstem functions. Rather, forebrain pathways appear critical to the expression of external region functions.

GABA, GABA transporters, GABAAreceptor subunits, and GAD mRNAs in the rat parabrachial and Kölliker‐Fuse nuclei

In the present study, we investigated the key molecules that determine γ-aminobutyric acid (GABA)ergic signal transduction in the parabrachial/Kölliker-Fuse complex (PB/KF) by means of immunocytochemistry and in situ hybridization. Our data demonstrate a dense plexus of GABA-immunoreactive (-ir) varicosities throughout the nuclei of the PB and the KF. The number of neurons expressing GAD65 or GAD67 mRNA was fairly low in the PB, whereas caudally in the KF an accumulation of GAD-expressing neurons was observed. The GABA transporter-3 (GAT-3) was detected in all parts of the PB/KF, whereas immunolabeling for GAT1 was not observed. All nuclei of the PB and the KF exhibited immunoreactivity for the γ2-, α2-, and α3-subunits of the GABAA receptor. γ2-ir was strong and similar in all PB/KF nuclei. In contrast, α2-labeling was particularly intense in the superior lateral PB, and α3-labeling was most prominent in the external lateral and external medial PB, compared with the remaining nuclei. With respect to the subcellular localization, we found γ2-ir in cell bodies and higher order dendrites, whereas α2- and α3-ir was predominantly found in cell bodies. Immunolabeling for the β2/3- and the α1-subunit was seen in cell bodies and presumed dendritic profiles. The staining intensity was strongest in the dorsal lateral PB. Most importantly, the external lateral PB and the waist area were totally devoid of β2/3- and α1-ir. Our data suggest that neural processing in the PB/KF is under a strong GABAergic inhibition that is apparently mediated by different types of GABAA receptors in functionally different pathways through the PB/KF. J. Comp. Neurol. 400:229–243, 1998. © 1998 Wiley-Liss, Inc.

GABA, GABA transporters, GABAAreceptor subunits, and GAD mRNAs in the rat parabrachial and K�lliker-Fuse nuclei

In the present study, we investigated the key molecules that determine gamma-aminobutyric acid (GABA)ergic signal transduction in the parabrachial/Kölliker-Fuse complex (PB/KF) by means of immunocytochemistry and in situ hybridization. Our data demonstrate a dense plexus of GABA-immunoreactive (-ir) varicosities throughout the nuclei of the PB and the KF. The number of neurons expressing GAD65 or GAD67 mRNA was fairly low in the PB, whereas caudally in the KF an accumulation of GAD-expressing neurons was observed. The GABA transporter-3 (GAT-3) was detected in all parts of the PB/KF, whereas immunolabeling for GAT1 was not observed. All nuclei of the PB and the KF exhibited immunoreactivity for the gamma2-, alpha2-, and alpha3-subunits of the GABA(A) receptor. Gamma2-ir was strong and similar in all PB/KF nuclei. In contrast, alpha2-labeling was particularly intense in the superior lateral PB, and alpha3-labeling was most prominent in the external lateral and external medial PB, compared with the remaining nuclei. With respect to the subcellular localization, we found gamma2-ir in cell bodies and higher order dendrites, whereas alpha2- and alpha3-ir was predominantly found in cell bodies. Immunolabeling for the beta2/3- and the alpha1-subunit was seen in cell bodies and presumed dendritic profiles. The staining intensity was strongest in the dorsal lateral PB. Most importantly, the external lateral PB and the waist area were totally devoid of beta2/3- and alpha1-ir. Our data suggest that neural processing in the PB/KF is under a strong GABAergic inhibition that is apparently mediated by different types of GABA(A) receptors in functionally different pathways through the PB/KF.

Protective overalls: evaluation of garment design and fit

Protective clothing should ideally provide maximum comfort and protection for the wearer. The design and fit of a garment are factors which can affect both the protective aspects of a garment as well as its comfort. Proper garment fit depends on the relationship of the size of the garment compared with the size of the wearer. Garment ease (where the garment is larger than the wearer) should allow for comfort and mobility; both too much or too little ease can result in a garment that is uncomfortable and restrictive to movement. The purpose of this study was to explore a research technique to isolate the effects of garment ease in one area of a garment while ease in all other garment areas was controlled, and to determine a design that would maximize wearer mobility. Using five male subjects, protective overalls with differing amounts and garment location of crotch ease were evaluated for their effects on mobility and wearer acceptance. Range of motion measurements for selected joints were evaluated using a Leighton Flexometer. Subjects completed a subjective evaluation scale after performing an exercise protocol while wearing the overalls. Results indicated that a specific amount of ease in the crotch length of overalls may be appropriate. Additionally, an overall design that had all needed crotch ease in the back waist area of the garment may be desirable over the more conventional method of adding ease evenly between the front and back sections of the garment. The methodology used in this study provides a means of evaluating not only the potential for design variations in protective clothing, but provides a means to evaluate the dynamic aspects of fit of clothing.

The effects of air mattress upon sleep and bed climate.

The purpose of this study was to investigate the effects of an air mattress upon sleep and bed climate. This air mattress, which employs a pump and timer to increase or decrease the inflation pressure in order to cure and prevent decubitus was tested. Six healthy female volunteers, aged 18 to 23, served as subjects. The experiments were carried out under three conditions: using regular Futon (Futon), the air mattress with pump and timer activated (Air+) and the same mattress without pump and timer activated (Air-). Room temperature and relative humidity were controlled at 22-23 degrees C and RH 50-60% respectively. Subjects' sleep was monitored by using EEG machine throughout the night, and subject's body temperature and bed climate were also continuously checked. Subjective estimation of bed and sleep were obtained before and after the recording sessions. Sleep onset latency and wake after sleep onset tended to be reduced in Air+ compared to Futon and Air-. The time and percentage of Stage 3 was increased significantly in the middle one third of the night in Air+. A significant difference was observed in bed climate of the waist area. Temperature tended to be higher in Futon than in Air+ and Air-, while relative and absolute humidity were significantly higher in Air+ and Air-. Significant difference between Air+ and Air- was observed only during one hour after sleep recordings started. Thermal sensation in the morning was cooler and comfort sensation tended to be better in Air+ and Air-. Subjective sleep estimation was somewhat good under all conditions. These results suggest that although these air mattresses do not affect sleep, we have to be cautious in using these mattresses as relative and absolute humidity were kept higher than with Futon. Further study on materials and construction of these air mattresses to decrease the humidity is needed.

The effects of a newly designed air mattress upon sleep and bed climate.

In our previous study, an air mattress with three series of air cells with inflation pressure, that was increased/decreased in time interval of 20 min, did not affect sleep quality and quantity, although the relative and absolute humidity inside the bedding was kept significantly higher than that of a Futon. The purpose of this study was to confirm the effects of a newly designed air mattress upon sleep and bed climate. In this newly designed air mattress, the cell series and time interval was reduced. Six healthy female volunteers, aged 18-22, served as subjects. The experiment was carried out under two conditions: using a regular Futon (Futon), and a newly-designed air mattress with the timer and pump activated (Airmat). The room temperature and relative humidity were controlled at 22-23 degrees C and RH 50-60%, respectively. The subjects' sleep was monitored by using an EEG machine and their skin temperatures and bed climates were also measured continuously. Subjective evaluations of bed comfort and sleep were obtained before and after the recording sessions. Sleep onset latency, wake after sleep onset and the sleep efficiency index showed no significant differences between the two conditions. A significant difference was observed in the bed climate of the waist area. The temperature of the waist was lower overall under the Airmat than the Futon, while relative humidity was higher under the Airmat. Absolute humidity also tended to be higher in the Airmat. Sleep evaluation and comfort sensation were good under both conditions. Although sleep was not disturbed and subjective sleep evaluation tended to be better in Airmat, our results indicate that changing the time intervals and cell series until this air mattress level is not effective in decreasing the bed climate humidity.

Far-field diffraction of truncated higher-order Laguerre-Gaussian beams

A simple analytic expression for the far-field diffraction pattern of a general high-order Laguerre-Gaussian mode from a circular aperture is derived. Aperturing of the fundamental Gaussian beam is shown as a special case, where in the limit of waist size much larger than the aperture the Airy pattern is recovered and in the opposite limit we get a Gaussian intensity pattern. The diffraction pattern is shown to be an infinite series of Bessel functions and is strongly dependent on the ratio of the aperture area to the beam waist area (also known as the truncation parameter). This formulation leads to a more intuitive understanding of the far field of these modes, and the effect of the aperture as a spatial filter is discussed.

Distribution of alpha 2-adrenergic binding sites in the parabrachial complex of the rat.

The present study describes the distribution of alpha 2-adrenoceptors in the parabrachial and Kölliker-Fuse nucleus of the rat by employing the tritium-labeled alpha 2-receptor antagonist rauwolscine ([3H]-RAUW) as a ligand. The [3H]-RAUW binding was densitometrically quantified in five nuclei of the parabrachial (PB) complex in serial coronal sections. We found that cytoarchitectonically and anatomically distinct nuclei of the PB complex exhibit different numbers of [3H]-RAUW-binding sites. The largest number of binding sites was observed over the external lateral PB and caudally over the waist area of the PB. Lower numbers of binding sites were found in the remaining lateral PB nuclei, followed by the medial PB and the Kölliker-Fuse nucleus. In addition we disclosed that the internal lateral PB contains a very low number of binding sites while the external medial PB is marked by dense [3H]-RAUW binding. Also, the affinities of the binding sites differed between the PB areas. High affinities were observed in the external lateral PB, the remaining lateral PB nuclei and in the waist area of the PB, while the medial PB and the Kölliker-Fuse nucleus exhibited only low affinities for the ligand. Furthermore, saturation curves demonstrated non-linear profiles, indicating the presence of more than one population of binding sites in the PB nuclei for the radioligand. Our data demonstrate that the PB exhibits a distinct distribution of alpha 2-adrenergic binding sites. These correlate well with the cytoarchitectonically defined nuclei of the PB complex and with the pattern of ascending axons from the medial nucleus of the solitary tract and the area postrema terminating in the PB. Since a large number of these projection neurons utilize adrenaline or noradrenaline as their transmitters, we conclude that solitary-parabrachial neurotransmission to the forebrain is, at least in part, mediated via alpha 2-adrenoceptors.

The organization of the efferent projections from the pontine parabrachial area to the amygdaloid complex: a Phaseolus vulgaris leucoagglutinin (PHA-L) study in the rat.

The organization of the efferent projections from the pontine parabrachial (pPB) area to the amygdala has been studied in the rat by using microinjections of Phaseolus vulgaris leucoagglutinin (PHA-L), a sensitive and selective anterograde axonal marker, into restricted subregions of the pPB area. The results confirmed that the pPB area primarily projected onto the ipsilateral nucleus centralis of the amygdala (Ce), and to a lesser extent onto the ipsilateral posterior basolateral (BLP), anterior basomedial (BMA), and amygdaloid cortical (ACo) nuclei of the amygdala. Substantial projections were also found in the substantia innominata dorsal/ventral portion of the globus pallidus (SId/GPv), substriatal (SStr), and fondus striatal (FStr) regions which continue the amygdala rostrally. The results demonstrated that the projections of the pPB area onto the Ce were topically organized: 1) The region of the pPB area mainly including the medial subnucleus (pPBm), the waist area (pPBwa), and a thin rostral lamina of the ventral lateral subnucleus (pPBvl) projects primarily to the medial portion of the Ce (CeM). Dense projections were also found in the BLP, BMA, and ACo nuclei of the amygdala, and in the SId/GPv, SStr, and FStr rostral areas. 2) The region of the pPB mainly including the rostral portion of the central lateral subnucleus (pPBcl) and the outer-rostral portion of the external lateral subnucleus (pPBel) projects primarily to the lateral portion of the Ce (CeL). 3) The region of the pPB mainly including the dorsolateral subnucleus (pPBdl), the remaining pPBel, and the external medial (pPBem) subnuclei projects primarily to the lateral capsular portion of the Ce (CeLC) and bilaterally to its rostral portion. Dense projections were also found in the regions which extend the CeLC rostrally and in the SId/GPv, SStr, and FStr rostral areas. The possible role of each of the three parabrachio-amygdaloid pathways described is discussed. It was suggested that the pPB-CeM pathway is mainly implicated in gustatory processes; the pPB-CeL pathway is mainly implicated in visceral and chemosensitive processes; and the pPB-CeLC pathway is mainly implicated in respiratory, cardiovascular, and nociceptive processes.

The Waxing and Waning of Relational Intimacy: Touch as a Function of Relational Stage, Gender and Touch Avoidance

Scholars have paid increasing attention to the role of non-verbal communication within intimate relationships. Reportedly, immediate behaviors such as touch escalate opposite-sex relationships by promoting increased intimacy and psychological closeness. This study examined the effects of relational stage, gender and touch avoidance on unobtrusively coded public touch behavior. An ANOVA indicated that relational stage was curvilinearly related to public interpersonal touch such that the level of touch was higher in intermediate stage of relationships than in either initial or stable stages. Gender had no effect on touch. Instead, a high correlation was found between the amount of touch used by males and the amount of touch used by their female partners. Touch avoidance was found to be linearly related to the amount of touch displayed, with low touch avoiders touching the most and high touch avoiders touching the least. There was a strong additive effect for touch avoidance, with all three touch avoidance groups following a curvilinear pattern for relational stage. x2 tests found that touch increased primarily in the hand and waist areas during the intermediate stage. Implications for the study of reciprocity, immediacy, intimacy and stage theory are discussed.

Organization of cortical, basal forebrain, and hypothalamic afferents to the parabrachial nucleus in the rat

In a previous study (Herbert et al., J. Comp. Neurol. [1990];293:540-580), we demonstrated that the ascending afferent projections from the medulla to the parabrachial nucleus (PB) mark out functionally specific terminal domains within the PB. In this study, we examine the organization of the forebrain afferents to the PB. The PB was found to receive afferents from the infralimbic, the lateral prefrontal, and the insular cortical areas; the dorsomedial, the ventromedial, the median preoptic, and the paraventricular hypothalamic nuclei; the dorsal, the retrochiasmatic, and the lateral hypothalamic areas; the central nucleus of the amygdala; the substantia innominata; and the bed nucleus of the stria terminalis. In general, forebrain areas tend to innervate the same PB subnuclei from which they receive their input. Three major patterns of afferent termination were noted in the PB; these corresponded to the three primary sources of forebrain input to the PB: the cerebral cortex, the hypothalamus, and the basal forebrain. Hypothalamic afferents innervate predominantly rostral portions of the PB, particularly the central lateral and dorsal lateral subnuclei. The basal forebrain projection to the PB ends densely in the external lateral and waist subnuclei. Cortical afferents terminate most heavily in the caudal half of the PB, particularly in the ventral lateral and medial subnuclei. In addition, considerable topography organization was found within the individual projections. For example, tuberal lateral hypothalamic neurons project heavily to the central lateral subnucleus and lightly to the waist area; in contrast, caudal lateral hypothalamic neurons send a moderately heavy projection to both the central lateral and waist subnuclei. Our results show that the forebrain afferents of the PB are topographically organized. These topographical differences may provide a substrate for the diversity of visceral functions associated with the PB.

An improved astigmatically compensated resonator for CW dye lasers

An improved resonator configuration for CW dye lasers is described, permitting minimum circular waist areas and compensation for comatic as well as astigmatic aberration.