938 research outputs found
Acu-TENS and Postexercise Expiratory Flow Volume in Healthy Subjects
Transcutaneous Electrical Nerve Stimulation over acupoints (Acu-TENS) facilitates recovery of resting heart rate after treadmill exercise in healthy subjects. Its effect on postexercise respiratory indices has not been reported. This study investigates the effect of Acu-TENS on forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in healthy subjects after a submaximal exercise. Eleven male subjects were invited to the laboratory twice, two weeks apart, to receive in random order either Acu-TENS or Placebo-TENS (no electrical output from the TENS unit) over bilateral Lieque (LU7) and Dingchuan (EX-B1) for 45 minutes, before undergoing exercise following the Bruce protocol. Exercise duration, rate of perceived exertion (RPE), and peak heart rate (PHR) were recorded. Between-group FEV1 and FVC, before, immediately after, at 15, 30, and 45minutes postexercise, were compared. While no between-group differences in PHR, RPE, and FVC were found, Acu-TENS was associated with a longer exercise duration (0.9 min (P = .026)) and a higher percentage increase in FEV1 at 15 and 45 minutes postexercise (3.3 ± 3.7% (P = .013) and 5.1 ± 7.5% (P = .047), resp.) compared to Placebo-TENS. We concluded that Acu-TENS was associated with a higher postexercise FEV1 and a prolongation of submaximal exercise
The Role of Acu-TENS in Hemodynamic Recovery after Open-Heart Surgery
Increased heart rate (HR) and reduced blood pressure (BP) are common consequences of cardiac surgery. This study investigated the effect of transcutaneous electrical nervous stimulation applied over acupuncture points (Acu-TENS) on HR, BP, rate pressure product (RPP) and nausea and vomiting score after open-heart surgery. After open heart surgery, 40 patients were randomly allocated to either an Acu-TENS group, which received a 40-min session of TENS applied bilaterally over the acupuncture point PC6 on postoperative days 1–5, or a Placebo-TENS group, which received identical electrode placement but with no electrical output from the TENS unit, despite an output indicator light appearing activated. HR, systolic and diastolic BPs (SBP and DBP) were recorded and RPP computed. Nausea and vomiting symptoms were quantified using a 4-point Likert scale before and after TENS intervention. Daily HR, BP and antiemetic administration data were recorded from a further 20 consecutive subjects who received no intervention and formed the Control group. A trend of decreasing HR and increasing BP in the Acu-TENS group was observed over the five postoperative days, with all variables returning to preoperative values by Day 4 (P > .2). In the Placebo-TENS and Control groups the HR remained higher (P < .0001), BP lower (P < .05) and RPP higher (P = .01) than respective preoperative values at Day 4. The dose of Maxolon required was lowest in the Acu-TENS group (P = .038). We concluded that Acu-TENS facilitated an earlier return to preoperative BP, HR and RPP values in patients after acute heart surgery
Predicting aflatoxin content in peanuts using ambient temperature, soil temperature and soil moisture content during pod development
Higher than acceptable aflatoxin levels in peanut kernels (Arachis hypogaea L.) and related products is
a worldwide food safety concern. Strict regulatory standards by major importers of peanuts limit the
marketability of peanuts for many developing tropical countries including Zambia. The incidence of preharvest
aflatoxins is strongly linked to soil and weather conditions during pod-development. This study
aimed to formulate statistical models to predict total aflatoxin content in peanut kernels using selected
environmental factors during pod development. Field experiments were conducted for two years during
which the peanut crop was exposed to 84 combinations of ambient temperature, soil temperature and
soil moisture content measured during the last 30 days of pod development. These data were used to
formulate regression models to predict total aflatoxin content in peanut kernels. Simple linear
regression models had R2 values of 0.30 for maximum ambient temperature, 0.24 for soil temperature
and 0.38 for soil moisture content. Combining soil moisture content and soil temperature in a
multivariate regression model could explain 54% of the variation in total aflatoxin content while a
combination of soil moisture content and maximum ambient temperature could only explain 46% of the
variation in total aflatoxin content
Acu-TENS Reduces Breathlessness during Exercise in People with Chronic Obstructive Pulmonary Disease
Background. Exertional dyspnoea limits level of physical activity in people with Chronic Obstructive Pulmonary Disease (COPD). This randomized, double-blinded, crossover study evaluated the effect of Acu-TENS, application of Transcutaneous Electrical Nerve Stimulation on acupoints, on breathlessness during exercise in people with COPD. Methods. Twenty-one participants, mean% predicted FEV1 50±21%, attended assessment followed by two intervention days, one week apart. On each intervention day, participants performed two endurance shuttle walk tests (ESWT) (Walk 1 and Walk 2). Walk 1 was performed without intervention and Walk 2 was performed with either Acu-TENS or Sham-TENS, in random order, for 45 minutes before and during Walk 2. Duration of each ESWT and dyspnoea score at isotime of Walk 1 and Walk 2 on each intervention day were compared. Between-group differences in ESWT duration and isotime dyspnoea were also compared. Results. At isotime of Walk 1 and Walk 2, Acu-TENS showed significant reduction in dyspnoea of −0.8 point (95% CI −0.2 to −1.4) but not in Sham-TENS [0.1 point (95% CI −0.4 to 0.6)]. Compared to Sham-TENS, Acu-TENS showed significant reduction in dyspnoea of −0.9 point (95% CI −0.2 to −1.6) while no between-group significance was found in ESWT duration. Conclusion. Acu-TENS alleviated dyspnoea during walking in people with COPD but did not increase walking duration
Full polar cap cascade scenario: -ray and X-ray luminosities from spin-powered pulsars
We modify polar cap cascade picture to include the ICS of the higher
generation pairs. In such a ``full-cascade'' scenario, not only the
perpendicular portion of the energy of the pairs goes to high energy radiation
via SR, but the parallel portion of the energy of the pairs can also contribute
to high energy emission via ICS with the soft thermal photons from either the
full neutron star surface or the hot polar cap. An important output of such a
scenario is that the soft tail of the ICS spectrum can naturally result in a
non-thermal X-ray component which can contribute to the luminosities observed
by ROSAT and ASCA. Here we present an analytic description of such a full polar
cap cascade scenario within the framework of Harding & Muslimov acceleration
model. We present the theoretical predictions of the -ray luminosities,
the thermal and non-thermal X-ray luminosities for the known spin-powered X-ray
pulsars. Our results show that the observed different dependences of the high
energy luminosities on the pulsar spin-down luminosities, i.e., and , are well
reproduced. Our model predicts that the {\em pulsed} soft X-rays in the ROSAT
band from most of the millisecond pulsars might be of thermal origin if there
is no strong multipole field components near the surfaces of these pulsars.Comment: 23 pages, emulateapj style, final version to appear in the
Astrophysical Journa
The effects of gypsum on pod-yield and pre-harvest aflatoxin contamination in selected peanut cultivars of Zambia
Good agricultural practices are an effective means of minimizing pre-harvest aflatoxin contamination in peanuts. A field experiment was conducted to evaluate the effect of gypsum on pod yield and aflatoxin contamination in three peanut cultivars (Kadononga, MGV 4 and MGV 5) in Zambia. The experiment was conducted in Chongwe and Lusaka districts. Gypsum (15.6 % calcium) was applied at rates of 0 and 400 kg/ha at flowering stage. Although gypsum had no significant effect on aflatoxin contamination, there were significant differences (p = 0.009) in cultivar susceptibility to aflatoxin contamination. The cultivar with the smallest kernels had 18.8% lower aflatoxin content than the large-kernelled cultivar. Additionally, gypsum did not have a clear effect on pod yield. For instance, gypsum was associated with 44.8% more grain-filled pods in Kadononga (p = 0.005) at the site in Lusaka, but this result did not apply to the other two cultivars. At the site in Chongwe, gypsum was associated with 34.6% higher pod yield of MGV 5 only (p = 0.006). These results further suggest that plant factors such as kernel size may have an influence on natural resistance to aflatoxin contamination in peanuts
Particle Acceleration Zones Above Pulsar Polar Caps: Electron and Positron Pair Formation Fronts
We investigate self-consistent particle acceleration near a pulsar polar cap
(PC) by the electrostatic field due to the effect of inertial frame dragging.
Test particles gain energy from the electric field parallel to the open
magnetic field lines and lose energy by both curvature radiation (CR) and
resonant and non-resonant inverse Compton scattering (ICS) with soft thermal
X-rays from the neutron star (NS) surface. Gamma-rays radiated by electrons
accelerated from the stellar surface produce pairs in the strong magnetic
field, which screen the electric field beyond a pair formation front (PFF).
Some of the created positrons can be accelerated back toward the surface and
produce gamma-rays and pairs that create another PFF above the surface. We find
that ICS photons control PFF formation near the surface, but due to the
different angles at which the electron and positron scatter the soft photons,
positron initiated cascades develop above the surface and screen the
accelerating electric field. Stable acceleration from the NS surface is
therefore not possible in the presence of dominant ICS energy losses. However,
we find that stable acceleration zones may occur at some distance above the
surface, where CR dominates the electron and positron energy losses, and there
is up-down symmetry between the electron and positron PFFs. We examine the
dependence of CR-controlled acceleration zone voltage, width and height above
the surface on parameters of the pulsar and its soft X-ray emission. For most
pulsars, we find that acceleration will start at a height of 0.5 - 1 stellar
radii above the NS surface.Comment: 46 pages, 12 embedded figures, accepted for publication in Ap
Palliative care professionals’ perceptions of barriers and challenges to accessing children’s hospice and palliative care services in South East London: A preliminary study
Objectives:
Several barriers have been identified as preventing or delaying accessing to children’s palliative care services. The aim of this study is to further explore such barriers from palliative care professionals’ perspective from two London boroughs.
Methods:
Qualitative- five children’s palliative care professionals perceptions obtained from semi-structured interviews.
Results:
Three themes emerged: availability and adequacy of child palliative care (e.g., unreliability of services), obstacles to accessing palliative care (e.g., logistical challenges) and cultural values and family priorities.
Conclusion:
These findings contribute to the equal opportunities dialogue in this sector and the need for future research to address the challenges identified
Orexinergic Input to Dopaminergic Neurons of the Human Ventral Tegmental Area
The mesolimbic reward pathway arising from dopaminergic (DA) neurons of the ventral tegmental area (VTA) has been
strongly implicated in reward processing and drug abuse. In rodents, behaviors associated with this projection are
profoundly influenced by an orexinergic input from the lateral hypothalamus to the VTA. Because the existence and
significance of an analogous orexigenic regulatory mechanism acting in the human VTA have been elusive, here we
addressed the possibility that orexinergic neurons provide direct input to DA neurons of the human VTA. Dual-label
immunohistochemistry was used and orexinergic projections to the VTA and to DA neurons of the neighboring substantia
nigra (SN) were analyzed comparatively in adult male humans and rats. Orexin B-immunoreactive (IR) axons apposed to
tyrosine hydroxylase (TH)-IR DA and to non-DA neurons were scarce in the VTA and SN of both species. In the VTA,
15.062.8% of TH-IR perikarya in humans and 3.260.3% in rats received orexin B-IR afferent contacts. On average, 0.2460.05 and 0.0560.005 orexinergic appositions per TH-IR perikaryon were detected in humans and rats, respectively. The majority(86–88%) of randomly encountered orexinergic contacts targeted the dendritic compartment of DA neurons. Finally, DA neurons of the SN also received orexinergic innervation in both species. Based on the observation of five times heavierorexinergic input to TH-IR neurons of the human, compared with the rat, VTA, we propose that orexinergic mechanism acting in the VTA may play just as important roles in reward processing and drug abuse in humans, as already established
well in rodents
The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets
This review addresses our current understanding of comets that venture close to the Sun, and are hence exposed to much more extreme conditions than comets that are typically studied from Earth. The extreme solar heating and plasma environments that these objects encounter change many aspects of their behaviour, thus yielding valuable information on both the comets themselves that complements other data we have on primitive solar system bodies, as well as on the near-solar environment which they traverse. We propose clear definitions for these comets: We use the term near-Sun comets to encompass all objects that pass sunward of the perihelion distance of planet Mercury (0.307 AU). Sunskirters are defined as objects that pass within 33 solar radii of the Sun’s centre, equal to half of Mercury’s perihelion distance, and the commonly-used phrase sungrazers to be objects that reach perihelion within 3.45 solar radii, i.e. the fluid Roche limit. Finally, comets with orbits that intersect the solar photosphere are termed sundivers. We summarize past studies of these objects, as well as the instruments and facilities used to study them, including space-based platforms that have led to a recent revolution in the quantity and quality of relevant observations. Relevant comet populations are described, including the Kreutz, Marsden, Kracht, and Meyer groups, near-Sun asteroids, and a brief discussion of their origins. The importance of light curves and the clues they provide on cometary composition are emphasized, together with what information has been gleaned about nucleus parameters, including the sizes and masses of objects and their families, and their tensile strengths. The physical processes occurring at these objects are considered in some detail, including the disruption of nuclei, sublimation, and ionisation, and we consider the mass, momentum, and energy loss of comets in the corona and those that venture to lower altitudes. The different components of comae and tails are described, including dust, neutral and ionised gases, their chemical reactions, and their contributions to the near-Sun environment. Comet-solar wind interactions are discussed, including the use of comets as probes of solar wind and coronal conditions in their vicinities. We address the relevance of work on comets near the Sun to similar objects orbiting other stars, and conclude with a discussion of future directions for the field and the planned ground- and space-based facilities that will allow us to address those science topics
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