New Findings
What is the central question of this study?
What is the impact of oxygen on the circulatory responses to an isocapnic cold pressor test (CPT) in lowlanders and Andean highlanders?
What ...is the main finding and its importance?
Overall, the circulatory responses to an isocapnic CPT were largely unaltered with acute normobaric hypoxia and chronic hypobaric hypoxia exposure in lowlanders. However, the relationship between mean arterial pressure and common carotid artery diameter was dampened in hypoxic conditions. Furthermore, there were no differences in the circulatory responses to the CPT between lowlanders and Andean highlanders with lifelong exposure to high altitude.
The impact of oxygen on the circulatory responses to a cold pressor test (CPT) in lowlanders and Andean highlanders remains unknown. Our hypotheses were as follows: (i) in lowlanders, acute normobaric and hypobaric hypoxia would attenuate the common carotid artery (CCA) diameter response to the CPT compared with normobaric normoxia; (ii) Andean highlanders would exhibit a greater CCA diameter response compared with lowlanders; and (iii) a positive relationship between CCA diameter and blood pressure in response to the CPT would be present in both lowlanders and highlanders. Healthy lowlanders (n = 13) and Andean highlanders (n = 8) were recruited and conducted an isocapnic CPT, which consisted of a 3 min foot immersion into water at 0–1°C. Blood pressure (finger photoplethysmography) and CCA diameter and blood flow (Duplex ultrasound) were recorded continuously. The CPT was conducted in lowlanders at sea level in isocapnic normoxic and hypoxic conditions and after 10 days of acclimatization to 4300 m (Cerro de Pasco, Peru) in hypoxic and hyperoxic conditions. Andean highlanders were tested at rest at high altitude. The main findings were as follows: (i) in lowlanders, normobaric but not hypobaric hypoxia elevated CCA reactivity to the CPT; (ii) no differences in response to the CPT were observed between lowlanders and highlanders; and (iii) although hypobaric hypoxaemia reduced the relationship between CCA diameter and blood pressure compared with normobaric normoxia (P = 0.132), hypobaric hyperoxia improved this relationship (P = 0.012), and no relationship was observed in Andean highlanders (P = 0.261). These data demonstrate that the circulatory responses to a CPT were modified by oxygen in lowlanders, but were unaltered with lifelong hypoxic exposure.
Adaptation genomics: the next generation Stapley, Jessica; Reger, Julia; Feulner, Philine G.D. ...
Trends in ecology & evolution (Amsterdam),
12/2010, Volume:
25, Issue:
12
Journal Article
Peer reviewed
Understanding the genetics of how organisms adapt to changing environments is a fundamental topic in modern evolutionary ecology. The field is currently progressing rapidly because of advances in ...genomics technologies, especially DNA sequencing. The aim of this review is to first briefly summarise how next generation sequencing (NGS) has transformed our ability to identify the genes underpinning adaptation. We then demonstrate how the application of these genomic tools to ecological model species means that we can start addressing some of the questions that have puzzled ecological geneticists for decades such as: How many genes are involved in adaptation? What types of genetic variation are responsible for adaptation? Does adaptation utilise pre-existing genetic variation or does it require new mutations to arise following an environmental change?
Abstract Plasma cortisol and behavior were measured in disbudded goat kids with and without the use of cornual nerve block. A total of 45 kids were used in 5 experimental groups (n = 9, males and ...females). Group LidoD was infiltrated with 1 mL of 2% lidocaine locally at the cornual branches of lacrimal and infratrochlear nerves, 15 min before thermal disbudding. Group Lido was similarly infiltrated and was not disbudded. In group Sim, the disbudding procedure was simulated. A control group (CD) was disbudded without lidocaine infiltration, and group SD was infiltrated with saline before disbudding. The cornual nerve block did not prevent the short-term increase in cortisol levels during and after disbudding. LidoD, CD and SD groups showed higher cortisol concentrations than Lido and Sim (p < 0.05) during the first 20 min after the procedure. Frequency of vocalizations during the procedure was significantly different between groups and was higher in SD (29.6 ± 3.1; mean ± SE) and CD (28.4 ± 3.1) than in Sim (16.6 ± 3.1; p < 0.05). Infiltrating lidocaine did not decrease this response to disbudding (21.1 ± 3.1; p > 0.05). Struggles tended to be higher in SD (16.5 ± 2.5), CD (17.8 ± 2.5) and LidoD (15.6 ± 2.5) than Sim (10.6 ± 2.5; p = 0.1). The total behavioral response was different between groups (CD, 59.6 ± 6.8; LidoD, 52 ± 6.8; SD, 62.6 ± 6.8; Sim, 36.8 ± 6.8; p = 0.05), and disbudded animals showed the strongest reactions (disbudded, 58.1 ± 3.9 vs non-disbudded, 36.8 ± 6.8; p = 0.01). It was concluded that cornual nerve block (lacrimal and infratrochlear) using 2% lidocaine did not prevent pain during thermal disbudding of goat kids.
The comparison of the solar heterogeneous photocatalysis (SHP) and solar photo Fenton (SPF) processes were carried out in a compound parabolic collector reactor, using methyl orange as a model ...pollutant, and the scaled-up parameters were estimated. As preliminary tests, both processes were carried out at laboratory scale (volume of 200 mL) and the accumulated energy (
Qv
) was registered to achieve high degradation and mineralization rates. The dye degradation by SHP in the solar reactor (volume of 30 L) was carried out using TiO
2
Degussa P25 until a
Qv
= 300 kJ m
−2
was reached. Under acidic condition, color removal of 95% and mineralization of 64% were achieved. The resulting reaction rates were
k
app
= 0.2311 L kJ
−1
and
k
app
= 0.0768 L kJ
−1
, respectively. On the other hand, dye degradation by SPF was faster than SHP since 99% color removal and 76.5% mineralization were achieved at
Qv
= 10 kJ m
−2
. Both processes were highly efficient in color removal and mineralization rates, at both scales. However, the SPF degradation was achieved at lower accumulated energy. The treatment capacity factor (
Ct
) required for the scaling-up of the solar reactor calculated for the SPF process is
Ct
= 6.41 kg
TOC
m
−2
y
−1
, and the area required for the treatment of a hypothetical textile effluent considering 1000 m
3
y
−1
and initial TOC of 800 mg L
−1
is 125 m
2
. These results suggest that SPF is an alternative of feasible implementation for the sanitation of textile effluents.
High-redshift (z > 2) blazars are the most powerful members of the blazar family. Yet, only a handful of them have both X-ray and γ-ray detection, thereby making it difficult to characterize the ...energetics of the most luminous jets. Here, we report, for the first time, the Fermi-Large Area Telescope detection of the significant γ-ray emission from the high-redshift blazar DA 193 (z = 2.363). Its time-averaged γ-ray spectrum is soft (γ-ray photon index = 2.9 0.1), and together with a relatively flat hard X-ray spectrum (14-195 keV photon index = 1.5 0.4), DA 193 presents a case to study a typical high-redshift blazar with inverse Compton peak being located at MeV energies. An intense GeV flare was observed from this object in the first week of 2018 January, a phenomenon rarely observed from high-redshift sources. What makes this event a rare one is the observation of an extremely hard γ-ray spectrum (photon index = 1.7 0.2), which is somewhat unexpected because high-redshift blazars typically exhibit a steep falling spectrum at GeV energies. The results of our multifrequency campaign, including both space- (Fermi, NuSTAR, and Swift) and ground-based (Steward and Nordic Optical Telescope) observatories are presented, and this peculiar γ-ray flare is studied within the framework of a single-zone leptonic emission scenario.
This paper presents a numerical model based on the Lattice Boltzmann Method (LBM), developed for studying dynamic responses of an unsaturated porous medium to periodic imbibition and drainage induced ...by a cyclic water table movement. The model includes gravity which helps defining an hydraulic head. The model predicted an incremental increase of the overall water content in the medium over each cycle prior to a quasi-steady oscillatory state, a hydraulic ratcheting effect that has been previously observed in laboratory experiments. An empirical model was proposed to combine the transient and harmonic variations of the volumetric water content. The parameters of this empirical model were examined against physical quantities including the frequency of the driving water table oscillations and the porosity of the porous medium. The findings presented here may help to improve the formulation of constitutive models that are able to describe hydraulic processes of unsaturated soils.
We compared the efficacy of continuous glucose monitoring (CGM) and point of care (POC) testing (standard of care) in assessing glycemic control in older adults with T2D treated with either basal ...insulin or insulin secretagogues plus sliding scale in long-term care facilities (LTCF). All 97 subjects underwent POC testing before meals and bedtime and wore a Dexcom CGM. Treatment adjustment was performed by the primary care team, with a target glucose of 140-180 mg/dL, and for a duration of intervention up to 60 days. Study endpoints included differences in hypoglycemia < 70 and 54 mg/dL and hyperglycemia > 180 and 250 mg/dL by POC and CGM. Participants baseline characteristics (age: 74.7±11 years, BMI: 29.6±7.9, HbA1c: 8.06±2.2%) admitted to skilled nursing care/subacute rehab (80%) or long-term care (20%) facilities with a median length of participation of 17 (interquartile range 11, 29) days. The mean daily glucose by POC was lower than CGM (171±45 vs. 188±45 mg/dL, p<0.01). CGM detected significant greater proportions of subjects with hypoglycemia <70 mg/dL (40% vs. 14%) and <54 mg/dL (21% vs. 1.0%); as well as hyperglycemia >250 mg/dL (77% vs. 56%) compared to POC testing, all p<0.001. Conclusion: In older adults with T2D admitted to long-term care facilities, the use of CGM significantly improved detection of hypoglycemic and hyperglycemic events compared to POC.
Disclosure
T.Idrees: None. T.M.Johnson: Consultant; Astellas Pharma Inc., Research Support; Dexcom, Inc. L.Peng: None. G.Umpierrez: Research Support; Abbott, Dexcom, Inc., Baxter. I.A.Castro-revoredo: None. M.D.Gavaller: None. H.Oh: None. Z.Zabala: None. E.M.Moreno: None. B.Moazzami: None. R.J.Galindo: Consultant; Novo Nordisk, Eli Lilly and Company, Sanofi, Pfizer Inc., Bayer Inc., WW (Weight Watchers), Research Support; Novo Nordisk, Eli Lilly and Company, Dexcom, Inc. E.Cabb: None.
Funding
Dexcom, Inc. (IIS-2020-119_6X)
The efficacy of real-time continuous glucose monitoring (rt-CGM) in adjusting insulin therapy in long-term care facilities (LTCF) has not been evaluated. Accordingly, we randomized 100 ...insulin-treated subjects with T2D in LTCF. All subjects underwent point-of-care (POC) capillary glucose testing before meals and bedtime. Patients in the standard of care (POC group) wore a blinded Dexcom G6 CGM with treatment adjusted based on POC results; while in the rt-CGM group (Dexcom G6), treatment adjustment was based on daily CGM profile. Treatment adjustment was performed by the LTC medical team, with a target glucose of 140-180 mg/dL, and a duration of intervention up to 60 days. Primary endpoint was difference between groups in time in range (TIR, 70-180 mg/dL). Results: There were no significant differences in TIR (53.38%±30.16 vs 48.81%±28.03, p=0.40), mean daily glucose (185±44 vs 191 ±47 mg/dL, p=0.72), patients with % CGM values <54 mg/dL (0.23±0.8% vs 0.56±2.2 %, p=0.88), with a trend in reducing time below range (TBR <70 mg/dL) (0.83±2.6 % vs 1.18±3.5%, p= 0.51), between CGM and POC group. Conclusion: The results of this pilot randomized study indicate that the use of Dexcom G6 rtCGM is safe and effective in guiding diabetes therapy in long-term care facilities, resulting in a similar improvement in glycemic control (TIR) without differences in hypoglycemia.
Disclosure
T.Idrees: None. T.M.Johnson: Consultant; Astellas Pharma Inc., Research Support; Dexcom, Inc. L.Peng: None. G.Umpierrez: Research Support; Abbott, Dexcom, Inc., Baxter. I.A.Castro-revoredo: None. H.Oh: None. M.D.Gavaller: None. Z.Zabala: None. E.M.Moreno: None. B.Moazzami: None. R.J.Galindo: Consultant; Novo Nordisk, Eli Lilly and Company, Sanofi, Pfizer Inc., Bayer Inc., WW (Weight Watchers), Research Support; Novo Nordisk, Eli Lilly and Company, Dexcom, Inc. E.Cabb: None.
Funding
Dexcom, Inc. (IIS-2020-119_6X)
Final-state kinematic imbalances are measured in mesonless production of νμ+A→μ-+p+X in the MINERvA tracker. Initial- and final-state nuclear effects are probed using the direction of the μ- - p ...transverse momentum imbalance and the initial-state momentum of the struck neutron. Differential cross sections are compared to predictions based on current approaches to medium modeling. These models underpredict the cross section at intermediate intranuclear momentum transfers that generally exceed the Fermi momenta. As neutrino interaction models need to correctly incorporate the effect of the nucleus in order to predict neutrino energy resolution in oscillation experiments, this result points to a region of phase space where additional cross section strength is needed in current models, and demonstrates a new technique that would be suitable for use in fine-grained liquid argon detectors where the effect of the nucleus may be even larger.
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