negative slope
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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Xue Tian ◽  
Anxin Wang ◽  
Yingting Zuo ◽  
Shuohua Chen ◽  
Licheng Zhang ◽  
...  

Abstract Background The impact of long-term serum uric acid (SUA) exposure and time course of SUA accumulation on diabetes mellitus (DM) is unknown. This study aimed to evaluate the association of cumulative SUA (cumSUA) exposure and its accumulation time course with risk of DM. Methods This prospective study included 46,434 participants without DM and underwent three examinations at 2006, 2008, and 2010. CumSUA from 2006 to 2010 was calculated, multiplying mean values between consecutive examinations by time intervals between visits. Time course of SUA accumulation was categorized as the slope of SUA versus time from 2006 to 2010, or by splitting the overall accumulation into an early (cumSUA06-08) and late accumulation (cumSUA08-10). Results During 6.99 years of follow-up, we identified 2971 incident DM cases. In the fully adjusted model, a higher risk of DM was observed in participants with the highest quartile of cumSUA (hazard ratio [HR], 1.31; 95% confidence interval [CI], 1.17–1.46), cumulative burden >0 (HR, 1.23; 95% CI, 1.08–1.40), and with 6 year of hyperuricemia exposure duration (HR, 1.25; 95% CI, 1.01–1.55). When considering the time course of SUA accumulation, participants with a negative slope (HR, 1.05; 95% CI, 1.01–1.12), or combined with cumSUA ≥ median and a negative slope had elevated risk of DM (HR, 1.58; 95% CI, 1.18–2.11). Conclusions Incident DM risk depends on cumulative exposure of SUA and time course of SUA accumulation. Early SUA accumulation resulted in a greater risk increase compared with later accumulation, emphasizing the importance of optimal SUA control early in life.


2021 ◽  
Vol 26 (2) ◽  
pp. 119-126
Author(s):  
Sujan Prasad Gautam ◽  
Ashok Silwal ◽  
Mijas Tiwari ◽  
Seema Subedi ◽  
Manish Khanal ◽  
...  

We studied the dust properties of two cavity structures (namely FIC21+54 and FIC16-56) nearby Asymptotic Giant Branch stars using Infrared Astronomical Satellite (IRAS) maps. Dust color temperature, Planck function, dust mass, and visual extinction with their distribution within the region of interest were examined. The temperature of dust was found to lie in the range of 22.24 ± 0.81 K to 23.27 ± 0.21 K, and 25.12 ± 0.43 K to 26.17 ± 0.62 K, and the mass of dust was obtained within the range of 4.21 × 1026 kg to 3.6 × 1027 kg, and 2.1 × 1027 kg to 3.31 × 1028 kg, for FIC21+54 and FIC16-56, respectively. Some unusual behaviors on the distribution of dust temperature indicated the effect of nearby sources within the studied structures. Moreover, we observed the trend of dust particles along the major and minor diameters, and plots represented that the particles were oscillating with a sinusoidal pattern in both cavities. The negative slope between 25 µm and 60 µm in far-infrared spectral distribution was encountered for both structures, which portrayed less number density of particles in 60 µm band; interaction between AGB wind and the ambient interstellar medium could be the possible reason behind this. These findings support the prior results for two new cavity structures nearby AGB stars within the galactic plane -10° < b < +10°.


2021 ◽  
Author(s):  
Seyed Majid Mosaddad

Abstract The Persian Gulf (PG) is a shallow sea connected to the rest of the world by the Strait of Hormuz. Temperature changes in the water column, which indicate the thermocline, are typically explained by the depth of the mixed layer and the thermocline. The thermocline is caused by a sudden decrease in temperature in the water column's subsurface layer, resulting in stratification in the PG from winter to summer. The parameters are approximated numerically through the Princeton Ocean Modeling (POM) method and compared to those determined by some CTD profiles collected in the PG. The most obvious method for approximating thermocline depth is to find the maximum negative slope \(\frac{\partial T}{\partial z}\) in a temperature profile. The method produces applied results with sufficient depth resolution and smooth temperature changes with depth. This method is a component of the Princeton Ocean Modeling (POM) framework for numerically modeling temperature variation in the water basins used in this study. The depth of the mixed layer is approximated by the surface equality temperature (Sea Surface Temperature), regardless of the thermocline approximation. The variable isotherm behavior accurately approximates the thermocline depth. Thermocline formation occurs in the PG during the summer, and this article will conclude using two methods, observational and numerical modeling.


Author(s):  
Romina San Miguel-Abella ◽  
Miguel Ángel Pérez-Sánchez ◽  
Fernando Cuetos ◽  
Javier Marín ◽  
María González-Nosti

AbstractSeveral studies have been carried out in various languages to explore the role of the main psycholinguistic variables in word naming, mainly in nouns. However, reading of verbs has not been explored to the same extent, despite the differences that have been found between the processing of nouns and verbs. To reduce this research gap, we present here SpaVerb-WN, a megastudy of word naming in Spanish, with response times (RT) for 4562 verbs. RT were obtained from at least 20 healthy adult participants in a reading-aloud task. Several research questions on the role of syllable frequency, word length, neighbourhood, frequency, age of acquisition (AoA), and the novel variable ‘motor content’ in verb naming were also examined. Linear mixed-effects model analyses indicated that (1) RT increase in with increasing word length and with decreasing neighbourhood size, (2) syllable frequency does not show a significant effect on RT, (3) AoA mediates the effect of motor content, with a positive slope of motor content at low AoA scores and a negative slope at high AoA scores, and (4) there is an interaction between word frequency and AoA, in which the AoA effect for low-frequency verbs gradually decreases as frequency increases. The results are discussed in relation to existing evidence and in the context of the consistency of the spelling–sound mappings in Spanish.


Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3616
Author(s):  
Kamilla M. S. Kaarsholm ◽  
Argyro Kokkoli ◽  
Eleni Keliri ◽  
Paul D. Mines ◽  
Maria G. Antoniou ◽  
...  

Chlorine is a widely used disinfectant and oxidant used for an array of municipal and industrial applications, including potable water, swimming pools, and cleaning of membranes. The most popular method to verify the concentration of free chlorine is the colorimetric method based on DPD (N, N-diethyl-p-phenylenediamine), which is fast and reasonably cheap, but DPD and its product are potentially toxic. Therefore, a novel, environmentally friendly colorimetric method for the quantification of residual chlorine based on the food additive pyridoxamine (4-(aminomethyl)-5-(hydroxymethyl)-2-methylpyridin-3-ol) was investigated. Pyridoxamine is a B6 vitamin with an absorption maximum at 324 nm and fluorescence emission at 396 nm. Pyridoxamine reacts rapidly and selectively with free chlorine, resulting in a linear decrease both in absorbance and in emission, giving therefore calibration curves with a negative slope. The pyridoxamine method was successfully applied for the quantification of free chlorine from 0.2 to 250 mg/L. Using 1 cm cuvettes, the limit of quantification was 0.12 mg Cl2/L. The pyridoxamine and the DPD methods were applied to actual environmental samples, and the deviation between results was between 4% and 9%. While pyridoxamine does not react with chloramine, quantification of monochloramine was possible when iodide was added, but the reaction is unfavourably slow.


2021 ◽  
Vol 931 ◽  
Author(s):  
Peter A. Monkewitz

The scaling of different features of streamwise normal stress profiles $\langle uu\rangle ^+(y^+)$ in turbulent wall-bounded flows is the subject of a long-running debate. Particular points of contention are the scaling of the ‘inner’ and ‘outer’ peaks of $\langle uu\rangle ^+$ at $y^+\approxeq ~15$ and $y^+ ={O}(10^3)$ , respectively, their infinite Reynolds number limit, and the rate of logarithmic decay in the outer part of the flow. Inspired by the thought-provoking paper of Chen & Sreenivasan (J. Fluid Mech., vol. 908, 2021, p. R3), two terms of an inner asymptotic expansion of $\langle uu\rangle ^+$ in the small parameter $Re_{\tau }^{-1/4}$ are constructed from a set of direct numerical simulations (DNS) of channel flow. This inner expansion is for the first time matched through an overlap layer to an outer expansion, which not only fits the same set of channel DNS within 1.5 % of the peak stress, but also provides a good match of laboratory data in pipes and the near-wall part of boundary layers, up to the highest $Re_{\tau }$ values of $10^5$ . The salient features of the new composite expansion are first, an inner $\langle uu\rangle ^+$ peak, which saturates at 11.3 and decreases as $Re_{\tau }^{-1/4}$ . This inner peak is followed by a short ‘wall log law’ with a slope that becomes positive for $Re_{\tau }$ beyond ${O}(10^4)$ , leading up to an outer peak, followed by the logarithmic overlap layer with a negative slope going continuously to zero for $Re_{\tau }\to \infty$ .


Land ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1190
Author(s):  
Peng Su ◽  
Shiqi Li ◽  
Jing’ai Wang ◽  
Fenggui Liu

Crop yields are threatened by global climate change. Maize has high water requirements, and precipitation fluctuations can impact its yield. In this study, we used the Environmental Policy Integrated Climate (EPIC) model to simulate maize yields in eight northeastern U.S. states. We used precipitation fluctuations and the coefficient of variation (CV) of yield as indicators to construct a vulnerability curve for the CV of yield and precipitation fluctuations. We then evaluated the vulnerability of maize yields under precipitation fluctuations in the region. We obtained the following results: (1) the fitted vulnerability curves were classified into three categories (positive slope, negative slope, and insignificant fit), of which the first category accounted for about 92.7%, indicating that the CV of maize yield was positively correlated with precipitation fluctuations in most parts of the study area; and (2) the CV of maize yield under 11 precipitation fluctuation scenarios was mapped to express the CV at the spatial level, and the maize yield in Connecticut and Maryland proved to be the most sensitive to precipitation fluctuations. This study provided a theoretical and experimental basis for the prevention of maize yield risk under fluctuating precipitation conditions.


Author(s):  
Mikhail Korpusenko ◽  
Farshid Manoocheri ◽  
Olli-Pekka Kilpi ◽  
Aapo Varpula ◽  
Markku Kainlauri ◽  
...  

Abstract We investigate the Predictable Quantum Efficient Detector (PQED) in the visible and near-infrared wavelength range. The PQED consists of two n-type induced junction photodiodes with Al2O3 entrance window. Measurements are performed at the wavelengths of 488 nm and 785 nm with incident power levels ranging from 100 µW to 1000 µW. A new way of presenting the normalized photocurrents on a logarithmic scale as a function of bias voltage reveals two distinct negative slope regions and allows direct comparison of charge carrier losses at different wavelengths. The comparison indicates mechanisms that can be understood on the basis of different penetration depths at different wavelengths (0.77 μm at 488 nm and 10.2 μm at 785 nm). The difference in the penetration depths leads also to larger difference in the charge-carrier losses at low bias voltages than at high voltages due to the voltage dependence of the depletion region.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259243
Author(s):  
Yuji Uchiyama ◽  
Hiroyuki Sakai ◽  
Takafumi Ando ◽  
Atsumichi Tachibana ◽  
Norihiro Sadato

Many older adults have difficulty seeing brief visual stimuli which younger adults can easily recognize. The primary visual cortex (V1) may induce this difficulty. However, in neuroimaging studies, the V1 response change to the increase of temporal frequency of visual stimulus in older adults was unclear. Here we investigated the association between the temporal frequency of flickering stimuli and the BOLD activity within V1 in older adults, using surface-based fMRI analysis. The fMRI data from 29 healthy older participants stimulated by contrast-reversing checkerboard at temporal flicker frequencies of 2, 4, and 8 Hz were obtained. The participants also performed a useful field of view (UFOV) test. The slope coefficient of BOLD activity regarding the temporal frequency of the visual stimulus averaged within V1 regions of interest was positive and significantly different from zero. Group analysis in the V1 showed significant clusters with positive slope and no significant clusters with a negative slope. The correlation coefficient between the slope coefficient and UFOV performance was not significant. The results indicated that V1 BOLD response to a flickering visual stimulus increases as the stimulus temporal frequency increases from 2 to 8 Hz in older adults.


2021 ◽  
Author(s):  
Young Eun Chon ◽  
Soo Young Park ◽  
Seung Up Kim ◽  
Han Pyo Hong ◽  
Jae Seung Lee ◽  
...  

Abstract Background Renal safety is a critical issue in chronic hepatitis B (CHB) patients receiving long-term entecavir (ETV) or tenofovir disofuroxil fumarate (TDF) therapy. We investigated their effects on estimated glomerular filtration rate (eGFR). Methods Treatment-naïve CHB patients receiving ETV or TDF for ≥1 year were recruited. The eGFR was assessed using the Chronic Kidney Disease Epidemiology Collaboration equation. We calculated average annual percent change (AAPC) in eGFR using Joinpoint regression. Results At beginning of observation, ETV group had unfavorable conditions than TDF group: lower eGFR and higher FIB-4 and APRI than TDF group (all P<0.001). After 6 years antiviral therapy, the mean eGFR in ETV group (n=1,793) was maintained (96.0 at first year to 95.6 mL/min/1.73 m2 at sixth year; AAPC -0.09%; P=0.322), whereas that in TDF group (n=1,240) significantly decreased annually (101.9 at first year to 96.9 mL/min/1.73 m2 at sixth year; AAPC -0.88%; P<0.001). Notably, in TDF group, even patients without diabetes (AAPC -0.80%; P=0.001) or hypertension (AAPC -0.87%; P=0.001) experienced significant decrease in eGFR. Expectably, accompanying diabetes (AAPC -1.59%; p=0.011) or hypertension (AAPC -1.00%; p=0.002) tended to accelerate eGFR decrease. TDF treatment (odds ratio 1.66, P<0.001), along with eGFR<60 mL/min/1.73 m2, serum albumin<3.5 mg/dL, and hypertension, were independently associated with ongoing renal dysfunction, defined as a negative slope of the mean eGFR change. Conclusions Compared to ETV, long-term TDF treatment induced slow, but progressive renal dysfunction. Although the annual eGFR change by TDF was small, careful monitoring is necessary, especially in patients requiring life-long therapy.


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