The presence of water greatly influences time-dependent rock deformation. An understanding of how water can affect the time-dependent mechanical behavior of rock is important when assessing the ...long-term stability of geotechnical projects. While the previous studies have performed brittle creep experiments on oven-dry or fully-saturated rocks, we report here on a study designed to better understand brittle creep at different levels of saturation. We performed brittle creep experiments on oven-dry samples of red sandstone (Hunan province, China) and samples of the sandstone pre-immersed in water for different durations (from 2 to 8 days). These samples were deformed at a constant stress in one of either two conditions: dry or submerged in water. Before performing creep experiments, we first performed a series of water absorption and constant stress rate experiments to guide the stresses required for our creep tests and to assist with their interpretation. Our creep experiments show that immersion in water greatly increased the minimum creep strain rate and greatly shortened the time-to-failure when compared to the dry state. In detail, the minimum creep strain rate and time-to-failure increased and decreased, respectively, as pre-immersion duration increased from 4 to 6 days, but did not change as the duration was further increased to 8 days. We attribute this to the saturation of microcracks between 4 and 6 days (i.e., water imbibition was complete, or close to completion, following 6 days). We also show that oven-dry samples deformed at a constant stress underwater fail at stresses much lower than oven-dry samples deformed under dry conditions, due to the imbibition of water during deformation. Samples pre-immersed in water, but deformed in the dry condition were characterized by lower strain rates and longer time-to-failure than those pre-immersed in water and deformed underwater. Our explanation for this is that, due to the availability of water, crack tips can remain hydrated when the sample is deformed underwater, thus increasing the efficacy of stress corrosion cracking. The relationships and data provided herein inform on the long-term stability of engineering structures.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Capacitive deionization (CDI) has been considered as a low energy consumption, economically attractive and environmental friendly method for desalination of salt water. Generally, the electrode ...materials play the key role in CDI. In the present work, representative activated carbons (ACs) recycled from bitter-tea and palm shell wastes (denoting BAC and PAC, respectively) were used as the CDI electrodes. To provide additional disinfection ability during CDI of salt water, Ag@C core-shell nanoparticles prepared from carbonization of Ag+-cyclodextrin complexes at 673 K were dispersed on the AC electrodes. By FTIR, it seems that the ACs have the less oxygen on their surfaces with more aromatic contents if the compared with the shell wastes as the carbon sources. Electrosorption efficiencies during the one-through CDI of a salt water (NaCl = 1000 ppm) using the BAC and PAC electrodes at +1.2 V are 25 and 28%, respectively. As the voltage is increased to +1.6 V, the electrosorption efficiencies and recovery performances of the PAC and Ag@C/PAC electrodes during the repeated CDI tests (+1.6 V → 0 V → +1.6 V) are similar to those operated at 1.2 V. However, after the potential polarity is reversed (+1.6 V to −1.6 V), their electrosorption efficiencies are considerably increased (capable of 40%). The ACs dispersed with the Ag@C nanoparticles (Ag@C/AC) has less contact angles, giving a better hydrophilicity. High disinfection abilities (95–98%) for the Ag@C/ACs electrodes during the 2-h CDI reaction can be obtained. This work exemplifies that the ACs recycled from shell wastes as CDI electrodes for desalination of salt water are chemically feasible. In addition, the AC-based CDI electrodes dispersed with Ag@C core-shell nanoparticles have additional disinfection ability during desalination of salt water.
•The activated carbon (AC) recycled from shell wastes for capacitive deionization (CDI) of salt water is chemically feasible.•The electrosorption efficiency of the recycled AC electrode can be increased up to 40%.•The AC electrode dispersed with Ag@C core-shell nanoparticles has extra disinfection ability during CDI of salt water.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Novel zinc anodes are synthesized via electroplating with organic additives in the plating solution. The selected organic additives are cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate ...(SDS), polyethylene-glycol (PEG-8000), and thiourea (TU). The synthesized zinc anode materials, namely, Zn-CTAB, Zn-SDS, Zn-PEG, and Zn-TU, are characterized by powder X-ray diffraction and scanning electron microscopy. The results show that each additive produces distinctively different crystallographic orientation and surface texture. The surface electrochemical activity is characterized by linear polarization when the zinc is in contact with the battery’s electrolyte. Tafel fitting on the linear polarization data reveals that the synthetic zinc materials using organic additives all exhibit 6–30 times lower corrosion currents. When using Zn-SDS as the anode in the rechargeable hybrid aqueous battery, the float current decreases as much as 2.5 times. The batteries with Zn-SDS, Zn-PEG, and Zn-TU anodes display the capacity retention of 79%, 76%, and 80% after 1000 cycles of charge–discharge at 4C rate, whereas only 67% obtained from the batteries using the anode prepared from commercial zinc foil. Among these electroplated anodes, Zn-SDS is the most suitable for aqueous batteries thanks to its low corrosion rate, low dendrite formation, low float current, and high capacity retention after 1000 cycles.
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IJS, KILJ, NUK, PNG, UL, UM
Retinal ganglion cells (RGCs) are the sole output neurons that transmit visual information from the retina to the brain. Diverse insults and pathological states cause degeneration of RGC somas and ...axons leading to irreversible vision loss. A fundamental question is whether manipulation of a key regulator of RGC survival can protect RGCs from diverse insults and pathological states, and ultimately preserve vision. Here, we report that CaMKII-CREB signaling is compromised after excitotoxic injury to RGC somas or optic nerve injury to RGC axons, and reactivation of this pathway robustly protects RGCs from both injuries. CaMKII activity also promotes RGC survival in the normal retina. Further, reactivation of CaMKII protects RGCs in two glaucoma models where RGCs degenerate from elevated intraocular pressure or genetic deficiency. Last, CaMKII reactivation protects long-distance RGC axon projections in vivo and preserves visual function, from the retina to the visual cortex, and visually guided behavior.
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•Excitotoxic and axonal injuries lead to loss of CaMKII activity in RGCs•Reactivation of CaMKII protects RGCs in multiple injury/disease models•CREB acts downstream of CaMKII in protecting RGCs•Reactivation of CaMKII protects visual pathway and preserves functional vision
CaMKII-CREB signaling plays a major role in maintenance of retinal ganglion cells (RGCs), and reactivation of CaMKII activity via AAV gene therapy in injury and disease models in mice protects RGCs and preserves visual function and visually guided behavior.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ABSTRACT It has been revealed that the magnetic topology in the solar atmosphere displays hemispheric preference, i.e., helicity is mainly negative/positive in the northern/southern hemispheres, ...respectively. However, the strength of the hemispheric rule and its cyclic variation are controversial. In this paper, we apply a new method based on the filament drainage to 571 erupting filaments from 2010 May to 2015 December in order to determine the filament chirality and its hemispheric preference. It is found that 91.6% of our sample of erupting filaments follows the hemispheric rule of helicity sign. It is also found that the strength of the hemispheric preference of the quiescent filaments decreases slightly from ∼97% in the rising phase to ∼85% in the declining phase of solar cycle 24, whereas the strength of the intermediate filaments keeps a high value around 96 4% at all times. Only the active-region filaments show significant variations. Their strength of the hemispheric rule rises from ∼63% to ∼95% in the rising phase, and keeps a high value of 82% 5% during the declining phase. Furthermore, during a half-year period around the solar maximum, their hemispheric preference totally vanishes. Additionally, we also diagnose the magnetic configurations of the filaments based on our indirect method and find that in our sample of erupting events, 89% are inverse-polarity filaments with a flux rope magnetic configuration, whereas 11% are normal-polarity filaments with a sheared arcade configuration.
A sensitivity analysis of a mathematical model of a lithium-sulfur (Li–S) battery was performed, focusing on the effects of the discharge current and the electronic conductivity of the cathode by ...investigating the response of the model to variations of these parameters over a wide range of values. The behavior of the model battery system with respect to the variations of each parameter is explained in detail. The nonlinear response of the model to the parameter variations is presented. In particular, the discharge current causes different patterns of the voltage plateaus. The importance of the electronic conductivity of the cathode is also discussed in detail. A minimum conductivity requirement to activate the cell was observed, beyond which no significant improvement of the capacity performance occurs. This report evaluates the electrochemical aspects of different experimental results particularly regarding discharge voltage plateaus, and moreover, demonstrates the limits of the model.
•The discharge behavior of Li–S cells in a wide range of current rate is studied.•Sulfur must highly dissolve in electrolyte to maintain high capacity performance.•A threshold of cathode's conductivity exists bellow which the cell would not operate.•Above the conductivity threshold no capacity loss is observed due to conductivity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence ...tomography (OCT) angiography technique.
Cross-sectional, observational study.
Twenty-eight normal, 30 POAG, and 31 NTG subjects.
One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program.
Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH.
Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes.
Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for diagnosis and monitoring of glaucoma.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
HLA-A*31:01 was reported to be associated with carbamazepine (CBZ)-induced severe cutaneous adverse reactions (SCAR), including drug reaction with eosinophilia and systemic symptoms (DRESS), ...Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). We conducted an international study using consensus diagnosis criteria to enroll a total of 93 patients with CBZ-SCAR from Europe or Asia. We found that HLA-A*31:01 showed a significant association with CBZ-DRESS in Europeans (P<0.001; odds ratio (OR) (95% confidence interval (CI))=57.6 (11.0-340)), and the strong association was also found in Chinese (P<0.001; OR (95% CI)=23.0 (4.2-125)). However, HLA-A*31:01 had no association with CBZ-SJS/TEN in neither Chinese nor Europeans. By comparison, HLA-B*15:02 showed a strong association with CBZ-SJS/TEN in Chinese (P<0.001, OR (95% CI)=58.1 (17.6-192)). A meta-analysis of this and other published studies confirmed that in all populations, HLA-A*31:01 had an extremely strong association with CBZ-DRESS (P<0.001, a pooled OR (95% CI)=13.2 (8.4-20.8)), but a much weaker association with CBZ-SJS/TEN (P=0.01, OR (95% CI)=3.94 (1.4-11.5)). Our data revealed that HLA-A*31:01 is a specific predictor for CBZ-DRESS but not for CBZ-SJS/TEN. More studies are needed to investigate the genetic determinant of CBZ-SJS/TEN in Europeans. Considering the potential clinical utility, the cost-effectiveness of the combined HLA-A*31:01 and HLA-B*15:02 genetic test to prevent CBZ-SCAR in Chinese needs further investigation.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Summary
Long‐term prognosis varies widely among patients with hepatitis B virus (HBV)‐related liver cirrhosis. Our study aimed to investigate the applicability of albumin‐bilirubin (ALBI), Child‐Pugh ...and model for end‐stage liver disease (MELD) scores to the long‐term prognosis prediction of HBV‐related cirrhosis. Patients diagnosed with HBV‐associated cirrhosis from the First Affiliated Hospital of Wenzhou Medical University between January 2010 and December 2015 were enrolled in this study. The patients were followed up every 3 months. The prognostic performance of ALBI in long‐term outcome prediction for HBV‐related cirrhosis was compared with Child‐Pugh and MELD scores using time‐dependent receiver operating characteristic curve (tdROC) and decision curve analysis. A total of 806 patients were included in our study with 275 (34.1%) deceased during the follow‐up. Multivariate Cox regression analysis showed that ALBI grade was an independent predictor associated with mortality. The tdROC analysis showed that ALBI score (0.787, 0.830 and 0.833) was superior to MELD (0.693, P=.003; 0.717, P<.001; 0.744, P<.001) and Child‐Pugh score (0.641, P<.001; 0.649, P<.001; 0.657, P<.001) for predicting 1‐year, 2‐year and 3‐year mortality. Additionally, decision curves also got the similar results. In addition, patients with lower ALBI score had a longer life expectancy, even among patients within the same Child‐Pugh class. Thus, ALBI score was effective in predicting the long‐term prognosis for patients with HBV‐related cirrhosis and more accurate than Child‐Pugh and MELD scores.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Antler and limb bone have a similar microstructure and chemical composition. Both are primarily composed of type I collagen and a mineral phase (carbonated apatite), arranged in osteons in compact ...(cortical bone) sections and a lamellar structure in the cancellous (spongy or trabecular bone) sections. The mineral content is lower in antler bone and it has a core of cancellous bone surrounded by compact bone running through the main beam and tines. The mineral content is higher in the compact compared with the cancellous bone, although there is no difference in ratios of the mineral elements with calcium. Mechanical tests (bend and compression) on longitudinal and transverse orientations of dry and rehydrated compact bone of North American elk (Cervus elaphus canadensis) antlers are compared with known data on other antlers as well as bovine femora. Both dry and rehydrated bones are highly anisotropic, with the bending and compressive strength and elastic modulus higher in the longitudinal than in the transverse direction. There is no significant difference between the bend strength and elastic modulus between dry and rehydrated samples tested in the transverse direction. The elastic modulus measured from the bending tests is compared with composite models. The elastic modulus and bend strengths are lower in the rehydrated condition, but the strain to failure and fracture toughness is much higher compared with dry samples. All antler bone mechanical properties are lower than that of bovine femora. The antler has a much higher fracture toughness compared with bovine femora, which correlates with their main function in intraspecific combat as a high impact resistant, energy absorbent material. A model of compression deformation is proposed, which is based on osteon sliding during shear.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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