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Herein, porous carbon materials rich in oxygen (O)-containing functional groups and with abundant micropores were synthesized by carbonizing lychee seeds activated with various activators at a relatively low temperature of 600 °C. The incorporation of potassium and sodium salts during activation effectively modulated both the surface O functionalities and the microporous structure of the resulting porous carbon materials. The influence of these characteristics on CO2 adsorption performance was systematically investigated. A multiple linear regression model was developed to evaluate the impact of key factors including cumulative pore volumes in the pore size range of 5-7 Å (V5-7 Å), 0-10 Å (V0-10 Å), and 0-20 Å (V0-20 Å), total pore volume (VT), and the contents of C=OOH and C-OH groups on the CO2 adsorption capacity of the carbon materials at 1 bar and 25 °C. Results revealed that the C=OOH content is the most significant factor affecting CO2 uptake, while C-OH content and V0-20 Å also play important secondary roles. Notably, the LS-KOH-600 sample exhibited a high CO2 adsorption capacity, reaching 5 mmol/g at 25 °C and 7.15 mmol/g at 0 °C (1 bar). Furthermore, LS-KOH-600 demonstrated excellent CO2/N2 selectivity (29.9) and good cyclic stability under simulated flue gas conditions.
Phytophthora capsici is rapidly becoming an important limiting factor in vegetable production in the southeastern United States, particularly on cucurbits as fruit rots. One of the strategies used to manage diseases caused by P. capsici is the regular application of fungicides. Recently the new fungicide cyazofamid (trade name Ranman, FRAC Group 21, FMC Corporation, EPA Reg. No. 71512-3-279) was registered for management of P. capsici on cucurbits. Cyazofamid has been reported to be very effective against P. capsici on peppers (1). In a recent evaluation, we observed that cyazofamid was not very effective on fruit rot of watermelon in a field artificially infested with P. capsici (3). Hence, we evaluated our collection of isolates for sensitivity to cyazofamid. We confirmed our isolates as P. capsici based on morphology of colonies and sporangia and amplification of internal transcribed spacer regions using specific PCR primers (4). Mycelial growth of 28 isolates from the southeastern United States including North (NC) and South Carolina (SC), Georgia (GA), and Florida (FL) was evaluated on Ranman amended (0, 25, 100, 310, 518, and 1,000 mg/liter of the active ingredient cyazofamid) V8 juice agar using similar techniques as described before (2). The EC50 (50% effective concentration) values ranged from 3.8 to 535 mg/liter. Thirteen isolates (8 GA, 3 SC, 1 NC, and 1 FL) had EC50 >100 mg/liter. Similar results were obtained when technical grade cyazofamid was used. The same 28 isolates were evaluated on media amended with technical grade cyazofamid (0, 1, 10, and 100 mg/liter) and 100 mg/liter of salicylhydroxaymic acid, which was added to inhibit the alternative oxidase enzyme. The EC50 values ranged from <1 to >100 mg/liter. Six isolates (5 GA and 1 NC) had EC50 >100 mg/liter. Three isolates, one sensitive and two insensitive, were used to inoculate cucumber (Cucumis sativus) fruits treated with commercial Ranman at 0, 10, 100, 300, and 1,000 mg/liter of cyazofamid plus the surfactant Silwett L-77 (0.52 ml/liter). Mycelial plugs (7-mm diameter) were placed on nonwounded fruits. Fruits were kept under high humidity at 25 ± 1°C in an incubator for 3 days. Two measurements of each lesion at right angles were averaged to get the lesion diameter. The EC50 value for lesion diameter on fruits varied from 13 mg/liter for the sensitive isolate to >233 mg/liter for the insensitive isolates. EC50 values for diameter of the lesion with sporulation ranged from 3 to 107 mg/liter. Relative lesion diameters of the insensitive isolates at 100 mg/liter treatment compared with nonsprayed check were 70 to 93%, and at 300 mg/liter, it was 38 to 80%. Similarly in another experiment, watermelon (Citrullus lanatus var. lanatus) fruits were sprayed with a recommended field rate of Ranman (284 mg of cyazofamid/liter) plus Silwett L-77 (0.52 ml/liter) till runoff and inoculated with four isolates. The relative lesion diameter for insensitive isolates on Ranman treated watermelon fruits were 76 to 100% of nonsprayed fruits. To our knowledge, these insensitive isolates were collected from fields that were never sprayed with Ranman. Because of the existence of cyazofamid insensitive P. capsici isolates, it should be rotated with fungicides from other chemical classes to prevent extensive selection of insensitive isolates. References: (1) K. L. Ivors et al. Plant Dis. Manage. Rep. 1:V088, 2007. (2) A. P. Keinath. Plant Dis. 91:743, 2007. (3) C. S. Kousik and R. Hassell. Plant Dis. Manage. Rep. 1:V010, 2007. (4) J. B. Ristaino et al. Appl. Environ. Microbiol. 64:948, 1998.
Ivabradine is a selective bradycardic agent that reduces the heart rate (HR) by inhibiting the hyperpolarization-activated cyclic nucleotide-gated channels. Although its cardiovascular effect is thought to be minimal except for inducing bradycardia, ivabradine could interact with cardiovascular regulation by the autonomic nervous system. We tested whether ivabradine modifies dynamic characteristics of peripheral vagal HR control. In anesthetized Wistar-Kyoto rats (n = 7), the right vagal nerve was sectioned and stimulated for 10 min according to a binary white noise sequence with a switching interval of 500 ms. The efferent vagal nerve stimulation (VNS) trials were performed using three different rates (10, 20, and 40 Hz), and were designated as V0-10, V0-20, and V0-40, respectively. The transfer function from the VNS to the HR was estimated before and after the intravenous administration of ivabradine (2 mg/kg). Ivabradine increased the asymptotic dynamic gain in V0-20 [from 3.88 (1.78-5.79) to 6.62 (3.12-8.31) beats·min-1·Hz-1, P < 0.01, median (range)] but not in V0-10 or V0-40. Ivabradine increased the corner frequency in V0-10 [from 0.032 (0.026-0.041) to 0.064 (0.029-0.090) Hz, P < 0.01] and V0-20 [from 0.040 (0.037-0.056) to 0.068 (0.051-0.100) Hz, P < 0.01] but not in V0-40. In conclusion, ivabradine augmented the dynamic HR response to moderate VNS. At high VNS, however, ivabradine did not significantly augment the dynamic HR response, possibly because ivabradine reduced the baseline HR and limited the range for the bradycardic response to high VNS.NEW & NOTEWORTHY Ivabradine is considered to be a pure bradycardic agent that has little effect on cardiovascular function except inducing bradycardia. The present study demonstrated that ivabradine interacts with the dynamic vagal heart rate control in a manner that augments the heart rate response to moderate-intensity efferent vagal nerve stimulation.
Studies suggest that postoperative complications are a risk factor for venous thromboembolism (VTE) after bariatric surgery. Knowledge of factors associated with a higher risk of VTE after bariatric surgery may be essential to select patients who may benefit from either prolonged or intensified thrombosis prophylaxis. The aim of this study is to determine the relationship between postoperative complications and VTE after bariatric surgery and other classical risk factors. A retrospective multicenter case-control study was performed in patients who had bariatric surgery between January 2008 and September 2011. VTE until 6 months after surgery was registered, and patients were contacted to ascertain the results. For every case of VTE after surgery, 6 control patients were selected who were matched for gender, age, participating center and type of surgery. Risk factors for VTE before and after surgery and postoperative complications were registered. A total of 2,064 surgeries were included. In 12 patients, VTE occurred within 6 months after bariatric surgery (incidence 0.58 %, 95 % confidence interval (CI) = 0.25-0.93). There was a strong association of complications after surgery (cases 91.7 %, controls 15.3 %, odds ratio (OR) 61.0; 95 % CI = 7.1-521.3) or intensive care admission (cases 50.0 %, controls 11.1 %, OR = 8.0; 95 % CI = 2.1-30.8) with VTE. The majority of postoperative complications were anastomotic leak, abdominal abscess, and infection. We could not detect an association between classical thrombosis risk factors and postoperative VTE. The incidence of VTE is low after bariatric surgery using thrombosis prophylaxis. However, there is a strong association between postoperative complications and VTE. These patients may benefit from more intensive thrombosis prophylaxis.
Our previous study indicated that intravenously administered ivabradine (IVA) augmented the dynamic heart rate (HR) response to moderate-intensity vagal nerve stimulation (VNS). Considering an accentuated antagonism, the results were somewhat paradoxical; i.e., the accentuated antagonism indicates that an activation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels via the accumulation of intracellular cyclic adenosine monophosphate (cAMP) augments the HR response to VNS, whereas the inhibition of HCN channels by IVA also augmented the HR response to VNS. To remove the possible influence from the accentuated antagonism, we examined the effects of IVA on the dynamic vagal control of HR under β-blockade. In anesthetized rats (n = 7), the right vagal nerve was stimulated for 10 min according to binary white noise signals between 0 and 10 Hz (V0-10), between 0 and 20 Hz (V0-20), and between 0 and 40 Hz (V0-40). The transfer function from VNS to HR was estimated. Under β-blockade (propranolol, 2 mg/kg iv), IVA (2 mg/kg iv) did not augment the asymptotic low-frequency gain but increased the asymptotic high-frequency gain in V0-10 (0.53 ± 0.10 vs. 1.74 ± 0.40 beats/min/Hz, P < 0.01) and V0-20 (0.79 ± 0.14 vs. 2.06 ± 0.47 beats/min/Hz, P < 0.001). These changes, which were observed under a minimal influence from sympathetic background tone, may reflect an increased contribution of the acetylcholine-sensitive potassium channel (IK,ACh) pathway after IVA, because the HR control via the IK,ACh pathway is faster and acts in the frequency range higher than the cAMP-mediated pathway.NEW & NOTEWORTHY Since ivabradine (IVA) inhibits hyperpolarization-activated cyclic nucleotide-gated channels, interactions among the sympathetic effect, vagal effect, and IVA can occur in the control of heart rate (HR). To remove the sympathetic effect, we estimated the transfer function from vagal nerve stimulation to HR under β-blockade in anesthetized rats. IVA augmented the high-frequency dynamic gain during low- and moderate-intensity vagal nerve stimulation. Untethering the hyperpolarizing effect of acetylcholine-sensitive potassium channels after IVA may be a possible underlying mechanism.
The purpose of this study was to determine the relationship between strength - power parameters and sprint performance and to predict sprint times from strength - power parameters. Twenty-five male young sprinters participated in this study. Squat Jump(SJ), counter-movement jump (CMJ), drop jump height (DJH), repeated jump(RJ) and 100m sprint time from block start, including reaction time (RT) and times at 10m, 30m and 60m were measured. Reactive strength index (RSI), the difference between counter-movement and squat jump (CMJ-SJ) and the mean velocities of the intermediate sections 0-10m, 10-30m, 30-60m, 60-100 m (V0-10, V10-30, V30-60 and V60-100) were also calculated. The canonical correlation analysis with strength - power parameters as predictors and reaction time and mean velocities as dependent variables revealed two canonical variables that explained 89.6% of the total variance. The first canonical variable (R=0.840) explained the association between SJ, RJ, DJH, RSI and all mean velocities. The second canonical variable (R=0.707) had only one predictor, CMJ-SJ, and loaded only on RT. Stepwise multiple regression analysis confirmed that RT depends only on CMJ-SJ. V0-10 depends on both DJ and SJ, while V10-30 depends only on SJ. Finally, V30-60 and V60-100 are primarily dependent on RSI. Multiple regression analysis of the 100m sprint time revealed that 46.5% of the variability could be explained by the variability of the strength- power predictors. Performance at 100m sprint is strongly associated with strength-power parameters. The best predictor of the overall performance is probably SJ (or CMJ).
Cassini data has revealed a surprising twist in Saturn’s magnetic shield: the planet’s rapid rotation appears to drag a key opening in its magnetosphere far toward the afternoon side instead of keeping it near noon, as happens on Earth。 The finding confirms that giant planets like Saturn operate under a fundamentally different magnetic regime, wher
James Webb has captured a striking new infrared view of NGC 2392, the Lion Nebula, revealing the dramatic aftermath of a dying Sun-like star。 At its center, a scorching white dwarf is blasting radiation into surrounding gas and dust, carving out the nebula’s lion-like face while illuminating a sprawling “mane” of surviving dusty clumps
Photons traveling through a cloud of atoms can emerge so early that they appear to have spent a negative amount of time inside。 Researchers tested whether this was merely a misleading feature of the light pulse by making extremely weak measurements of the atoms。 Surprisingly, the atoms confirmed the same negative dwell time
NASA’s Curiosity rover has entered a Martian valley covered by an astonishing “sea” of tiny polygon-shaped fractures。 The honeycomb patterns, each only a few inches wide, stretch across the landscape and even wrap around a nearby 20-foot-tall butte
Scientists have built the first all-optical photonic time crystal, allowing them to reshape the behavior of terahertz light at extraordinary speeds。 The breakthrough could open the door to ultrafast computing, smarter communication systems, advanced imaging, and a new generation of highly tunable lasers
NASA is assembling the foundations of a future Moon Base through a wave of robotic missions and powerful new commercial landers。 More than 20 landings are planned through 2029, testing everything from precision landings and lunar communications to rovers, power systems, and technology that can survive the Moon’s extreme conditions。 Upcoming mission
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people。 Frequent contact was linked to greater tension and mistrust, while the crew increasingly divided into cultural and language-based groups
“It’s the strongest evidence yet that particles dominated by a glueball component can exist in nature
Hundreds of Homeland Security drones retasked to survey wildlife and livestock
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AI firms quietly bulk buying rare books face resistance from booksellers