854 research outputs found
An Alternative Fuel Refueling Station Location Model considering Detour Traffic Flows on a Highway Road System
With the development of alternative fuel (AF) vehicle technologies, studies on finding the potential location of AF refueling stations in transportation networks have received considerable attention. Due to the strong limited driving range, AF vehicles for long-distance intercity trips may require multiple refueling stops at different locations on the way to their destination, which makes the AF refueling station location problem more challenging. In this paper, we consider that AF vehicles requiring multiple refueling stops at different locations during their long-distance intercity trips are capable of making detours from their preplanned paths and selecting return paths that may be different from original paths for their round trips whenever AF refueling stations are not available along the preplanned paths. These options mostly need to be considered when an AF refueling infrastructure is not fully developed on a highway system. To this end, we first propose an algorithm to generate alternative paths that may provide the multiple AF refueling stops between all origin/destination (OD) vertices. Then, a new mixed-integer programming model is proposed to locate AF refueling stations within a preselected set of candidate sites on a directed transportation network by maximizing the coverage of traffic flows along multiple paths. We first test our mathematical model with the proposed algorithm on a classical 25-vertex network with 25 candidate sites through various scenarios that consider a different number of paths for each OD pair, deviation factors, and limited driving ranges of vehicles. Then, we apply our proposed model to locate liquefied natural gas refueling stations in the state of Pennsylvania considering the construction budget. Our results show that the number of alternative paths and deviation distance available significantly affect the coverage of traffic flows at the stations as well as computational time
Antioxidant capacities and polyphenolics of Chinese cabbage (Brassica rapa L. ssp. Pekinensis) leaves
a b s t r a c t Chinese cabbage (Brassica rapa L. ssp. Pekinensis) is a green leafy vegetable used mainly in kimchi, salted and fermented dishes. Consumer preference for the leaf portion differs according to the type of dishes. In this study, Chinese cabbage was divided into three parts, and their antioxidant activities were investigated through in vitro assays. The total phenolic contents (TPC), total flavonoid contents (TFC), and vitamin C contents were also determined as indicators of antioxidant contents. The phenolic acids and flavonoids were separated and identified using high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). The outer leaf had the strongest antioxidant activity with the maximum antioxidant contents, followed by the mid-and inner leaves. Principal component analysis (PCA) revealed that outer leaf is positively related to caffeic acid, p-coumaric acid, ferulic acid, and myricetin contents, whereas the mid-and inner leaves are negatively related to sinapic acid contents
Correlation between thigh skinfold thickness and physical fitness factors in Korean adults and older individuals
Background: This cross-sectional epidemiological study aimed to compare
the differences in physical fitness variables according to the skinfold thickness
in the thigh area in adults and Korean older individuals. Methods: We analyzed data from the 2015 National Fitness Survey. A
total of 4034 healthy adults (2442 men, 1592 women) with an average age of 38.19
± 12.41 years and 880 healthy older subjects (369 men, 511 women) with an
average age of 72.32 ± 5.49 years participated in this study. The skinfold
thickness of the thigh was measured using a skinfold caliper (Dynatron,
Dynatronics, USA). The participants underwent physical fitness tests, including
the hand squeeze strength test, abdominal curl ups, standing double-leg long
jump, 50 m shuttle run, sit and reach, and 20 m shuttle run for adult men and
women. Older men and women performed the following tests: hand squeeze strength,
abdominal curl ups, sit to stand test, single leg balance (open eyes), sit and
reach, Apley scratch test for shoulder mobility, and 6-minute walk test.
Independent t-tests and Pearson correlation analyses were used for the
analysis. Results: Among the older men, significant differences were found in
thigh skinfold thickness (t = â21.122, p < 0.001), abdominal
curl ups (t = 2.165, p = 0.031), and sit and reach in men
(t = 2.609, p = 0.009), and thigh skinfold (t =
â29.611, p < 0.001), and Apley scratch test for shoulder mobility in
women (t = â2.120, p = 0.034). There was a significant
correlation between thigh skinfold thickness and physical activity (thigh
skinfold thickness) in adult men (t = â54.202, p < 0.001),
nondominant hand squeeze strength (t = 2.632, p = 0.009),
abdominal curl ups (t = 4.292, p < 0.001), sit and reach
(t = 3.063, p = 0.002), twenty meters shuttle run (t =
4.657, p < 0.001).
However, no significant differences were found in
dominant hand squeeze strength, standing double leg long jump, or 50 m shuttle
run in men (p < 0.05). In adult women, there was a significant
correlation between thigh skinfold thickness and physical activity (thigh
skinfold thickness (t = â49.405, p < 0.001), dominant hand
squeeze strength (t = 7.789, p < 0.001), nondominant hand
squeeze strength (t = 6.944, p < 0.001), abdominal curl ups
(t = 5.347, p < 0.001), standing double leg long jump
(t = 5.890, p < 0.001), sit and reach (t = 5.384,
p < 0.001), twenty meter shuttle run (t = 5.223, p < 0.001).
However, no significant differences were found in fifty meter shuttle
run in women (p < 0.05). Among older men, only single leg balance and
sit and reach were correlated with thigh skinfold (single leg balance r
= 0.169, p = 0.01; sit and reach r = â0.201, p =
0.001). In women, only abdominal curl ups, sit and reach, and Apley scratch test
correlated with thigh skinfold (abdominal curl ups r = â0.088,
p = 0.002; sit and reach r = â0.137, p = 0.002; Apley
scratch test r = 0.090, p = 0.041). Conclusions: The effect of thigh skinfold thickness on the level of
physical activity was more pronounced in adults than in older subjects. Our
findings show that muscle strength and body fat in the lower extremities can
affect overall muscle strength, endurance, and balance
The Globular Cluster System of M60 (NGC 4649). I. CFHT MOS Spectroscopy and Database
We present the measurement of radial velocities for globular clusters in M60,
giant elliptical galaxy in the Virgo cluster. Target globular cluster
candidates were selected using the Washington photometry based on the deep
16\arcmin \times 16\arcmin images taken at the KPNO 4m and using the
photometry derived from the HST/WFPC2 archive images. The spectra of the target
objects were obtained using the Multi-Object Spectrograph (MOS) at the
Canada-France-Hawaii Telescope (CFHT). We have measured the radial velocity for
111 objects in the field of M60: 93 globular clusters (72 blue globular
clusters with and 21 red globular clusters with
), 11 foreground stars, 6 small galaxies, and the nucleus of
M60. The measured velocities of the 93 globular clusters range from
km s to km s, with a mean value of
km s, which is in good agreement with the velocity of the nucleus of M60
( km s). Combining our results with data in the
literature, we present a master catalog of radial velocities for 121 globular
clusters in M60. The velocity dispersion of the globular clusters in the master
catalog is found to be km s for the entire sample,
km s for 83 blue globular clusters, and
km s for 38 red globular clusters.Comment: 29 pages, 8 figures. To appear in Ap
Comparison of standard versus 90° rotation technique for LMA Flexible⹠insertion: a randomized controlled trial
Background
Insertion of a flexible laryngeal mask airway (LMA Flexible) is known to be more difficult than that of a conventional laryngeal mask airway. The 90° rotation technique can improve the success rate with a conventional laryngeal mask airway but its effect with the LMA Flexible remains unknown. We assessed whether the 90° rotation technique increased the first-attempt success rate of LMA Flexible insertion versus the standard technique.
Methods
In total, 129 female patients undergoing breast surgery were analyzed. The primary endpoint was success at the first attempt. The insertion time, number of trials, number of manipulations required, and oropharyngeal leak pressure were also evaluated. Heart rate and mean blood pressure were recorded 1âmin before and 1âmin after insertion. Blood staining on the LMA Flexible after removal and postoperative sore throat were checked.
Results
The first-attempt success rates were comparable between the groups (93% vs. 98.3%, Pâ=â.20). The insertion time, number of trials and manipulations, hemodynamic variables, and complications, such as blood staining and sore throat, did not differ between the groups.
Conclusions
The 90° rotation technique is a good alternative to the standard technique for insertion of the LMA Flexible.
Trial registration
ClinicalTrials.gov(NCT03028896). It was registered retrospectively at Jan 19th, 2017.ASA: American Society of Anesthesiologists; BMI: Body mass index; IV: Intravenous; LMA: Laryngeal mask airway; MAP: Mean arterial pressure; NRS: Numerical rating scale; PACU: Post-anesthetic care unit; SD: Standard deviatio
Effects of Textural Properties on the Response of a SnO2-Based Gas Sensor for the Detection of Chemical Warfare Agents
The sensing behavior of SnO2-based thick film gas sensors in a flow system in the presence of a very low concentration (ppb level) of chemical agent simulants such as acetonitrile, dipropylene glycol methyl ether (DPGME), dimethyl methylphosphonate (DMMP), and dichloromethane (DCM) was investigated. Commercial SnO2 [SnO2(C)] and nano-SnO2 prepared by the precipitation method [SnO2(P)] were used to prepare the SnO2 sensor in this study. In the case of DCM and acetonitrile, the SnO2(P) sensor showed higher sensor response as compared with the SnO2(C) sensors. In the case of DMMP and DPGME, however, the SnO2(C) sensor showed higher responses than those of the SnO2(P) sensors. In particular, the response of the SnO2(P) sensor increased as the calcination temperature increased from 400 °C to 800 °C. These results can be explained by the fact that the response of the SnO2-based gas sensor depends on the textural properties of tin oxide and the molecular size of the chemical agent simulant in the detection of the simulant gases (0.1â0.5 ppm)
Rescue Endovascular Treatment to Prevent Neurological Deterioration in Acute Symptomatic Bilateral Vertebral Artery Occlusion
Bilateral vertebral artery occlusive disease has been considered as a favorable condition with good collaterals. However, the prognosis of acute ischemic stroke secondary to symptomatic bilateral vertebral artery occlusion (BVAO) and endovascular treatment (EVT) has rarely been reported. We retrospectively selected patients with acute ischemic stroke admitted for symptomatic BVAO between January 2020 and February 2023. All patients with ischemic stroke were evaluated for ischemic lesion and arterial status using brain imaging and angiography. The prognosis of acute stroke with symptomatic BVAO was compared between EVT and conventional treatment. Outcomes were evaluated using modified Rankin Scale (mRS) score at 3 months follow-up. Within the study period, 17 of 2,655 acute ischemic stroke patients were diagnosed with ischemic stroke with symptomatic BVAO. The median age of these patients was 70 (interquartile range 44â89) years, and 13 (76%) were male. Seven patients received emergent EVT with stenting and 10 patients received conventional medical treatment only. Nine of 10 patients with conventional treatment had in-hospital stroke progression and developed new ischemic lesions in the pons and midbrain. Five patients with fetal and hypoplastic posterior communicating artery presented bilateral cerebral peduncular lesions. At 3 months follow-up, 6 patients (35%) had favorable outcomes (mRS 0â2), of which 5 were treated with vertebral artery stenting and 1 received conventional treatment. Ischemic stroke in patients with acute symptomatic BVAO is uncommon. However, stroke progression is common, and the prognosis of most patients is poor. Rescue management such as EVT might be considered for symptomatic BVAO
The Globular Cluster System of M60 (NGC 4649). II. Kinematics of the Globular Cluster System
We present a kinematic analysis of the globular cluster (GC) system in the
giant elliptical galaxy (gE) M60 in the Virgo cluster. Using the photometric
and spectroscopic database of 121 GCs (83 blue GCs and 38 red GCs), we have
investigated the kinematics of the GC system. We have found that the M60 GC
system shows a significant overall rotation. The rotation amplitude of the blue
GCs is slightly smaller than or similar to that of the red GCs, and their
angles of rotation axes are similar. The velocity dispersions about the mean
velocity and about the best fit rotation curve for the red GCs are marginally
larger than those for the blue GCs. Comparison of observed stellar and GC
velocity dispersion profiles with those calculated from the stellar mass
profile shows that the mass-to-light ratio should be increased as the
galactocentric distance increases, indicating the existence of an extended dark
matter halo. The entire sample of GCs in M60 is found to have a tangentially
biased velocity ellipsoid unlike the GC systems in other gEs. Two subsamples
appear to have different velocity ellipsoids. The blue GC system has a modest
tangentially biased velocity ellipsoid, while the red GC system has a modest
radially biased or an isotropic velocity ellipsoid. From the comparison of the
kinematic properties of the M60 GC system to those of other gEs (M87, M49, NGC
1399, NGC 5128, and NGC 4636), it is found that the velocity dispersion of the
blue GC system is similar to or larger than that of the red GC system except
for M60, and the rotation of the GC system is not negligible. The entire sample
of each GC system shows an isotropic velocity ellipsoid except for M60, while
the subsamples show diverse velocity ellipsoids. We discuss the implication of
these results for the formation models of the GC system in gEs.Comment: 48 pages, 16 figures. To appear in Ap
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