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Paul Grocki Mark Woollam Luqi Wang Shengzhi Liu Maitri Kalra Amanda P. Siegel Bai-Yan Li Hiroki Yokota Mangilal Agarwal 《Molecules (Basel, Switzerland)》2022,27(13)
Volatile organic compounds (VOCs) in urine are potential biomarkers of breast cancer. Previously, our group has investigated breast cancer through analysis of VOCs in mouse urine and identified a panel of VOCs with the ability to monitor tumor progression. However, an unanswered question is whether VOCs can be exploited similarly to monitor the efficacy of antitumor treatments over time. Herein, subsets of tumor-bearing mice were treated with pitavastatin at high (8 mg/kg) and low (4 mg/kg) concentrations, and urine was analyzed through solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Previous investigations using X-ray and micro-CT analysis indicated pitavastatin administered at 8 mg/kg had a protective effect against mammary tumors, whereas 4 mg/kg treatments did not inhibit tumor-induced damage. VOCs from mice treated with pitavastatin were compared to the previously analyzed healthy controls and tumor-bearing mice using chemometric analyses, which revealed that mice treated with pitavastatin at high concentrations were significantly different than tumor-bearing untreated mice in the direction of healthy controls. Mice treated with low concentrations demonstrated significant differences relative to healthy controls and were reflective of tumor-bearing untreated mice. These results show that urinary VOCs can accurately and noninvasively predict the efficacy of pitavastatin treatments over time. 相似文献
13.
The ac conductivity in evaporated amorphous germanium films has been measured as a function of annealing and has been found to obey the ω0.8 law, in accordance with the hopping model. The dc conductivity measurements on the same samples show a law behaviour. The densities of localized states near the Fermi level g(EF), obtained from both experiments are in reasonable agreement with each other. Both the measurements show a reduction by about a factor of 2 in g(EF) when a freshly prepared film is fully annealed. High-temperature substrate films also show the ω0.8 behaviour. This suggests that the frequency dependence of the ac conductivity is not caused by voids alone. Other possible explanations of our results are also discussed. 相似文献
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Ravinder Agarwal V. R. Singh M. M. Pradhan Ved Singh 《International Journal of Infrared and Millimeter Waves》1991,12(2):115-123
The occurance of the urinary stones varies according to the geographical regions. The presence of stones in the urinary system causes pain and discomfort. These generate colics and hence are sometimes life threatening. In the present study, infrared measurements have been made on several stone samples. It has been found that calcium oxalate, calcium phosphate, magnesiunm ammonium phosphate, calcium carbonate, uric acid, -cystine and xanthin are present, as expected. Also, silicon dioxide is found to be present in some of the stones but in small quantity, in addition to the above constituents. This constituent is responsible to exhibit piezoelectricity in the urinary calculi. 相似文献
16.
Ravi P. Agarwal Said R. Grace Donal O'Regan 《Proceedings of the American Mathematical Society》2003,131(1):129-140
This paper introduces a nonoscillatory theory for differential inclusions based on fixed point theory for multivalued maps.
17.
Localized state conduction through a variable-range hopping mechanism in the low-temperature region (~180–270 K) and thermally activated phonon-assisted tunneling in the higher-temperature region (~270–320 K) has been observed in a polycrystalline Sb35Se65 sample. 相似文献
18.
Miguel Vivas-Cortez Muhammad Aamir Ali Hüseyin Budak Humaira Kalsoom Praveen Agarwal 《Entropy (Basel, Switzerland)》2021,23(7)
In this investigation, for convex functions, some new –Hermite–Hadamard-type inequalities using the notions of derivative and integral are obtained. Furthermore, for -differentiable convex functions, some new () estimates for midpoint and trapezoidal-type inequalities using the notions of integral are offered. It is also shown that the newly proved results for and can be converted into some existing results. Finally, we discuss how the special means can be used to address newly discovered inequalities. 相似文献
19.
Ravi P. Agarwal Fatemah Mofarreh Rasool Shah Waewta Luangboon Kamsing Nonlaopon 《Entropy (Basel, Switzerland)》2021,23(8)
This research article is dedicated to solving fractional-order parabolic equations using an innovative analytical technique. The Adomian decomposition method is well supported by natural transform to establish closed form solutions for targeted problems. The procedure is simple, attractive and is preferred over other methods because it provides a closed form solution for the given problems. The solution graphs are plotted for both integer and fractional-order, which shows that the obtained results are in good contact with the exact solution of the problems. It is also observed that the solution of fractional-order problems are convergent to the solution of integer-order problem. In conclusion, the current technique is an accurate and straightforward approximate method that can be applied to solve other fractional-order partial differential equations. 相似文献
20.
Nanowires offer a unique approach for the bottom-up assembly of electronic and photonic devices with the potential of integrating photonics with existing technologies. The anisotropic geometry and mesoscopic length scales of nanowires also make them very interesting systems to study a variety of size-dependent phenomenon where finite-size effects become important. We will discuss the intriguing size-dependent properties of nanowire systems with diameters in the 5–300?nm range, where finite-size and interfacial phenomena become more important than quantum mechanical effects. The ability to synthesize and manipulate nanostructures by chemical methods allows tremendous versatility in creating new systems with well-controlled geometries, dimensions, and functionality, which can then be used for understanding novel processes in finite-sized systems and devices. 相似文献