Educação matemática pela arte
Gusmão, Lucimar Donizete
2013-08-28
Search results
22,909 records were found.
[Background]Peritoneal carcinomatosis is a poor prognostic factor for patients with gastrointestinal, gynecologic, and pancreatic cancer. Cisplatin (CDDP) is among the most effective anti-cancer agents, although its adverse effects remain unresolved. For the treatment of peritoneal carcinomatosis with high-dose CDDP, it is necessary to design a new delivery system of CDDP that can decrease systemic toxicity and achieve a better targeted, high-dose chemotherapy. [Methods]Microspheres were prepared from gelatin of a nontoxic, biodegradable material for the sustained release of CDDP. The gelatin microspheres incorporating CDDP (GM-CDDP) were injected intraperitoneally into a mouse model of peritoneal carcinomatosis; their therapeutic efficacy and adverse effects were evaluated in comparison with intraperitoneal administration of free CDDP...
Coda-Q is a stochastic parameter reflecting the heterogeneities of medium that seismic waves travel through. We confirmed that coda-Q would vary with the stress loaded to an elastic medium using numerical simulations of seismic wave propagation. When the stress is loaded, cracks in the crust could either close or newly open. The closure and opening of the cracks are not random but depending on the magnitude and the direction of the stress and the crack aspect ratio. The cracks in the medium after loading stress could be aligned in a specific orientation, and elastic wave velocity field would become anisotropic due to the alignment of specific crack orientations. Elastic wave velocity is in general faster along the direction corresponding with the crack orientation while slower along the perpendicular direction. In the numerical simulat...
Kurihara established a refinement of the minus-part of the Iwasawa main conjecture for totally real number fields by using the higher Fitting ideals [Ku]. In this paper, by using Kuriharaʼs methods and Mazur–Rubin theory, we study the higher Fitting ideals of the plus-part of Iwasawa modules associated with the cyclotomic Zp-extension of abelian fields for an odd prime number p. We define the higher cyclotomic ideals, which are ideals of the Iwasawa algebra defined by the Kolyvagin derivative classes of circular units. Then, we prove that the higher cyclotomic ideals give upper and lower bounds of the higher Fitting ideals in some sense, and determine the pseudo-isomorphism classes of the plus-part of Iwasawa modules. Our results can be regarded as analogues of Kuriharaʼs results and a refinement of the plus-part of the Iwasawa main co...
Field investigations reveal spatial variations in fault zone width along strike-slip active faults of the Arima–Takatsuki Tectonic Line (ATTL) and the Rokko–Awaji Fault Zone (RAFZ) of southwest Japan, which together form a left-stepping geometric pattern. The fault zones are composed of damage zones dominated by fractured host rocks, non-foliated and foliated cataclasites, and a fault core zone that consists of cataclastic rocks including fault gouge and fault breccia. The fault damage zones of the ATTL are characterized by subsidiary faults and fractures that are asymmetrically developed on each side of the main fault. The width of the damage zone varies along faults developed within granitic rocks of the ATTL and RAFZ, from ∼50 to ∼1000 m. In contrast, the width of the damage zone within rhyolitic tuff on the northwestern side of the...
High-velocity friction (HVF) experiments on serpentinite under conditions equivalent to large amounts of earthquake slip produced large volumes of water vapor derived from the frictional-heating-induced dehydration of serpentinite. Fourier Transform Infrared (FTIR) and thermogravimetry (TG)-Differential Scanning Calorimetry (DSC) microspectroscopic analyses show that the water in the slip zone and its bounding zones was released due to dehydration during the HVF experiments. Our experimental results demonstrate that (i) the run product consists of ~ 10 wt.% molten materials with abundant vesicles and ~ 90 wt.% fine-grained clasts; (ii) both serpentine and olivine minerals were melted during high-velocity slip (1.1–1.3 m/s); (iii) rapid serpentine dehydration occurred in a zone of up to ~ 3 mm wide, including the slip zone and its bound...
In cognitive radio networks, secondary spectrum users detect available frequency channels by spectrum sensing. In general, the sensing time is communication overhead, and affects system's performance. In this paper, we theoretically consider the effect of sensing overhead on the system performance for cognitive radio networks with channel bonding. Specifically, we model the system with a multidimensional continuous-time Markov chain whose state is defined by the numbers of primary users, secondary users, and sensing users. The blocking probability, the forced termination probability and the throughput are derived. The analysis is validated by Monte Carlo simulation. Numerical examples show that the forced termination probability is not affected by sensing overhead, while the blocking probability and the throughput degrade with the incr...
