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11.
We describe a patient with aspergillosis of the maxillary antrum, and systemic affectation (anemia, anorexia, fever). Through a Caldwell-Luck approach, the maxillary antrum was opened and an irregular mass removed, postoperatively the patient has done well, disappearing in two months the ORL and systemic symptoms.  相似文献   
12.
The role of forest and bioenergy strategies in the global carbon cycle   总被引:1,自引:0,他引:1  
Forest and bioenergy strategies offer the prospect of reduced CO2 emissions to the atmosphere. Such strategies can affect the net flux of carbon to the atmosphere through 4 mechanisms: storage of C in the biosphere; storage of C in forest products; use of biofuels to displace fossil-fuel use; use of wood products which often displaces other products that require more fossil fuel for their production. We use the mathematical model GORCAM (Graz/Oak Ridge Carbon Accounting Model) to examine these mechanisms for 16 land-use scenarios. Over long time intervals the amount of C stored in the biosphere and in forest products reaches a steady state and continuing mitigation of C emissions depends on the extent to which fossil fuel use is displaced by the use of bioenergy and wood products. The relative effectiveness of alternative forest and bioenergy strategies and their impact on net C emissions strongly depend, for example, on the productivity of the site, its current usage, and the efficiency with which the harvest is used. When growth rates are high and harvest is used efficiently, the dominant opportunity for net reduction in C emissions is seen to be fossil-fuel displacement. At the growth rates and efficiencies of harvest utilization adopted in many of our base scenarios, the net C balance at the end of 100 years is very similar whether trees are harvested and used for energy and traditional forest products, or reforestation and forest protection strategies are implemented. The C balance on a plantation system that provides a constant output of biomass products can look different than the balance of a single parcel of land.  相似文献   
13.
Large-scale service-oriented computing is based on the idea that services from various servers are combined into one distributed application. Referring to a collection of services on one server as a ??service cloud??, the problem investigated in this paper is to define formal high-level specifications of such distributed applications and to enable the location of suitable services for them. Based on the language-independent model of Abstract State Services (AS2s), which serves as a universal integrated model for data and software as services, we extend AS2s by high-level action schemes called ??plots?? as a means to specify permitted sequences of service operations. On these grounds, we develop a model for service mediators, that is, specifications of composed services in which service slots have to be filled by actual services, and investigate matching conditions for slots of mediators and services. For a services to match a slot in a mediator, a (generalised) projection of the mediator must comply with the plot of the service. Furthermore, the service must be semantically adequate, which requires the use of a service ontology.  相似文献   
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The binary phase behavior of SOS (1,3-distearoyl-2-oleoyl-sn-glycerol) and SLS (1,3-distearoyl-2-linoleoyl-sn-glycerol) was examined by using DSC and conventional and synchrotron radiation X-ray diffraction. The solid-solution phases were observed in the metastable α and γ forms in all concentration ranges. Results indicated that the miscible γ form did not transform to the β′ form when the mixtures were subjected to simple cooling from a high-temperature liquid to a low-temperature solid phase. However, and α-melt-mediated transformation into β′ and β2 resulted in the formation of immiscible phases in concentration ranges of SLS below 30%. By contrast, at SLS concentration ranges above 30%, the α-melt-mediated transformation caused crystallization of only the γ form, and β′ and β2 crystals did not appear. These results show that the specific interactions between SOS and SLS are operative in the phase behavior of the mixture states of SOS and SLS.  相似文献   
16.
For a given $\theta \in (a,b)$ , we investigate the question whether there exists a positive quadrature formula with maximal degree of precision which has the prescribed abscissa $\theta $ plus possibly $a$ and/or $b$ , the endpoints of the interval of integration. This study relies on recent results on the location of roots of quasi-orthogonal polynomials. The above positive quadrature formulae are useful in studying problems in one-sided polynomial $L_1$ approximation.  相似文献   
17.
In this paper, a novel concept of a thermo-mechanical MEMS actuator using aluminum thin-film heaters on a thermal oxide for electrical insulation is presented. The actuator is part of an universal tensile testing platform for thermo-mechanical material characterization of one dimensional materials on a micro- and nano-scopic scale under different environmental conditions, as varying temperatures, pressure, moisture or even vacuum and is realised in BDRIE technology. It is shown, that the actuator concept fulfills the requirements for the use in a tensile loading stage along with heterogeneously integrated nanofunctional elements, following a specimen centered approach in line with bottom-up self-assembly processes. Simulation and experiment agree very well in the thermal and mechanical domain and allow subsequent optimisation of the actuator performance.  相似文献   
18.
Wafer-level Cu–Sn intermetallic bonding is an interesting process for advanced applications in the area of MEMS and 3D interconnects. The existence of two intermetallic phases for Cu–Sn system makes the wafer bonding process challenging. The impact of process parameters on final bonding layer quality have been investigated for transient liquid phase wafer-level bonding based on the Cu–Sn system. Subjects of this investigation were bonding temperature profile, bonding time and contact pressure as well as the choice of metal deposition method and the ratio of deposited metal layer thicknesses. Typical failure modes in intermetallic compound growth for the mentioned process and design parameters have been identified and were subjected to qualitative and quantitative analysis. The possibilities to avoid abovementioned failures are indicated based on experimental results.  相似文献   
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The potential of certain Auger electron emitting nuclides for systemic radiotherapeutic applications has recently gained much attention. In particular, the ability of several nuclides, including 111In, 125I, and 123I, to induce DNA double-strand breaks (dsb), a good indicator of cytotoxicity, has been extensively studied. However, this ability has never previously been shown experimentally for 99mTc, which, besides the well-known gamma radiation that is used for diagnostic applications, also emits an average of 1.1 conversion electrons and 4 Auger or Coster-Kronig electrons per decay. Owing to the short range of Auger electrons, the radionuclide needs to be located very close to the DNA for dsb to occur. We synthesized two cationic 99mTcI-tricarbonyl complexes with pendant DNA binders, pyrene and anthraquinone. The X-ray crystal structures of the two complexes could be elucidated. Linear dichroism and UV/Vis spectroscopy revealed that the complex with pyrene intercalates DNA with a stability constant, K, of 1.1 x 10(6) M(-1), while the analogous complex with anthraquinone interacts with DNA in a groove-binding mode and has an affinity value of K=8.9 x 10(4) M(-1). We showed with phiX174 double-stranded DNA that the corresponding 99mTc complexes induce a significant amount of dsb, whereas non-DNA-binding [TcO4]- and nonradioactive Re compounds did not. These results indicate that the Auger electron emitter 99mTc can induce dsb in DNA when decaying in its direct vicinity and this implies potential for systemic radiotherapy with 99mTc complexes.  相似文献   
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