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121.
The PiDuce project comprises a programming language and a distributed runtime environment devised for experimenting Web services technologies by relying on solid theories about process calculi and formal languages for XML documents and schemas.The language features values and datatypes that extend XML documents and schemas with channels, an expressive type system with subtyping, a pattern matching mechanism for deconstructing XML values, and control constructs that are based on Milner’s asynchronous pi calculus. The runtime environment supports the execution of PiDuce processes over networks by relying on state-of-the-art technologies, such as XML schema and WSDL, thus enabling interoperability with existing Web services.We thoroughly describe the PiDuce project: the programming language and its semantics, the architecture of the distributed runtime and its implementation.  相似文献   
122.
Recent studies suggest a possible comorbidity between Attention-Deficit/Hyperactivity Disorder (ADHD) and obesity. To gain insight into this potential association, we performed a systematic review of the literature excluding case reports, non-empirical studies, and studies not using ADHD diagnostic criteria. Empirically based evidence suggests that obese patients referred to obesity clinics may present with higher than expected prevalence of ADHD. Moreover, all reviewed studies indicate that subjects with ADHD are heavier than expected. However, data on the prevalence of obesity in subjects with ADHD are still limited. As for the mechanisms underlying the potential association between ADHD and obesity, ADHD might lead to obesity via abnormal eating behaviors, impulsivity associated with binge eating might contribute to ADHD in obese patients, or, alternatively, both obesity and ADHD might be the expression of common underlying neurobiological dysfunctions, at least in a subset of subjects. In patients with obesity and ADHD, both conditions might benefit from common therapeutic strategies. Further empirically based studies are needed to understand the potential comorbidity between obesity and ADHD, as well as the possible mechanisms underlying this association. This might allow a more appropriate clinical management and, ultimately, a better quality of life for patients with both obesity and ADHD.  相似文献   
123.
The Mukaiyama–Michael‐type addition of various silyl ketene acetals or silyl enol ethers on some 1,2‐diaza‐1,3‐butadienes proceeds at room temperature in the presence of catalytic amounts of Lewis acid affording by heterocyclization 1‐aminopyrrol‐2‐ones and 1‐aminopyrroles, respectively. 1‐Aminoindoles have been also obtained by the same addition of 2‐(trimethylsilyloxy)‐1,3‐cyclohexadiene on some 1,2‐diaza‐1,3‐butadienes and subsequent aromatization. Mechanistic investigations indicate the coordination by Lewis acid of the enolsilyl derivative and its 1,4‐addition on the azo‐ene system of 1,2‐diaza‐1,3‐butadienes. The migration of the silyl group from a hydrazonic to an amidic nitrogen, its acidic cleavage and the final internal heterocyclization give the final products. Based on NMR studies and ab initio calculations, a plausible explanation for the migration of the silyl protecting group is presented.  相似文献   
124.
At the cutting-edge of microwave detection technology, novel approaches which exploit the interaction between microwaves and quantum devices are rising. In this study, microwaves are efficiently detected exploiting the unique transport features of InAs/InP nanowire double quantum dot-based devices, suitably configured to allow the precise and calibration-free measurement of the local field. Prototypical nanoscale detectors are operated both at zero and finite source-drain bias, addressing and rationalizing the microwave impact on the charge stability diagram. The detector performance is addressed by measuring its responsivity, quantum efficiency and noise equivalent power that, upon impedance matching optimization, are estimated to reach values up to ≈2000 A W−1, 0.04 and ≈ 10 16 W / H z ${10^{ - 16}}{\rm{W}}/\sqrt {Hz} $ , respectively. The interaction mechanism between the microwave field and the quantum confined energy levels of the double quantum dots is unveiled and it is shown that these semiconductor nanostructures allow the direct assessment of the local intensity of the microwave field without the need for any calibration tool. Thus, the reported nanoscale devices based on III-V nanowire heterostructures represent a novel class of calibration-free and highly sensitive probes of microwave radiation, with nanometer-scale spatial resolution, that may foster the development of novel high-performance microwave circuitries.  相似文献   
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