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The nonlinear features of dust-acoustic waves in a strongly coupled unmagnetized dusty plasma containing electrons and ions following q-nonextensive distribution, and negatively charged mobile dust are investigated by using the reductive perturbation method. The effects of important parameters, such as the q-parameter, temperature, density, and velocity on the properties of solitary and shock waves are discussed. The conditions for the formation of solitary structures and monotonic and oscillatory shock structures are also found. The implications of our result in space and laboratory dusty plasmas are discussed. PACS Nos: 52.27.Gr, 52.27.Lw, 52.35.Mw, 52.35.Fp, 52.35.Sb La methode des perturbations reductives nous permet d'etudier les caracteristiques non lineaires d'ondes acoustiques de poussiere dans un plasma poussiereux non magnetise et fortement couple contenant des electrons et des ions suivant une distribution non extensive a parametre q et des particules de poussiere portant une charge negative. Nous analysons les effets des parametres importants, que sont le parametre q, la temperature, la densite et la vitesse, sur les proprietes des ondes de choc solitaires. [Traduit par la Redaction], 1. Introduction Nonlinear dust-acoustic waves have received a great deal of attention to understand the properties of localized electrostatic perturbations in space and laboratory dusty plasmas [1, 2]. Nonlinear dust-acoustic [...]

The roles of intracellular calcium concentration ([[[Ca.sup.2+].sub.i]) and [Ca.sup.2+] sensitization in lipopolysaccharide (LPS)-induced vascular smooth muscle (VSM) hyporesponsiveness are incompletely understood. To investigate these roles, contraction responses to endothelin-1 (ET-1) and 80 mM KC1; relaxation responses to nifedipine; the expression levels of mRNAs of ET-1 and its receptors ([ET.sub.A] or [ET.sub.B]); the expression levels of protein kinase C (PKC) and phosphorylation of Rho kinase (ROK[alpha], CPI-17, and myosin phosphatase target subunit-1 (MYPT1); and changes in aortic VSM cell [[[Ca.sup.2+].sub.i] were measured in LPS-treated aortic rings from male Wistar rats (250-300 g). LPS (10 [micro]g/ml, 20 h) decreased contraction induced by ET-1 (0.3-100 nM) or 80 mM KC1. LPS-induced hypocontractility was not observed in the absence of external [Ca.sup.2+], but LPS-treated aorta remained hypocontractile on subsequent stepwise restoration of extracellular [Ca.sup.2+] (0.01-10 mM). Vascular relaxation to nifedipine; mRNA expression levels of ET-I, [ET.sub.A], or [ET.sub.B]; protein expression levels of PKC; and phosphorylation levels of ROK[alpha], CPI-17, and MYPT1 were not affected by LPS. In isolated aortic VSM cells, ET-1 caused a transient initial increase in [[[Ca.sup.2+].sub.i], followed by a maintained tonic increase in [[[Ca.sup.2+].sub.i], which was decreased by LPS pretreatment and was dependent on external [Ca.sup.2+]. Subsequent restoration of extracellular [Ca.sup.2+] increased [[[Ca.sup.2+].sub.i], but this increase was lower in the LPS-treated group. This difference in response to extracellular [Ca.sup.2+] addition was not affected by diltiazem, but was abolished by SKF-96365. Therefore, LPS induces hyporeactivity to ET-1 in rat aorta that depends on external [Ca.sup.2+] influx through non-voltage-operated [Ca.sup.2+] channels, but not on ET-1 receptor expression or [Ca.sup.2+] sensitization. calcium sensitization; sepsis; vascular smooth muscle

The usual approach to bring the value of the process capability index, [C.sub.pk], to an acceptable level is to design equipment and develop a process in which the process variable is robust to external disturbances. However, an alternative approach involves the use of in situ sensors and real-time feedback control. Currently this approach is not widely implemented in the semiconductor industry. In this paper we provide analytic justification to quantify the potential improvement in [C.sub.pk] if a real-time feedback control scheme is used instead of the usual open-loop approach. We show that for the case of feedback control the level of [C.sub.pk], is only limited by the accuracy and reproducibility of the sensor provided that the target values are indeed achievable by the processing equipment. This result also holds in the presence of disturbances and nonlinearities. [C.sub.pk]. values for open-loop and real-time feedback control strategies are compared for two experimental applications: single-wafer CVD nitride and polysilicon processes.

A thermal cycling system for baking and chilling semiconductor wafers is presented for photoresist processing applications. The proposed unit differs from conventional systems as the bake and chill steps are conducted sequentially within the same module without substrate movement. The unit includes a circulating fluid that can be switched between hot and cold reservoirs and serves as the dominant means for heat transfer. A set of thermoelectric devices is used in conjunction with the hot/cold fluid to provide a distributed amount of heat to the wafer for uniformity and transient temperature control. Experimental results are provided to demonstrate temperature uniformity during both transient and steady-state operation. Index Terms - Lithography, photoresist, temperature control.