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This paper proposes several blind adaptive receivers to eliminate multiple-access interference (MAI), intersymbol interference (ISI), and interchip interference (ICI) in direct-sequence code-division multiple access (DS/CDMA) downlink multiuser systems. We use the following concepts to formulate the cost function: 1) the variance of the despreading output approaches to the variance of the desired signal and 2) the discreteness property of the input signal. The proposed approaches are called variance-oriented approaches (VOAs). The VOA is then applied to three proposed receiver structures, especially the generalized sidelobe canceller (GSC) scheme that is generally the concept of spatial domain in beamforming system, to eliminate the MAI by one particular constraint in temporal domain. Besides, by this constraint, GSC filter possesses the property of global convergence in multipath environment once the channel estimation is appropriate. Simulation examples are shown to demonstrate the effectiveness and comparison of the proposed blind adaptive receivers. Index Terms--Downlink direct-sequence code-division multiple access (DS/CDMA), generalized sidelobe canceller (GSC), multiple-access interference (MAI).

Two monolithic 3-bit active phase shifters using the vector sum method to K-band frequencies are reported in this paper. They are separately implemented using commercial 6-in GaAs HBT and high electron-mobility transistor (HEMT) monolithic-microwave integrated-circuit (MMIC) foundry processes. The MMIC HBT active phase shifter demonstrates an average gain of 8.87 dB and a maximum phase error of 11[degrees] at 18 GHz, while the HEMT phase shifter has 3.85-dB average measured gain with 11[degrees] maximum phase error at 20 GHz. The 20-GHz operation frequency of this HEMT MMIC is the highest among all the reported active phase shifters. The analysis for gain deviation and phase error of the active phase shifter using the vector sum method due to the individual variable gain amplifiers is also presented. The theoretical analysis can predict the measured minimum root-mean-square phase error 4.7[degrees] within 1[degrees] accuracy. Index Terms--Active phase shifter, HBT, high electron-mobility transistor (HEMT), K-band, monolithic microwave integrated circuit (MMIC), vector sum method.

Background: Sepsis constitutes a condition that involves life-threatening organ dysfunction induced by severe infection. This nested case–control study investigated risk factors for severe sepsis and whether antipsychotic use is associated with severe sepsis risk in patients with schizophrenia, a topic that has not been comprehensively explored in previous studies. Methods: We selected 39,432 patients with schizophrenia aged between 15 and 65 years from Taiwan's Psychiatric Inpatient Medical Claims database for the period 2000–2012. The case group comprised patients with severe sepsis after their first psychiatric admission (n = 1382). The case and control groups were randomly matched (1:4) by age, sex and first psychiatric admission (year) and finally comprised 1382 and 5528 individuals, respectively. We employed multivariable conditional logistic regression to identify (1) risk factors (physical illnesses and nonpsychiatric medications) and (2) antipsychotic–severe sepsis associations. Results: Higher numbers of psychiatric admissions and physical illnesses such as delirium, cerebrovascular disease and cancer were significantly associated with a higher risk of severe sepsis. Furthermore, severe sepsis was associated with the use of antithrombotic agents, systemic corticosteroids and agents targeting the renin–angiotensin system. Clozapine (adjusted risk ratio = 1.65) and quetiapine (adjusted risk ratio = 1.59) use were associated with an increased risk of severe sepsis. The use of more than one antipsychotic drug could further increase this risk. Conclusion: Several physical illnesses and nonpsychiatric medications increase the risk of severe sepsis in patients with schizophrenia. Specifically, clozapine or quetiapine use significantly increased the risk of severe sepsis in these patients. [ABSTRACT FROM AUTHOR]

Fine Co(OH)2 powder was prepared by simple precipitation from aqueous solutions of cobalt sulfate and sodium hydroxide without using sophisticated reagents and/or approaches. The fine powder was homogeneously mixed with protonated betaine bis((trifluoromethyl)sulfonyl)amide ionic liquid ([Hbet][TFSA] IL), an amide-type hydrophobic protic IL, and then dispersed in ethanol with graphene nanopowder for being spin-coated upon screen-printed carbon electrode (SPCE) to prepare the glucose-reactive electrode. Activation of the electrode was essential to expose the glucose-oxidation activity, and the experimental evidences indicated that Co3O4 converted from Co(OH)2 during the activation process was the active species in charge of glucose oxidation. The electrode showed a wide linear dynamic range for glucose from 1 to 1757 µM with a high sensitivity of 632 µA cm− 2 mM− 1 and a detection limit of 1 µM in the electrolyte containing 0.5 M NaOH and 0.1 M NaCl. The electrode showed no response to common interferants, including alcohols, in the concentration the same as to glucose. However, ascorbic acid in the same concentration level showed severe interference but negligible in the physiological level. This study shows that Co(OH)2 prepared by facile precipitation is qualified of being an efficient electrocatalyst precursor for glucose oxidation, and IL is a good binder for immobilizing the electrocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • The TSIC model facilitates the design of complex interface composites with stiff and compliant materials. • Control of the tensile and shear interface thickness allows tuning of the composites' stiffness and strength, respectively. • Fracture analysis reveals non-columnar fractures as a key to enhancing interface hardening in TSICs. • UV curing during printing results in a gradient elastic modulus at stiff-soft interfaces, enhancing strength compared to non-UV-cured samples. The rapid growth of polyjet additive manufacturing has propelled the 3D printing of multi-material polymer composites toward unprecedented applications. Interfaces in such composites play a paramount role in determining mechanical performance. This study delves into the crucial role of interfaces, employing VeroWhite and Agilus30Black materials to scrutinize the tensile and shear properties of stiff-soft interfaces. By applying these layers strategically, composites with multi-oriented interfaces were created, revealing the impact of soft material thickness and orientation on stiffness and strength. We identified columnar and non-columnar fracture mechanisms, shedding light on their correlation with interface hardening. Nanoindentation tests unveil the local interface properties, emphasizing the gradient change in elastic modulus when printed on the x -axis and the sharp drop on the z -axis. These findings offer valuable insights into material selection and interface optimization, providing a roadmap for achieving tailored mechanical properties in complex interface composites. [ABSTRACT FROM AUTHOR]