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A backpack energy harvester (EH) managed by a modified fly-back converter is proposed. This modified fly-back converter is controlled by a constant-on time control (COT) algorithm, The COT is one of pulse frequency modulation schemes, which switches in boundary conduction mode. Due to the structure of the modified fly-back converter and the alternator, the energy delivery to battery is proportional to the voltage of coupled capacitor. As opposed to the conventional fly-back, the proposed modified fly-back has the metal–oxide–semiconductor field-effect transistor and the capacitor exchanged in roles to achieve input rectified voltage sensing. Moreover, the proposed modified fly-back converter utilizes the internal winding inductance of the alternator utilized as part of the fly-back converter, to save the size of the converter circuitry and lower the cost. With the COT control strategy, the output power is estimated by measuring the capacitor voltage, which is converted to digitals by a 10-bit analog-to-digital converter and a time-to-digital converter. The results show clearly the fair linearity between the rotational speed of alternator, capacitor voltage and output power. Finally, the control algorithm of boundary conduction mode (BCM) is utilized for tackling well the intermittent input power generated by the EH. The average output powers of 1.166 W for striding and 1.766 W for jogging are successfully achieved. [ABSTRACT FROM AUTHOR]

A new wireless power-transfer circuitry with a single-stage regulating rectifier is designed by this study for wearable flexible sensor patches. The patch is orchestrated to measure personal physiological status ubiquitously for long-time care. To ensure high wearability of the patch, the patch usually cannot equipped with a bulky battery for long-time sensing. Instead, wireless power transfer (WPT) is applied to charge a small-sized battery in the patch for ubiquitous and long-term sensing. In this paper, a single-stage regulating rectifier is presented to implement the receiver part of the WPT used in flexible sensor patches, significantly reducing the conduction loss and the complexity of the receiver circuitry, which is usually in a 2-stage topology. It is operating in the Industrial Scientific and Medical (ISM) band, 13.56 MHz. It is integrated with delay lock loop (DLL) feedback to improve high efficiency to solve the problem of long turn-off time. The single-stage regulating rectifier is implemented with 1×/0× mode and pulse frequency modulation control algorithm to regulate the output voltage. The proposed WPT circuit is fabricated by the TSMC 0.35 μm process in a total area of the proposed chip is 2.72 mm2. The output voltage can be regulated in 3.3 V to provide power to the sensor patch. The peak efficiency is achieved as 86% with the output power of 200 mW and the setup time is 11 μs from light load to regular load transient response, a favorable integrated performance as compared to prior arts. [ABSTRACT FROM AUTHOR]

In this study, Ga-doped ZnO (GZO) transparent conducting thin films were prepared by pulsed direct-current magnetron sputtering, providing good transparency and relatively low resistivity. The films were further etched in different aqueous solutions, 0.5% HCl, 5% oxalic acid, and 33% KOH, to modify their light-scattering properties. The results showed that film textured by 0.5% HCl for 30 s had total optical transparency of T = 77.4% and haze value of H = 0.16, with electrical resistivity of ρ = 4.9 × 10 Ω-cm. For film textured in 5% oxalic acid solution for 75 s, the lowest electrical resistivity of 4.3 × 10 Ω-cm was achieved with relatively high total optical transparency of T = 75.1%, as well as a more ideal haze value of H = 0.3. Film textured in 33% KOH solution for 135 s (500 nm thickness) had optimal electrical conductivity of 5.1 × 10 Ω-cm with T = 75.6%, and a relatively low haze value of H = 0.12. GZO film textured with an agitated etch of 5% oxalic acid at 300 K would be the most suitable candidate for photovoltaic applications due to its high transparency and good electrical conducting properties. [ABSTRACT FROM AUTHOR]

We investigate the undetermined sets consisting of two-level, multi-partite pure quantum states, whose reduced density matrices give absolutely no information of their original states. Two approached of finding these quantum states are proposed. One is to establish the relation between codewords of the stabilizer quantum error correction codes (SQECCs) and the undetermined states. The other is to study the local complementation rules of the graph states. As an application, the undetermined states can be exploited in the quantum secret sharing scheme. The security is guaranteed by their undetermineness. [ABSTRACT FROM AUTHOR]

A strong earthquake occurred in Wenchuan County, Sichuan Province, China, on May 12, 2008. Shortly after the earthquake, the Turner-Fairbank Highway Research Center of the Federal Highway Administration, in partnership with the Research Institute of Highways, the Ministry of Communication of China, led a reconnaissance team to conduct a post-earthquake bridge performance investigation of the transportation system in the earthquake affected areas. The U.S. transportation system reconnaissance team visited the area during July 20-24, 2008. This paper presents the findings and lessons learned by the team. [ABSTRACT FROM AUTHOR]

The present study determined the influence of a retinoid X receptor agonist bexarotene on angiogenesis and metastasis in solid tumours. In the experimental lung metastasis xenograft models, treatment with bexarotene inhibited the development of the lung tumour nodule formation compared to control. In vivo angiogenesis assay utilising gelfoam sponges, bexarotene reduced angiogenesis in sponges containing vascular endothelial growth factor, epidermal growth factor and basic fibroblast growth factor to various extent. To determine the basis of these observations, human breast and non-small-cell lung cancer cells were subjected to migration and invasion assays in the presence of bexarotene. Our data showed that bexarotene decrease migration and invasiveness of tumour cells in a dose-dependent manner. Furthermore, bexarotene inhibited angiogenesis by directly inhibiting human umbilical vein endothelial cell growth and indirectly inhibiting tumour cell-mediated migration of human umbilical vein endothelial cells through Matrigel matrix. Analysis of tumour-conditioned medium indicated that bexarotene decreased the secretion of angiogenic factors and matrix metalloproteinases and increased the tissue inhibitor of matrix metalloproteinases. The ability of bexarotene to inhibit angiogenesis and metastasis was dependent on activation of its heterodimerisation partner peroxisome proliferator-activated receptor gamma. Collectively, our results suggest a role of bexarotene in treatment of angiogenesis and metastasis in solid tumours. [ABSTRACT FROM AUTHOR]

Presents the results of a study in which quality of life data were used to evaluate the effects of self-administered intracavernosal injection of alprostadil for erectile dysfunction, when used for up to 18 months during a Phase III clinical trial. Improvement in patients' mental and social health and self-esteem at six months; Improvement in anxiety and depression measures at 12 and 18 months.

A search has been made for new particles with charge Q=2/3, 1, 4/3, 5/3 produced in e e-reactions at PETRA. The energy range was E=27-35 GeV. No such particles were found. Upper limits for the cross-section depending on the assumed mass and production spectrum are given. For Q=2/3 quarks with mass less than 12 GeV/ c, upper limits $${{\sigma \left( {q\bar q} \right)} \mathord{\left/ {\vphantom {{\sigma \left( {q\bar q} \right)} {\sigma \left( {\mu \mu } \right)}}} \right. \kern-\nulldelimiterspace} {\sigma \left( {\mu \mu } \right)}} \leqq 10^{ - 2} $$ (90% C.L.) are obtained both for inclusive and exclusive production. For the lifetime of the B-meson ( m=5GeV/ c) an upper limit τ≦2×10s is obtained. [ABSTRACT FROM AUTHOR]

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Study Design: Literature Review., Objective: Review the etiology, clinical manifestations, diagnosis, and treatment of pelvic obliquity in cerebral palsy patients with neuromuscular scoliosis. Neuromuscular scoliosis (NMS) in cerebral palsy (CP) patients is rapidly progressive and often leads to an imbalance in musculoskeletal mechanics that extends to the pelvis. A horizontal misalignment of the pelvis in the frontal plane known as pelvic obliquity (PO) is a common finding in this population. When untreated, PO can exacerbate the back pain, postural strain, and walking difficulties experienced by these patients. Establishing the manifestation and treatment plan for PO in the setting of NMS can provide valuable insight for diagnosis and management., Methods: A comprehensive literature review was performed on the etiology, clinical manifestations, diagnosis, and treatment of pelvic obliquity in the setting of NMS in CP. The advantages and limitations of measurement and treatment options were evaluated., Results: PO is categorized into suprapelvic, infrapelvic, and intrapelvic causes, each presenting with a unique pattern of pathology. NMS in CP with hip contractures and structural deformities fall into these categories. The Maloney and O'Brien methods of pelvic measurement have demonstrated superior utility and are recommended for clinical diagnosis. The management of PO in NMS patients is focused on the cause of malalignment, with posterior fusion, contracture release, and osteotomy encompassing the mainstay of treatment., Conclusion: PO is commonly found in patients with NMS in cerebral palsy. There is currently no standard method for determining the PO angle. Interventions designed to reduce scoliotic curves and release tissue contractures can level the pelvis and restore proper alignment of the spine and sacrum in the coronal plane in these patients. Further understanding of the causes of PO in NMS, as well as the establishment of a standardized measuring technique and diagnostic parameters will allow for more effective treatment options and improve outcomes in patients with CP., Level of Evidence: N/A., (© 2021. Scoliosis Research Society.)