Superconducting quantum interference devices(SQUIDs) are low-noise amplifiers that are essential for the readouts of translation edge sensors(TESs). The linear flux range is an important parameter for SQUID amplifiers...Superconducting quantum interference devices(SQUIDs) are low-noise amplifiers that are essential for the readouts of translation edge sensors(TESs). The linear flux range is an important parameter for SQUID amplifiers, especially those controlled by high-bandwidth digital flux-locked-loop circuits. A large linear flux range conduces to accurately measuring the input signal and also increasing the multiplexing factor in the time-division multiplexed(TDM) readout scheme of the TES array. In this work, we report that the linear flux range of an SQUID can be improved by using self-feedback effect. When the SQUID loop is designed to be asymmetric, a voltage-biased SQUID shows an asymmetric current–flux(I–Φ) response curve. The linear flux range is improved along the I–Φ curve with a shallow slope. The experimental results accord well with the numerical simulations. The asymmetric SQUID will be able to serve as a building block in the development of the TDM readout systems for large TES arrays.展开更多
AIM:To present computed tomography(CT) findings of different histological subtypes of parotid gland masses in detail and to establish diagnostic strategy.METHODS:From January 2009 to November 2011,56 patients were col...AIM:To present computed tomography(CT) findings of different histological subtypes of parotid gland masses in detail and to establish diagnostic strategy.METHODS:From January 2009 to November 2011,56 patients were collected through the histopathology and Picture Archiving and Communication Systems records,which revealed 5 basal cell adenoma(BCA),16 pleomorphic adenoma(PA),25 Warthin's tumor(War-T),3 Kimura's disease(KD) and 7 parotid carcinoma(PCa) cases.All the CT images were retrospectively analyzed by two radiologists in consensus,based on their description of morphology(location,number,size,margin and fibrous capsule) and enhancement patterns of masses.In addition,the diagnostic efficiency of diagnostic strategy is tested.RESULTS:War-T and BCA patients' mean age was 59.9 ± 12.6 years and 58.4 ± 18.2 years;the significant difference was seen in War-T vs PA and BCA vs PA.About 40% of War-Ts presented with bilateral multifocal lesions,a higher ratio than others.Seventy two percent of War-Ts were limited to the superficial lobe,followed by BCA 60% and PA 40%.Vessel facing sign and enlarged lymph nodes were both frequent in War-T,which respectively accounts for 84% and 76% of cases.Rapid contrast enhancement and decreases were unique for War-T.BCA and PA showed obvious delayed enhancement.The diagnostic strategy of parotid gland tumor had a good diagnostic efficiency,with high accuracy,sensitivity and specificity.CONCLUSION:Determination of the histological subtypes of parotid gland masses might be possible based on CT findings and clinical data.A diagnostic strategy with high diagnostic efficiency was established.展开更多
Intravenous leiomyomatosis(IVL),showing unusual growth patterns of uterine leiomyoma,is a rare neoplasm characterized by intravascular proliferation of a histologically benign-looking smooth muscle cell tumor mass,but...Intravenous leiomyomatosis(IVL),showing unusual growth patterns of uterine leiomyoma,is a rare neoplasm characterized by intravascular proliferation of a histologically benign-looking smooth muscle cell tumor mass,but not invading the tissue.To date,less than 300 cases have been reported and fewer than 100 cases with cardiac involvement.Imaging characteristics of IVL are still not clear so it is usually misdiagnosed before surgery.A 36-year-old woman,who had undergone hysterectomy due to hysteromyoma,presented with shortness of breath after activities.Imaging showed IVL with mass involvement of the left ovarian vein,left renal vein,left external and common iliac vein,as well as within the inferior vena cava(IVC),extending into the right atrium.The operation demonstrated that the mass had no stalk and had welldemarcated borders with the wall of the right atrium and IVC.The patient underwent a one-stage combined multidisciplinary thoraco-abdominal operation under general anesthetic.Subsequently,the pathology report confirmed IVL.IVL should be considered in a female patient presenting with an extensive mass in the right side of the heart.Imaging technology,such as echocardiogram,contrast-enhanced computed tomography and magnetic resonance imaging,can provide important information to reveal the mass,the range and path of the lesion,and relates to the surgical plan decision.Consequently,perfect and exact image examination is very necessary pre-operation.展开更多
基金Project supported by the Fund from China National Space Administration (CNSA) (Grant No. D050104)the Fund for Low Energy Gamma Ray Detection Research Based on SQUID Techniquethe Superconducting Electronics Facility (SELF) of Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences。
文摘Superconducting quantum interference devices(SQUIDs) are low-noise amplifiers that are essential for the readouts of translation edge sensors(TESs). The linear flux range is an important parameter for SQUID amplifiers, especially those controlled by high-bandwidth digital flux-locked-loop circuits. A large linear flux range conduces to accurately measuring the input signal and also increasing the multiplexing factor in the time-division multiplexed(TDM) readout scheme of the TES array. In this work, we report that the linear flux range of an SQUID can be improved by using self-feedback effect. When the SQUID loop is designed to be asymmetric, a voltage-biased SQUID shows an asymmetric current–flux(I–Φ) response curve. The linear flux range is improved along the I–Φ curve with a shallow slope. The experimental results accord well with the numerical simulations. The asymmetric SQUID will be able to serve as a building block in the development of the TDM readout systems for large TES arrays.
文摘AIM:To present computed tomography(CT) findings of different histological subtypes of parotid gland masses in detail and to establish diagnostic strategy.METHODS:From January 2009 to November 2011,56 patients were collected through the histopathology and Picture Archiving and Communication Systems records,which revealed 5 basal cell adenoma(BCA),16 pleomorphic adenoma(PA),25 Warthin's tumor(War-T),3 Kimura's disease(KD) and 7 parotid carcinoma(PCa) cases.All the CT images were retrospectively analyzed by two radiologists in consensus,based on their description of morphology(location,number,size,margin and fibrous capsule) and enhancement patterns of masses.In addition,the diagnostic efficiency of diagnostic strategy is tested.RESULTS:War-T and BCA patients' mean age was 59.9 ± 12.6 years and 58.4 ± 18.2 years;the significant difference was seen in War-T vs PA and BCA vs PA.About 40% of War-Ts presented with bilateral multifocal lesions,a higher ratio than others.Seventy two percent of War-Ts were limited to the superficial lobe,followed by BCA 60% and PA 40%.Vessel facing sign and enlarged lymph nodes were both frequent in War-T,which respectively accounts for 84% and 76% of cases.Rapid contrast enhancement and decreases were unique for War-T.BCA and PA showed obvious delayed enhancement.The diagnostic strategy of parotid gland tumor had a good diagnostic efficiency,with high accuracy,sensitivity and specificity.CONCLUSION:Determination of the histological subtypes of parotid gland masses might be possible based on CT findings and clinical data.A diagnostic strategy with high diagnostic efficiency was established.
文摘Intravenous leiomyomatosis(IVL),showing unusual growth patterns of uterine leiomyoma,is a rare neoplasm characterized by intravascular proliferation of a histologically benign-looking smooth muscle cell tumor mass,but not invading the tissue.To date,less than 300 cases have been reported and fewer than 100 cases with cardiac involvement.Imaging characteristics of IVL are still not clear so it is usually misdiagnosed before surgery.A 36-year-old woman,who had undergone hysterectomy due to hysteromyoma,presented with shortness of breath after activities.Imaging showed IVL with mass involvement of the left ovarian vein,left renal vein,left external and common iliac vein,as well as within the inferior vena cava(IVC),extending into the right atrium.The operation demonstrated that the mass had no stalk and had welldemarcated borders with the wall of the right atrium and IVC.The patient underwent a one-stage combined multidisciplinary thoraco-abdominal operation under general anesthetic.Subsequently,the pathology report confirmed IVL.IVL should be considered in a female patient presenting with an extensive mass in the right side of the heart.Imaging technology,such as echocardiogram,contrast-enhanced computed tomography and magnetic resonance imaging,can provide important information to reveal the mass,the range and path of the lesion,and relates to the surgical plan decision.Consequently,perfect and exact image examination is very necessary pre-operation.
