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1.
Nat Nanotechnol ; 18(4): 343-349, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36941357

ABSTRACT

The detection of individual quanta of light is important for quantum communication, fluorescence lifetime imaging, remote sensing and more. Due to their high detection efficiency, exceptional signal-to-noise ratio and fast recovery times, superconducting-nanowire single-photon detectors (SNSPDs) have become a critical component in these applications. However, the operation of conventional SNSPDs requires costly cryocoolers. Here we report the fabrication of two types of high-temperature superconducting nanowires. We observe linear scaling of the photon count rate on the radiation power at the telecommunications wavelength of 1.5 µm and thereby reveal single-photon operation. SNSPDs made from thin flakes of Bi2Sr2CaCu2O8+δ exhibit a single-photon response up to 25 K, and for SNSPDs from La1.55Sr0.45CuO4/La2CuO4 bilayer films, this response is observed up to 8 K. While the underlying detection mechanism is not fully understood yet, our work expands the family of materials for SNSPD technology beyond the liquid helium temperature limit and suggests that even higher operation temperatures may be reached using other high-temperature superconductors.

3.
APL Photonics ; 6(5)2021.
Article in English | MEDLINE | ID: mdl-37621960

ABSTRACT

We developed superconducting nanowire single-photon detectors based on tungsten silicide, which show saturated internal detection efficiency up to a wavelength of 10 µm. These detectors are promising for applications in the mid-infrared requiring sub-nanosecond timing, ultra-high gain stability, low dark counts, and high efficiency, such as chemical sensing, LIDAR, dark matter searches, and exoplanet spectroscopy.

4.
Nano Lett ; 20(11): 8059-8066, 2020 11 11.
Article in English | MEDLINE | ID: mdl-32965119

ABSTRACT

As the limits of traditional von Neumann computing come into view, the brain's ability to communicate vast quantities of information using low-power spikes has become an increasing source of inspiration for alternative architectures. Key to the success of these largescale neural networks is a power-efficient spiking element that is scalable and easily interfaced with traditional control electronics. In this work, we present a spiking element fabricated from superconducting nanowires that has pulse energies on the order of ∼10 aJ. We demonstrate that the device reproduces essential characteristics of biological neurons, such as a refractory period and a firing threshold. Through simulations using experimentally measured device parameters, we show how nanowire-based networks may be used for inference in image recognition and that the probabilistic nature of nanowire switching may be exploited for modeling biological processes and for applications that rely on stochasticity.


Subject(s)
Nanowires , Neural Networks, Computer , Neurons
5.
Calcif Tissue Int ; 105(2): 127-147, 2019 08.
Article in English | MEDLINE | ID: mdl-30997574

ABSTRACT

Electromagnetic fields (EMFs) have been proposed as a tool to ameliorate bone formation and healing. Despite their promising results, however, they have failed to enter routine clinical protocols to treat bone conditions where higher bone mass has to be achieved. This is no doubt also due to a fundamental lack of knowledge and understanding on their effects and the optimal settings for attaining the desired therapeutic effects. This review analysed the available in vitro and in vivo studies that assessed the effects of sinusoidal EMFs (SEMFs) on bone and bone cells, comparing the results and investigating possible mechanisms of action by which SEMFs interact with tissues and cells. The effects of SEMFs on bone have not been as thoroughly investigated as pulsed EMFs; however, abundant evidence shows that SEMFs affect the proliferation and differentiation of osteoblastic cells, acting on multiple cellular mechanisms. SEMFs have also proven to increase bone mass in rodents under normal conditions and in osteoporotic animals.


Subject(s)
Bone and Bones/cytology , Electromagnetic Fields , Osteoblasts/cytology , 3T3 Cells , Animals , Bone Morphogenetic Protein 2/metabolism , Cell Differentiation , Cell Proliferation , Cilia/metabolism , Humans , Mice , Osteoporosis , RAW 264.7 Cells , Rats , Reactive Oxygen Species/metabolism , Signal Transduction
6.
Phys Rev Appl ; 11(3)2019.
Article in English | MEDLINE | ID: mdl-32166099

ABSTRACT

The basis for superconducting electronics can broadly be divided between two technologies: the Josephson junction and the superconducting nanowire. While the Josephson junction (JJ) remains the dominant technology due to its high speed and low power dissipation, recently proposed nanowire devices offer improvements such as gain, high fanout, and compatibility with CMOS circuits. Despite these benefits, nanowire-based electronics have largely been limited to binary operations, with devices switching between the superconducting state and a high-impedance resistive state dominated by uncontrolled hotspot dynamics. Unlike the JJ, they cannot increment an output through successive switching and their operation speeds are limited by their slow thermal-reset times. Thus, there is a need for an intermediate device with the interfacing capabilities of a nanowire but a faster, moderated response allowing for modulation of the output. We present a nanowire device based on controlled fluxon transport. We show that the device is capable of responding proportionally to the strength of its input, unlike other nanowire technologies. The device can be operated to produce a multilevel output with distinguishable states, the number of which can be tuned by circuit parameters. Agreement between experimental results and electrothermal circuit simulations demonstrates that the device is classical and may be readily engineered for applications including use as a multilevel memory.

7.
G Chir ; 34(11-12): 326-31, 2013.
Article in English | MEDLINE | ID: mdl-24342162

ABSTRACT

Renal angiomyolipoma (AML) is a benign mesenchymal tumour. AML often leads to haemorrhagic complications such as retroperitoneal haematoma. Treatment varies from case to case, ranging from minimally invasive approaches such as selective embolization of the renal artery to invasive wedge resection, partial nephrectomy or, in more severe cases, radical nephrectomy. Here we report a case of retroperitoneal haematoma secondary to AML, treated with conservative approach by super-selective embolization of the lower-pole segmental renal artery.


Subject(s)
Angiomyolipoma/therapy , Embolization, Therapeutic , Kidney Neoplasms/therapy , Nephrectomy , Adult , Angiomyolipoma/surgery , Female , Humans , Kidney Neoplasms/surgery
8.
G Chir ; 34(5-6): 161-3, 2013.
Article in English | MEDLINE | ID: mdl-23837954

ABSTRACT

Hamartoma is a benign tumor-like malformation characterized by a focal mixture of mature cells and tissues normally present in affected area. The hamartoma of the breast is rare. We report a case in an asymptomatic young woman coming to our attention for a left breast lesion detected by ultrasound screening.


Subject(s)
Breast Diseases , Hamartoma , Adult , Breast Diseases/diagnosis , Female , Hamartoma/diagnosis , Humans
9.
G Chir ; 34(9-10): 254-6, 2013.
Article in English | MEDLINE | ID: mdl-24629809

ABSTRACT

Neoadjuvant chemotherapy (NACT) in locally advanced breast tumors may allow an adequate control of the disease impossible with surgery alone. Moreover, NACT increases the chance of breast-conserving surgery. Between 2008 and 2012, we treated with NACT 83 patients with locally advanced breast cancer. We report the preliminary results evaluating the impact of NACT on the type of surgery.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/surgery , Mastectomy, Segmental , Neoadjuvant Therapy/methods , Breast Neoplasms/pathology , Chemotherapy, Adjuvant/methods , Female , Humans , Neoplasm Staging , Treatment Outcome
10.
Radiol Med ; 117(4): 679-89, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22231572

ABSTRACT

PURPOSE: This study was undertaken to compare the effectiveness of ultrasound-guided Hartmann's solution enema (US-E) and radiological liquid enema (RX-E) in reducing idiopathic ileocecocolic intussusceptions in relation to patient age and symptom duration. MATERIALS AND METHODS: The study group consisted of 42 patients with idiopathic ileocecocolic intussusception treated with US-E (20 patients) or RX-E (23 patients), with one patient undergoing both procedures owing to recurrence. Patients were divided into subgroups according to age (<6 months, 6-12 months, >12 months) and symptom duration (<12 h, 12-24 h, >24 h). RESULTS: Complete reduction was achieved in 15/20 patients treated with US-E (75%) and in 10/23 treated with RX-E (43.5%) (p=ns). Recurrence was observed in 1/20 US-E and 0/23 RX-E (p=ns) patients. No complications were encountered. US-E had a significantly higher success rate than RX-E in patients >12 months (p=0.0063) and with symptom duration >24 h (p=0.0361). No differences were found in the other subgroups (p=ns). CONCLUSIONS: US-E and RX-E are procedures of comparable value and safety in reducing idiopathic intussusception. US-E seems to be more effective in patients >12 months or with symptom duration >24 h. As US-E avoids radiation exposure, it should be considered the first-choice procedure for reducing idiopathic ileocecocolic intussusception, particularly in these two subgroups of patients.


Subject(s)
Enema/methods , Ileal Diseases/therapy , Intussusception/therapy , Isotonic Solutions/therapeutic use , Ultrasonography, Interventional , Chi-Square Distribution , Child , Child, Preschool , Contrast Media/administration & dosage , Diatrizoate Meglumine/administration & dosage , Enema/adverse effects , Female , Humans , Hydrostatic Pressure , Ileal Diseases/diagnostic imaging , Infant , Intussusception/diagnostic imaging , Male , Radiography, Interventional , Recurrence , Retrospective Studies , Treatment Outcome
11.
J Ultrasound ; 14(1): 7-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-23396992

ABSTRACT

INTRODUCTION: Inflammatory myofibroblastic tumor (IMT) is a benign solid tumor of uncertain etiology. MATERIALS AND METHODS: We report a case of a 4-year-old Down syndrome affected child, who had a pancreatic mass identified by ultrasonography (US) and confirmed by computed tomography (CT). RESULTS: Monitoring of IMT was performed by serial US studies, and at follow-up after 4 years there was no relapse. DISCUSSION: As radical removal of the lesion was not possible, the patient was successfully treated with nonsteroidal anti-inflammatory drugs (NSAIDs). It was decided to monitor the lesion by serial US in order to reduce the number of CT examinations and thereby avoid excessive exposure to ionizing radiation. It is widely reported in the literature that repeated CT scans are associated with increased exposure to radiation which may cause cancer, a fact which should not be overlooked in children.

12.
Ann Oncol ; 18(8): 1348-53, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17470449

ABSTRACT

BACKGROUND: A prospective phase II study was conducted to evaluate the efficacy and toxicity of the combination docetaxel (Taxotere) (DTX) and oxaliplatin (OXA) in ovarian cancer patients recurring after a platinum-free interval (PFI) >12 months. PATIENTS AND METHODS: DTX, 75 mg/m(2), was administered by 60 min i.v. infusion, followed by OXA, 100 mg/m(2), given by a 2 h i.v., on day 1 every 21 days. RESULTS: From October 2003 to June 2006, 43 ovarian cancer patients were enrolled. Median PFI was 26 months. All patients were available for response evaluation: 17 complete responses and 12 partial responses were registered, for an overall response rate of 67.4%. The median response duration was 10 months. Stable disease was documented in 11 patients (median duration = 5.5 months). The median time to progression and overall survival were 14 and 28 months. A total of 259 courses were administered. Grade 3-4 leukopenia was documented in 32.5% of the patients, while no case of severe anemia and thrombocytopenia was observed. Grade 3-4 neurotoxicity and grade 2 alopecia were observed in 9.3% and 34.9% of cases, respectively. CONCLUSION: DTX/OXA combination is an active regimen with a favorable toxicity profile, for treatment of recurrent platinum-sensitive ovarian cancer patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Ovarian Neoplasms/drug therapy , Adult , Aged , Disease-Free Survival , Docetaxel , Female , Humans , Middle Aged , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Ovarian Neoplasms/mortality , Oxaliplatin , Taxoids/administration & dosage , Taxoids/adverse effects , Treatment Outcome
13.
G Ital Med Lav Ergon ; 29(3 Suppl B): B5-17, 2007.
Article in Italian | MEDLINE | ID: mdl-18575353

ABSTRACT

A large proportion of patients hospitalised for severe neuromotor disorders are supported during the in-hospital rehabilitation program by family members. To target interventions of psychological support for these caregivers it can be of help to identify the causes of caregiver burden or specific needs. Anxiety and depression are common in caregivers and constitute, together with emotional distress caused by loneliness and reduced social activities, an important part of the caregiving burden. This paper presents results emerging from a clinical intervention of psychological support offered to caregivers of neuromotor patients, mainly post-stroke, who were undergoing a course of in-hospital rehabilitation. A psychometric assessment was carried out on a sample of 50 caregivers, spouses or children, at the beginning and end of the in-hospital rehabilitation period. The following questionnaires were used: the Revised Anxiety and Depression Scale (RADS), measuring anxiety and depression, the Caregiver Need Assessment (CNA), assessing needs related to the assisted patient, and the Family Strain Questionnaire (FSQ) for a broader assessment of the problems faced by caregivers. The Functional Independence Measure (FIM) was completed by the medical doctor. A significant reduction was found, between the beginning and end of the rehabilitation period, in the needs related to patient care on the CNA (p < 0.001). Caregiver females, in contrast to males, showed an improvement in mood compared to the beginning of the rehabilitation period (p < 0.05). About half of the sample had, at the beginning, a marked clinical level of anxiety while 22% of caregivers had a marked clinical level of depression. Caregivers who received intense psychological support, i.e. at least one interview with the psychologist per week, showed, in contrast to those who received 3-4 interviews during the entire rehabilitation period, a decline in thoughts of death (p < 0.05) and, in cases where baseline anxiety was above the clinical cut-off, a reduced level of anxiety (p < 0.05). At the beginning of rehabilitation, there emerged: higher anxiety scores in caregivers who live with their patient (p < 0.05) compared to those living alone or with others; an increase in depression scores in inverse proportion to the patient's age (p = 0.01); higher scores of emotional stress in spouses (p < 0.05) compared to children and in caregivers of patients with left hemisphere deficits (p < 0.05); a greater need for knowledge about the disease (p < 0.001) and more thoughts of death (p < 0.05) in caregivers of female patients. These characteristics may be considered "alarm signals" that should alert hospital medical staff to the need to seek psychological help for the caregiver. At the end of rehabilitation, a greater degree of psychological strain was observed in caregivers of patients with severe disability. High needs related to the assisted patient (p < 0.01), high scores of emotional stress (p < 0.05), problems of social involvement (p < 0.05) and thoughts of death about the patient (p < 0.05) were found in caregivers of patients who had persisting high motor disability or who were admitted for consequences of a left hemisphere lesion. High depression scores were also found in caregivers of patients with high residual cognitive disability (p < 0.05). This psychometric evaluation makes it possible to tailor the psychological support offered to the needs of each individual caregiver both during rehabilitation and in relation to eventual future developments. A multidisciplinary team approach to the caregiver can thus lead to a general reduction of caregiver strain.


Subject(s)
Caregivers/psychology , Neuromuscular Diseases/rehabilitation , Adaptation, Psychological , Adult , Aged , Aged, 80 and over , Anxiety/etiology , Counseling/methods , Depression/etiology , Female , Humans , Inpatients , Interdisciplinary Communication , Male , Middle Aged , Psychiatric Status Rating Scales , Psychometrics , Psychotherapy/methods , Social Isolation , Stress, Psychological/etiology , Stroke Rehabilitation , Surveys and Questionnaires
14.
J Ambul Care Manage ; 21(1): 35-43, 1998 Jan.
Article in English | MEDLINE | ID: mdl-10181338

ABSTRACT

Two studies were conducted that assessed health perceptions and functional health status among an urban, low-income population in the southeastern region of the United States. The first study was conducted with 176 hospitalized indigent patients prior to discharge from a county hospital. Patients were administered the Short Form-36 (SF-36) health status questionnaire and two additional questions regarding perceptions of health. The second study was conducted in the same geographic region with a nonhospitalized, low-income population. The SF-36 was administered by telephone to 546 randomly selected interview respondents. The results demonstrated consistent differences between black and white respondents in referents for self-perceived health. It is suggested that health expectations and perceptions may be indicative of the cultural, contextual, and social-political factors that affect the lives of this urban, low income population. The validity of global single-item health indicators for use among low-income populations is questioned. Further research is needed to develop patient-based measures that accurately reflect the meanings and values of low-income patient groups.


Subject(s)
Attitude to Health , Black or African American/statistics & numerical data , Health Status Indicators , White People/statistics & numerical data , Adolescent , Adult , Black or African American/psychology , Aged , Female , Health Surveys , Humans , Male , Middle Aged , Poverty , Reproducibility of Results , Self Concept , Southeastern United States , Urban Population , White People/psychology
15.
Childs Nerv Syst ; 7(6): 353-5, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1764712

ABSTRACT

A giant aneurysm of the right callosomarginal artery is reported in a 3-month-old child. This location is rare: including our case reported here, only three cases have been described. Clinicoradiological findings are presented and the surgical procedure is illustrated.


Subject(s)
Intracranial Aneurysm/diagnosis , Female , Humans , Infant , Intracranial Aneurysm/surgery , Magnetic Resonance Imaging , Neurologic Examination , Parietal Lobe , Tomography, X-Ray Computed
16.
Childs Nerv Syst ; 6(7): 379-82, 1990 Nov.
Article in English | MEDLINE | ID: mdl-1669245

ABSTRACT

The criteria by which the operative approaches to craniopharyngioma are chosen are still controversial. The authors performed a retrospective analysis in 32 patients with craniopharyngioma who were surgically treated. Results of neurological and psychological tests administered during the follow-up period were correlated with the surgical approach. On the basis of these preliminary data and a maximum follow-up period of 10 years, the authors conclude that the subfrontal approach to the craniopharyngioma and partial removal of its solid part appears to be associated with a lower morbidity rate and minor frontal lobe disorders.


Subject(s)
Brain Damage, Chronic/etiology , Child Behavior Disorders/etiology , Craniopharyngioma/surgery , Hypophysectomy/methods , Neurologic Examination , Pituitary Neoplasms/surgery , Postoperative Complications/etiology , Adolescent , Child , Child, Preschool , Combined Modality Therapy , Craniopharyngioma/radiotherapy , Female , Follow-Up Studies , Humans , Infant , Male , Neuropsychological Tests , Pituitary Irradiation , Pituitary Neoplasms/radiotherapy , Retrospective Studies
17.
Childs Nerv Syst ; 5(3): 153-5, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2758427

ABSTRACT

In order to characterize neurological, intellectual and behavioral sequelae better after surgical treatment of brain abscess in childhood, 32 children were studied over a 10-year time span after treatment of a brain abscess. Depending on the clinical condition, surgical treatment consisted of simple aspiration through a burr hole or of total excision after craniotomy. There were only 3 postoperative deaths (9%). The scheduled time for long-term follow-up was 3 years after surgery. The patient assessment included information concerning the presence of seizures, accurate neurological examination, an EEG, and a battery of intellectual tests to evaluate the presence of behavioral-mental deficits. Late seizures developed in 7 of the 29 survivors. Five patients presented permanent hemiparesis after surgical treatment. It is noteworthy that the intellectual impairment observed was more severe in younger patients, while the behavioral disturbances were more marked in school-age children.


Subject(s)
Brain Abscess/surgery , Child Behavior Disorders/etiology , Nervous System Diseases/etiology , Postoperative Complications , Adolescent , Brain Abscess/pathology , Child , Child, Preschool , Electroencephalography , Epilepsy/etiology , Epilepsy/physiopathology , Female , Humans , Infant , Intelligence , Male
18.
Childs Nerv Syst ; 3(2): 81-4, 1987.
Article in English | MEDLINE | ID: mdl-3621232

ABSTRACT

Medulloblastoma constituted 28% of brain neoplasms among children referred to the Santobono Children's Hospital of Naples from 1973 through October 1984. The authors summarize their experience with 68 cases of medulloblastoma, which were managed with a multimodal institutional protocol involving surgery, chemotherapy and radiation therapy. The evolution of modern management is discussed, and particular attention is directed to the factors affecting the prognosis.


Subject(s)
Cerebellar Neoplasms/therapy , Medulloblastoma/therapy , Adolescent , Cerebellar Neoplasms/mortality , Child , Child, Preschool , Combined Modality Therapy , Female , Humans , Infant , Male , Medulloblastoma/mortality , Neoplasm Recurrence, Local , Prognosis , Quality of Life , Time Factors
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