Prevention and early management of carotid blowout syndrome for patients receiving head and neck salvage boron neutron capture therapy (BNCT)

Background/purpose The incidence rate of oral and pharyngeal cancers in Taiwan has increased gradually over the past few decades. The standard treatment strategy for oral and pharyngeal cancers includes surgery or radiotherapy, with concurrent chemotherapy in certain types of tumors. Unfortunately, in-field recurrence is sometimes inexorable. Furthermore, re-irradiation of the recurrence site may cause severe complications due to the tolerance of normal tissue to radiation therapy. One fatal complication is carotid blowout syndrome (CBS). Boron neutron capture therapy (BNCT) is a new modality of radiation therapy, which is also mentioned as targeted radiotherapy. It is a feasible treatment that has the potential to spare normal tissue from being damaged by irradiation while simultaneously treating the primary tumor. In this presentation, we will share our experience with BNCT in treating recurrent head and neck cancers, as well as the prevention and management of CBS. Materials and methods We evaluated 4 patients with head and neck cancers treated by BNCT in Taiwan. All patients had undergone surgery previously and had received postoperative concurrent chemoradiotherapy. Results The 4 patients in this study were diagnosed with head and neck malignancies. The median follow-up period after the first course of BNCT was 15.1 months. After BNCT, 2 patients developed impending CBS, and 1 of them died. The remaining 3 patients survived until the last date of follow-up. Conclusion Pre-BNCT carotid artery evaluation through computed tomography angiography and early intervention if necessary is crucial when treating patients with recurrent head and neck cancers by BNCT

A Study of Antibioactivity of Nanosilver Colloid and Silver Ion Solution

The colloidal silver solution was successfully prepared in dielectric fluid by using electrical spark discharge (ESD) without any surfactants. It does not require the toxic chemical agents in the process, which may affect the effectiveness of nanosilver colloid as an antibacterial agent. Nanocolloidal silver produced by ESD is characterized as low cost, zero environmental pollution, continuous, and rapid mass production process. In order to test the effect of antibioactivity, nanosilver dough was tested; the silver nanofluid was prepared by ESD machine, made into dough at different concentrations, and fermented for three hours in order to observe changes in the diameter of the dough. The results showed that the effect of effectiveness of nanosilver at the concentration of 100 ppm was weak, whereas the effect of 60 ppm silver ion (100 ppm AgNO3) was significant, as the dissociation rate of silver ion concentration correlates to the antibioactivity

Task-Switching Performance Improvements After Tai Chi Chuan Training Are Associated With Greater Prefrontal Activation in Older Adults

Studies have shown that Tai Chi Chuan (TCC) training has benefits on task-switching ability. However, the neural correlates underlying the effects of TCC training on task-switching ability remain unclear. Using task-related functional magnetic resonance imaging (fMRI) with a numerical Stroop paradigm, we investigated changes of prefrontal brain activation and behavioral performance during task-switching before and after TCC training and examined the relationships between changes in brain activation and task-switching behavioral performance. Cognitively normal older adults were randomly assigned to either the TCC or control (CON) group. Over a 12-week period, the TCC group received three 60-min sessions of Yang-style TCC training weekly, whereas the CON group only received one telephone consultation biweekly and did not alter their life style. All participants underwent assessments of physical functions and neuropsychological functions of task-switching, and fMRI scans, before and after the intervention. Twenty-six (TCC, N = 16; CON, N = 10) participants completed the entire experimental procedure. We found significant group by time interaction effects on behavioral and brain activation measures. Specifically, the TCC group showed improved physical function, decreased errors on task-switching performance, and increased left superior frontal activation for Switch > Non-switch contrast from pre- to post-intervention, that were not seen in the CON group. Intriguingly, TCC participants with greater prefrontal activation increases in the switch condition from pre- to post-intervention presented greater reductions in task-switching errors. These findings suggest that TCC training could potentially provide benefits to some, although not all, older adults to enhance the function of their prefrontal activations during task-switching

Trends in prevalence of blindness and distance and near vision impairment over 30 years: an analysis for the Global Burden of Disease Study

Background: To contribute to the WHO initiative, VISION 2020: The Right to Sight, an assessment of global vision impairment in 2020 and temporal change is needed. We aimed to extensively update estimates of global vision loss burden, presenting estimates for 2020, temporal change over three decades between 1990–2020, and forecasts for 2050. Methods: We did a systematic review and meta-analysis of population-based surveys of eye disease from January, 1980, to October, 2018. Only studies with samples representative of the population and with clearly defined visual acuity testing protocols were included. We fitted hierarchical models to estimate 2020 prevalence (with 95% uncertainty intervals [UIs]) of mild vision impairment (presenting visual acuity ≥6/18 and <6/12), moderate and severe vision impairment (<6/18 to 3/60), and blindness (<3/60 or less than 10° visual field around central fixation); and vision impairment from uncorrected presbyopia (presenting near vision <N6 or <N8 at 40 cm where best-corrected distance visual acuity is ≥6/12). We forecast estimates of vision loss up to 2050. Findings: In 2020, an estimated 43·3 million (95% UI 37·6–48·4) people were blind, of whom 23·9 million (55%; 20·8–26·8) were estimated to be female. We estimated 295 million (267–325) people to have moderate and severe vision impairment, of whom 163 million (55%; 147–179) were female; 258 million (233–285) to have mild vision impairment, of whom 142 million (55%; 128–157) were female; and 510 million (371–667) to have visual impairment from uncorrected presbyopia, of whom 280 million (55%; 205–365) were female. Globally, between 1990 and 2020, among adults aged 50 years or older, age-standardised prevalence of blindness decreased by 28·5% (–29·4 to −27·7) and prevalence of mild vision impairment decreased slightly (–0·3%, −0·8 to −0·2), whereas prevalence of moderate and severe vision impairment increased slightly (2·5%, 1·9 to 3·2; insufficient data were available to calculate this statistic for vision impairment from uncorrected presbyopia). In this period, the number of people who were blind increased by 50·6% (47·8 to 53·4) and the number with moderate and severe vision impairment increased by 91·7% (87·6 to 95·8). By 2050, we predict 61·0 million (52·9 to 69·3) people will be blind, 474 million (428 to 518) will have moderate and severe vision impairment, 360 million (322 to 400) will have mild vision impairment, and 866 million (629 to 1150) will have uncorrected presbyopia. Interpretation: Age-adjusted prevalence of blindness has reduced over the past three decades, yet due to population growth, progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

The microstructural and magnetic characterization in NiFe/CoO/Co trilayers and ion-beam bombarded NiFe/Fe-oxide bilayers

本研究利用雙離子束濺鍍系統製備(1)鎳鐵/氧化鈷/鈷三層薄膜，探討不同氧化鈷厚度對交換偏壓效應之影響；(2)鎳鐵/氧化鐵雙層薄膜，探討離子束轟擊氧化鐵表面對鎳鐵/氧化鐵雙層薄膜之磁性質影響。 由X光繞射儀及電子顯微鏡分析顯示：鎳鐵/氧化鈷/鈷三層薄膜分別由面心立方之鎳鐵，鹽岩結構之氧化鈷及六方最密堆積之鈷所組成。磁性質研究結果顯示：在室溫下，鎳鐵/氧化鈷/鈷三層薄膜中氧化鈷厚度為5奈米，其磁滯曲線呈現台階形狀。經由場冷至10 K之鎳鐵/氧化鈷/鈷三層薄膜中，氧化鈷厚度為5奈米之樣品具有最大之矯頑磁力（Ｈc ~ 286 Oe），而氧化鈷厚度為12奈米之樣品具有最大之交換偏壓場（Ｈex ~ -143 Oe）。磁化量對溫度之相依性（零場冷及場冷）研究顯示：鎳鐵/氧化鈷/鈷三層薄膜均具有類似自旋玻璃之行為，其不同之阻隔溫度及不可逆溫度與氧化鈷厚度造成之鐵磁/反鐵磁耦合有關。此外，極化中子反射儀研究之初步結果(如：自旋非對稱與自旋翻轉機制)顯示：磁化翻轉機制隨著外加磁場改變而不同。 在離子束轟擊氧化鐵表面之鎳鐵/氧化鐵雙層薄膜結構分析(X光繞射儀、電子顯微鏡)結果顯示：鎳鐵/氧化鐵雙層薄膜均含有面心立方結構隻鎳鐵、剛玉型六方最密堆積結構之氧化鐵，並由電子能譜化學分析儀證實鎳鐵/氧化鐵雙層薄膜界面無擴散現象。磁性質分析結果顯示：室溫下，鎳鐵/氧化鐵雙層薄膜無明顯之交換偏壓。鎳鐵/氧化鐵雙層薄膜由室溫場冷到160 K時，經70 V轟擊後之樣品磁異向性降低，使矯頑磁力(Hc ~ 18 Oe)較未轟擊之樣品小。場冷至10 K下，未經離子束轟擊之鎳鐵/氧化鐵雙層膜具有最大之矯頑磁力約204 Oe，而經70 V轟擊之樣品具有最大之交換偏壓(Hex ~ -261 Oe)。最後，由磁化量對溫度之相依性結果顯示：經70 V轟擊後之鎳鐵/氧化鐵雙層薄膜具有最高之阻隔溫度(TB ~ 100 K)，而未經離子束轟擊之樣品則具有最高之不可逆溫度(Tirr. ~ 250 K)。Exchange bias (EB) is the term used to describe the unidirectional anisotropy found in a ferromagnet (FM) exchanged-coupled to an antiferromagnet (AFM). In this research, a dual ion-beam deposition technique was used to prepare the NiFe/CoO/Co trilayers with different CoO thicknesss and NiFe/Fe-oxide bilayers for ion-beam bombardment. Results have shown that the trilayer consisted of f.c.c. NiFe, roak-salt CoO, and h.c.p. Co structures. At room temperature, the NiFe/CoO/Co trilayers exhibited soft magnetic properties with coercivity close to those of reference single NiFe and Co layer, However, a step with enhanced Hc was observed in a NiFe/CoO(5 nm)/Co trilayer. The exchange bias coupling interaction between NiFe/CoO and CoO/Co was set in when field-cooling the trilayers below the Neel temperature of CoO down to 10 K. A largest exchange bias field (Hex ~ -143 Oe) resulting from competition between top and bottom FM/AFM interfaces was found in a NiFe/CoO(12 nm)/Co trilayer. In the ZFC/FC results, the NiFe/CoO/Co trilayers exhibited spin-glass-like behavior, while the different block temperature and irreversible temperature were caused by ferromagnetic/ antiferromagnetic coupling with different cobalt oxide thickness. Moreover, the preliminary PNR data were consistent with the hysteresis loop. The exchange coupling effects in NiFe/Fe-oxide bilayers consisted of f.c.c. NiFe and corundum h.c.p. α-Fe2O3 structures, there were no intermixing at ferromagnetic/ antiferromagnetic surface as characterized by Electron Spectroscopy for Chemical Analysis (ESCA). Without the exchange bias at 298 K, and after 70 V Ar ion bombarded observed decrease in Hc after field cooling (FC) to 160 K is mainly attributed to a reduced effective magnetic anisotropy. The hysteresis loops were measured parallel to the film surface after being field cooled from room temperature down to 10 K at 20 kOe. The enhanced coercivity (Hc ~ 204 Oe) for not bombarded NiFe/Fe-oxide bilayer and a maximum exchange bias (Hex ~ -261 Oe) was discovered at after 70 V bombarded. The results of ZFC/FC were discovered a largest block temperature (TB ~ 110 K) with 70 V bombarded, whereas the largest irreversible temperature (Tirr.) about 250 K observed at the NiFe/Fe-oxide bilayer at sample of not bombarded.目 錄 致 謝 I 摘 要 II Abstract III 目 錄 IV 表 索 引 VI 圖 索 引 VIII 第一章、緒論 1 1-1、前言 1 1-2、應用 2 1-2-1、磁阻式隨機記憶體(MRAM) 2 1-2-2、巨磁阻(GMR) 3 1-2-3、穿隧磁阻(TMR) 4 1-2-4、自旋閥(Spin-valve)結構元件 5 1-3、研究動機與目的 6 1-4、第一章參考文獻 9 第二章、基礎理論與文獻回顧 10 2-1、雙離子束濺鍍系統之原理及應用 10 2-1-1、Kaufman離子源 10 2-1-2、End-Hall離子源 12 2-2、磁性材料 14 2-2-1、磁性物質種類與簡介 14 2-2-2、磁異向性之介紹 19 2-2-3、磁電阻 21 2-2-4、異向性磁阻 22 2-3、交換偏壓 23 2-3-1、交換耦合機制 23 2-3-2、零場冷與場冷之磁滯曲線比較 24 2-3-3、理論模型 25 2-4、文獻回顧 30 2-4-1、反鐵磁層厚度效應 30 2-4-2、鐵磁層厚度與溫度之交換耦合效應 34 2-4-3、單層及三層膜磁電阻變化 36 2-4-4、磁化量(M)與溫度(T)之關係 37 2-4-5、離子束轟擊效應 38 2-4-6、X光繞射分析 39 2-4-7、電子能譜化學分析 40 2-4-8、極性中子反射量測 42 2-5、第二章參考文獻 46 第三章、實驗 48 3-1、實驗架構 48 3-2、材料選用 50 3-3、薄膜製備 55 3-3-1、基板前處理 55 3-3-2、鍍膜參數 55 3-4、分析儀器原理之簡介 57 3-4-1、X光繞射儀(XRD) 57 3-4-2、穿透式電子顯微鏡(TEM) 60 3-4-3、震動樣品磁力計(VSM) 64 3-4-4、超導量子干涉儀(SQUID) 66 3-4-5、磁力顯微鏡(MFM) 68 3-4-6、磁電阻量測(MR) 70 3-4-7、電子能譜化學分析儀(ESCA) 72 3-4-8、極化中子反射儀(PNR) 74 3-5、第三章參考文獻 77 第四章、結果與討論 78 4-1、改變反鐵磁層厚度之研究 78 4-1-1、X光繞射分析(XRD) 78 4-1-2、穿透式電子顯微鏡(TEM)微結構分析 80 4-1-3、震動樣品磁力計量測(VSM) 87 4-1-4、超導量子干涉儀(SQUID)磁性量測 92 4-1-5、原子力顯微鏡(AFM)及磁力顯微鏡(MFM)分析 99 4-1-6、磁電阻(MR)量測 101 4-1-7、極化中子反射儀(PNR)量測 106 4-2、離子束轟擊反鐵磁層之研究 109 4-2-1、X光繞射分析(XRD) 109 4-2-2、穿透式電子顯微鏡(TEM)微結構分析 111 4-2-3、電子能譜化學分析儀(ESCA) 114 4-2-4、震動樣品磁力計量測(VSM) 117 4-2-5、超導量子干涉儀(SQUID)磁性量測 119 4-2-6、原子力顯微鏡(AFM)及磁力顯微鏡(MFM)分析 123 4-3、第四章參考文獻 124 第五章、結論 126 i、鎳鐵/氧化鈷/鈷三層薄膜 126 ii、鎳鐵/氧化鐵雙層膜 12

Unusual Exchange Bias Effects Induced in NiFe/Mn Thin Films via Ion-beam Bombardment: Superlattice vs. Nanocomposite

The interplay between interlayer coupling and exchange bias coupling in [NiFe/Mn] multilayerbasedthin films was investigated by using ion-beam bombardment during deposition to control theconfigurations from superlattice to nanocomposite or hybrid-structured thin films. Results showedthat well-defined interfaces in the superlattice [NiFe/Mn] thin film exhibited an interlayer couplingbehavior. In contrast, an enhanced coercivity was observed in the nanocomposite [NiFe-Mn] thinfilm. However, the hybrid [NiFe-Mn]/[NiFe/Mn] thin film with an intermixed NiFeMn alloyed filmcomponent gave rise to unusual positive exchange bias coupling

Dispersion in double-porosity unsaturated medium: from experiment towards modeling by homogenization

International audienceThis study presents a macroscopic double-porosity dispersion model for unsaturated water flow conditions, developed by asymptotic homogenization method. The model shows a coupling between the concentrations in the micro- and macro-porosity domains (local non-equilibrium), resulting in an early breakthrough and a long tail effects. A series of one-dimensional dispersion experiments of passive tracer under unsaturated steady-state flow conditions in a physical model of double-porosity material, was performed. An excellent agreement between the numerical simulations and the experiments proves good predictive capacity of the developed model

Neurofibromatosis type 2 initially presenting as a preauricular mass: a case report

Abstract Neurofibromatosis type 2 (NF2) is a rare genetic disease involving multiple tumors of the central and peripheral nervous systems. Most patients with NF2 have bilateral vestibular schwannomas; nonvestibular schwannomas may also develop. While the majority of patients may present with hearing impairment, tinnitus, dizziness and balance disorders, some may present with cutaneous manifestations. We describe the case of a 20-year-old man who initially presented with a solitary subcutaneous painless nodule in the left preauricular area without any other symptoms. He received excisional biopsy for the preauricular mass and the pathologic diagnosis was schwannoma. Magnetic resonance imaging of brain and neck revealed multiple mass lesions over the bilateral cerebellopontine angle cisterns, extending to the bilateral internal auditory canals, bilateral cervical neuroforamens, cervical and upper thoracic spinal canals, and left posterior neck. The patient was diagnosed with NF2 according to the clinical criteria. He underwent gamma knife stereotactic radiosurgery for bilateral vestibular schwannomas and is now under regular monitoring. Conclusion NF2 patients may present with an isolated solitary cutaneous schwannoma with no other associated clinical findings. Further assessment is thus warranted in young patients presenting with a peripheral schwannoma despite absence of other clinical findings