Mode B Ultrasound in the Study of the Posterior Segment in the Medical Clinic “Marie Curie” in Bamako

Introduction: The study of the posterior segment of the eye has nowadays become one of the most frequent indications for diagnostic ultrasound in the ophthalmological field. The objective of this work is to contribute to the improvement of the diagnostic management of pathologies of the posterior segment of the eye in the radiology department of the medical clinic “Marie Curie” in Bamako. Material and Methods: This was a cross-sectional study carried out in the medical imaging department from January 2020 to January 2022. It concerned all patients who presented for the study of the ocular posterior segment on ultrasound. Results: Fifty-two (52) patients out of a total of 109 were included in the study, i.e. a frequency of 47.70%. The average age was 33.90 with the extremes ranging from 05 years to 75 years. The male sex dominated with a frequency of 69.23%. Ocular ultrasound was prescribed mainly by ophthalmologists (100%). In the study of the posterior segment, preoperative assessment represented the most frequent indications with respectively 55.76% and 23.10%. Retinal detachment and vitreous hemorrhage were the most found lesions on ultrasound with 50% and 34.61% respectively. Conclusion: Ocular ultrasound is accessible in Bamako and has allowed the study of the posterior segment of the eye. It occupies an important place in the study and management of ocular pathologies of the posterior segment.

Ultrasound in Ti-Rads Classification of Thyroid Nodules at the Marie Curie Medical Clinic

Introduction: A thyroid nodule is a localized hypertrophy within the thyroid parenchyma. The aim of our study was to study the benefit of ultrasound in the Ti-rads classification of thyroid nodules. Methodology: This was a prospective study with a descriptive aim, with prospective collection, which took place over a period of 17 months at the “Marie Curie” medical clinic. The ultrasound machine used was a Voluson E8 from 2011 and the examinations were carried out by two radiologists and two experienced sonographers. The parameters studied were sociodemographic data;clinical data and ultrasound aspects of the Ti-rads classification in the management of nodules. Results: We collected 235 patients out of 738 patients referred to the service for a cervical ultrasound, i.e. a frequency of 31.84% of cases. There was a female predominance with 95.7% of cases and a sex ratio of 0.04. The average age of our patients was 50 years. We found on cervical ultrasound: Isthmo-lobar glandular hyperplasia in 99 patients, i.e. a frequency of 42.1%. The Ti-rads 3 classification was the most represented in 69.4% of cases. The benignity criterion represented 85.6% of cases in our patients and the malignancy criterion represented 14.4% of cases. Conclusion: The precise description of a thyroid nodule provided by ultrasound (Ti-rads) is essential in the management of nodules.

Controllable high Curie temperature through 5d transition metal atom doping in CrI_(3)

Two-dimensional(2D) CrI_(3) is a ferromagnetic semiconductor with potential for applications in spintronics. However,its low Curie temperature(T_(c)) hinders realistic applications of CrI3. Based on first-principles calculations, 5d transition metal(TM) atom doping of CrI_(3)(TM@CrI_(3)) is a universally effective way to increase T_(c), which stems from the increased magnetic moment induced by doping with TM atoms. T_(c) of W@CrI_(3) reaches 254 K, nearly six times higher than that of the host CrI_(3). When the doping concentration of W atoms is increased to above 5.9%, W@CrI_(3) shows room-temperature ferromagnetism. Intriguingly, the large magnetic anisotropy energy of W@CrI_(3) can stabilize the long-range ferromagnetic order. Moreover, TM@CrI_(3) has a strong ferromagnetic stability. All TM@CrI_(3) change from a semiconductor to a halfmetal, except doping with Au atom. These results provide information relevant to potential applications of CrI_(3) monolayers in spintronics.

On a Heuristic Point of View about the Generalization of Curie Law to Cosmic Higgs Fields with the Casimir Effect

Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform into paramagnetic substances. Below the Curie temperature, a material remains ferromagnetic;above it, the material becomes paramagnetic, with its magnetic field easily influenced by external magnetic fileds. For example, the Curie temperature of iron (Fe) is 1043 K, while that of neodymium magnets ranges from 583 to 673 K. From both physics and mathematics perspectives, examining the temperature properties of materials is essential, as it provides valuable insights into their electromagnetic and thermodynamic behaviors. This paper makes a bold assumption and, for the first time, carefully verifies the existence of a Casimir temperature at 0.00206 K under conditions of one-atomic spacing.

Determination of Curie Point Depth and Heat Flow Using Airborne Magnetic Data over the Kom-Ombo and Nuqra Basins, Southern Eastern Desert, Egypt

The Kom-Ombo and Nuqra basins in southern Egypt have recently been discovered as potential hydrocarbon basins. The lack of information about the geothermal gradient and heat flow in the study area gives importance to studying the heat flow and the geothermal gradient. Several studies were carried out to investigate the geothermal analyses of the northwestern desert, as well as the west and east of the Nile River, using density, compressive wave velocity, and bottom hole temperature (BHT) measured from deep oil wells. This research relies on spectral analysis of airborne magnetic survey data in the Kom-Ombo and Nuqra basins in order to estimate the geothermal gradient based on calculating the depth to the bottom of the magnetic source that caused the occurrence of these magnetic deviations. This depth is equal to the CPD, at which the material loses its magnetic polarisation. This method is fast and gives satisfactory results. Usually, it can be applied as a reconnaissance technique for geothermal exploration targets due to the abundance of magnetic data. The depth of the top (Zt) and centroid (Z0) of the magnetic source bodies was calculated for the 32 windows representing the study area using spectral analysis of airborne magnetic data. The curie-isotherm depth, geothermal gradient, and heat flow maps were constructed for the study area. The results showed that the CPD in the study area ranges from 13 km to 20 km. The heat flow map values range from 69 to 109 mW/m2, with an average of about 80 mW/m2. The calculated heat flow values in the assigned areas (A, B, C, and D) of the study area are considered to have high heat flow values, reaching 109 mW/m2. On the other hand, the heat flow values in the other parts range from 70 to 85 mW/m2. Since heat flow plays an essential role in the maturation of organic matter, it is recommended that hydrocarbon accumulations be located in places with high heat flow values, while deep drilling of hydrocarbon wells is recommended in places with low to moderate heat flow values.

掺杂对巨磁电阻钙钛矿La_(1-x)A_x(MnB)O_3 Curie温度的影响

测定了La1 -xAx(MnB)O3(A为二价元素 )型巨磁电阻钙钛矿化合物在不同组成时的Curie温度。钙钛矿锰氧化物La1 -xAxMnByO3的A位离子掺杂引起的晶格畸变可以用晶格能来表示 ,晶格能的大小能很好解释A位离子掺杂引起的Curie温度变化 ;B位离子掺杂引起的晶格畸变可用极化力来表示 ,极化力的大小很好解释了B位离子掺杂引起的Curie温度变化。钙钛矿锰氧化物的A ,B位离子同时掺杂引起晶格畸变 ,可以用晶格能和极化力的综合判断系数 (晶格能 /极化力 )来表示 ,它能很好解释A和B位离子同时改变引起的Curie温度变化 ,理论与实验结果一致。

双相软磁合金晶间非晶相Curie温度的增强效应

控制退火处理工艺使Fe73.5Cu1Nb3Si13.5B9非晶合金发生纳米晶化,获得不同晶粒尺度和晶相体积分数的非晶纳米晶双相组织状态.基于铁磁学严格Heisenberg自旋交换模型,构造适合非晶纳米晶双相结构要求的双相自旋团聚点阵.采用MonteCarlo模拟方法对上述双相自旋交换耦合点阵进行数值模拟计算.实验测定了经不同退火处理后双相Fe73.5Cu1Nb3Si13.5B9合金的纳米晶粒大小、纳米晶相所占体积分数以及晶间非晶相厚度对晶间非晶相Curie温度的影响.发现晶间非晶相Curie温度与其厚度的倒数成线性关系.模拟计算与实验测量结果相符.

^(123)I-MIBG SPECT/CT断层显像在儿童神经母细胞瘤Curie评分中的价值分析

目的探讨123碘-间碘苄胍(^(123)I-metaiodobenzylguanidine,^(123)I-MIBG)平面显像和单光子发射型计算机断层成像(single-photon emission computed tomography,SPECT/CT)在儿童神经母细胞瘤Curie评分中的价值。方法分析211例神经母细胞瘤患儿的^(123)I-MIBG平面显像和SPECT/CT断层显像的图像,所有患儿均属于3期或4期的高危患者。收集^(123)I-MIBG平面显像和SPECT/CT断层显像的Curie评分,以病理结果、其他相关的影像学检查及临床随访为神经母细胞瘤病灶诊断的依据,分别比较两种显像方式的差异性,以及它们与金标准的一致性和诊断准确率。结果在211例患儿中,48.82%(103/211)的患儿基于^(123)I-MIBG平面显像和SPECT/CT断层显像的Curie评分是一致的。51.18%(108/211)的患儿^(123)I-MIBG平面显像和SPECT/CT断层显像差异有统计学意义。123 I-MIBG平面显像的Curie评分为0(0,1)分,SPECT/CT断层显像的Curie评分为0(0,2)分,两种显像方式的Curie评分差异有统计学意义(Z=-3.46,P<0.001)。依据Curie评分的结果,将患者分为高分组(≥2)和低分组(<2),两种显像方式的分组差异有统计学意义(P=0.001)。^(123)I-MIBG平面显像和SPECT/CT断层显像的诊断正确率分别为51.66%和93.84%,两种显像方法的诊断准确率差异有统计学意义(P<0.001);它们与金标准的诊断一致性分别为0.44(0.34~0.54)和0.90(0.85~0.96),相较于^(123)I-MIBG平面显像,SPECT/CT断层显像具有极好的一致性。结论与^(123)I-MIBG平面显像相比,SPECT/CT断层显像具有更高的诊断准确率及诊断一致性;基于^(123)I-MIBG SPECT/CT断层显像的Curie评分,对患儿全身肿瘤情况的半定量评估具有非常重要的意义。

高Curie温度(1-2x)PbNb_2O_(6)-xSrTiO_(3)-xTiO_2压电陶瓷

采用传统电子陶瓷的制备方法制备了(1-2x)PbNb2O6-xSrTiO3-xTiO2(x=0.005～0.025)高Curie温度(θC)压电陶瓷。X射线衍射分析表明:所有样品在1250℃保温2h烧结均形成铁电性的斜方钨青铜型结构(tungsten bronze structure,TB)。相对介电常数-温度(εr-θ)曲线表明:该体系具有高的θC(500～560℃)。测试了不同掺杂量对陶瓷介电和压电性能的影响,发现材料的θC、压电常数(d33)和机电耦合系数(kp)随着x值的增加先增加后降低。当x=0.02时,陶瓷的d33达到最大值,为83pC/N,θC为550℃,kp达33.4%,材料的介电常数ε3θ3/ε0为217,为组成的最优配方。

Piezoelectric properties of low loss and high Curie temperature (Bi, La)FeO_3-Pb(Ti, Mn)O_3 ceramics with Mn doping

Piezoelectric ceramics of 0.6(Bi0.9La0.1)FeO3-0.4Pb(Ti1-xMnx)O3 (BLF-PTM) for x=0, 0.01, 0.02, and 0.03 were prepared by sol-gel process combined with a solid-state reaction method. The tan? for BLF-PTM of x=0.01 is just 0.006 at 1 kHz, drastically decreasing by using Mn dopants. The TC increases to 490 ℃ for BLF-PTM of x=0.02. Furthermore, Mn modification effectively enhances the poling state and the piezoelectric properties of BLF-PTM. The kp, Qm, d33, and g33 of 0.34, 403, and 124 pC1·N-1 and 37×10-3 Vm·N-1 are achieved for BLF-PTM of x=0.01. The results indicate that Mn modified BLF-PTM is a competitive high power and high temperature piezoelectric material with excellent piezoelectric properties.

Magnetic entropy change and magnetic properties of LaFe_(11.5)Si_(1.5) after controlling the Curie temperature by partial substitution of Mn and hydrogenation

Magnetic properties and magnetic entropy changes of La（Fe_（1-x）Mn_x）_（11.5）Si_（1.5）H_y compounds are investigated. Their Curie temperatures are adjusted to room temperature by partial Mn substitution for Fe and hydrogen absorption in 1-atm（1 atm = 1.01325×10~5Pa） hydrogen gas. Under a field change from 0 T to 2 T, the maximum magnetic entropy change for La（Fe_（0.99）Mn_（0.01））_（11.5）Si_（1.5）H_（1.61）is-11.5 J/kg. The suitable Curie temperature and large value of ？S_m make it an attractive potential candidate for the room temperature magnetic refrigeration application.

Curie and Pauli Spins in Lithium Intercalated MCMB

The ESR signal of lithium intercalated MCMB can be well simulated by combination of a Lorentz curve and a Gauss curve. The ESR intensity of the Lorentz component is essentially independent of temperature while the Gauss component shows a linear change with the reciprocal of temperature, indicative of Pauli spin and Curie spin, respectively. The former is probably associated with the ordered (graphitized) structures while the latter with the disordered structures in the sample.

ANOMALOUS EFFECT OF PRESSURE ON THE CURIE TEMPERATURE IN MECHANICALLY ALLOYED Fe-Ni INVAR

Measurements of magnetic susceptibility in mechanically alloyed Fe-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of decrease in the Curie temperature for 700℃ annealed specimen was larger than that annealed at 1000℃. This result can be explained by considering the fact that the width of the concentration fluctuation becomes larger in the specimen annealed at lower temperature.

Depth to the bottom of magnetic layer in South America and its relationship to Curie isotherm,Moho depth and seismicity behavior

We have estimated the DBML（depth to the bottom of the magnetic layer） in South America from the inversion of magnetic anomaly data extracted from the EMAG2 grid. The results show that the DBML values, interpreted as the Curie isotherm, vary between -10 and -60 km. The deepest values（〉-45） are mainly observed forming two anomalous zones in the central part of the Andes Cordillera. To the east of the Andes, in most of the stable cratonic area of South America, intermediate values（between -25 and-45 km） are predominant. The shallowest values（〈-25 km） are present in northwestern corner of South America, southern Patagonia, and in a few sectors to the east of the Andes Cordillera. Based on these results, we estimated the heat flow variations along the study area and found a very good correlation with the DBML. Also striking is the observation that the thermal anomalies of low heat flow are closely related to segments of flat subduction, where the presence of a cold and thick subducting oceanic slab beneath the continent, with a virtual absence of hot mantle wedge, leads to a decrease in the heat transfer from the deeper parts of the system.After comparing our results with the Moho depths reported by other authors, we have found that the Curie isotherm is deeper than Moho in most of the South American Platform（northward to -20°S）, which is located in the stable cratonic area at the east of the Andes. This is evidence that the lithospheric mantle here is magnetic and contributes to the long wavelength magnetic signal. Also, our results support the hypothesis that the Curie isotherm may be acting as a boundary above which most of the crustal seismicity is concentrated. Below this boundary the occurrence of seismic events decreases dramatically.

MAGNETIC MOMENT,CURIE TEMPERATURE AND SPIN WAVE EXCITATION FOR AMORPHOUS Fe_(90-x)Si_xZr_(10) ALLOYS

The magnetization curves at 1.5 K and thermomagnetic curves for amorphous Fe_(90-x)Si_xZr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique have been measured with an extracting sample magnetometer.It is obtained that the average magnetic moment,,per magnetic atom and Curie temperature,T_c,in the amorphous FeSiZr alloys increase with increasing Si content.The and T_c are found to be quite small,compared with amorphous FeSiB alloys.This unusual behavior is suggested to be due to the presence of the Fe—Fe antiferromagnetic interactions.The temperature dependence of magnetization at lower temperature is in accordance with Bloch's T^(3/2) law.Calculation shows that the spin wave stiffness constant,D,increases with increasing Si content from 0.37 meV·nm^2 for x=0 to 0.538 meV·nm^2 for x=10.The values of<r^2>indicate that the range of the exchange interaction is roughly the mean atomic distance of nearest neighbours.

Influence of Non-Magnetic Substitutional Atoms on Spontaneous Moment and Curie Temperature of Ce_2Co_(17) Compounds

The structure and magnetic properties of Ce 2Co 17-xM x(M=Ga,Al and Si) compounds for M concentrations up to x=5 were studied by means of X-ray diffraction and magnetic measurements. The experimental results show that the Curie temperatures and Co spontaneous magnetization decrease significantly with increasing the addition of non-magnetic substitutional atoms, and that Si which has a minimum solid solubility in Ce 2Co 17 causes a largest reduction of Curie temperature, spontaneous magnetization and moment per Co atom compared with Ga and Al.

Curie Temperature of the Intergranular Amorphous Phase in Nanocrystalline Fe_(89)Zr_7B_4 Alloy

The FeZrB amorphous alloys for simulating the intergranular amorphous phase in the nanocrystalline Fe 89 Zr 7B 4 soft magnetic materials were obtained by mechanical alloying of a mixture of elemental Fe, Zr and B powders for 25 h. It is shown that the Curie temperature of the simulated intergranular phase alloy is much lower than that of the intergranular phase with the same chemical composition in the nanocrystalline Fe 89 Zr 7B 4 alloy. The possible mechanism is mainly due to the strong ferromagnetic exchange force among the nanocrystalline α Fe grains.

Investigation of Curie Point Depth in Sulu Ultrahigh-Pressure Metamorphic Belt,Eastern China

The Curie point depth of continental crust can reflect the regional tectonic pattern and geothermal structures. Analysis of magnetism is an efficient way to obtain the Curie point depth on a regional scale. This study systematically investigated the Curie point depth of Sulu （苏鲁） ultrahigh pressure （UHP） metamorphic belt （33°40＇N to 36°20＇N and 118°E to 120°E, ca. 60 000 km^2）, eastern China using aeromagnetic data. The results show that the Curie point depth of the Sulu region varies from 18.5 to 27 km. The shallowest Curie point depth （ca. 18.5 km） is located in Subei （苏北） subsidence, where the estimated temperature gradient value is about 31.35℃/km, which is comparable with the measured value of 30 ℃/km. In addition, a two-dimensional numerical solution of the heat conduction was used to calculate the temperature field to a depth of 30 km along the profile from Tancheng （郯城） to Lianshui （涟水） with a length of 139 km. The steady state model solved using the finite element method shows that the temperature around the Curie point depth is about 585.36 ℃, which is close to the Curie temperature （580℃） of magnetite at atmospheric pressure. These results provide new insights into the tectonic and continuous thermal structures of the Sulu UHP metamorphic belt.

Curie Temperature of Amorphous Fe-Si-B and Fe-W-Si-B Alloys

オhe effects of composition, annealing temperature and time, annealing heating rate on the Curie temperature of amorphous FeSiB and FeWSiB alloys were studied. The results indicate that the Curie temperature of these alloys increases with the increase of the metalloid content when it is <25 at%, then decreases with the further increase of the metalloid content. For amorphous FeSiB and FeWSiB alloys with the low metalloid content, the Curie temperature increases with the annealing temperature and the annealing time. However, for the amorphous FeWSiB alloys with the high metalloid content, the Curie temperature increases at low annealing temperature and with short annealing time, and decreases at high annealing temperature and with long annealing time. The heating rate in measuring Curie temperature also influences the Curie temperature of the alloys. The Curie temperature is higher at lower heating rates.

High Ferroelectricities and High Curie Temperature of BiInO3PbTiO3Thin Films Deposited by RF Magnetron Sputtering Method

Properties of ferroelectric xBiInO3-（1-x）PbTiO3（xBI-（1-x）PT） thin films deposited on（101） SrRuO3/（200）Pt/（200） MgO substrates by rf magnetron sputtering method and effects of deposition conditions are investigated.The structures of the xBI-（1-x）PT films are characterized by x-ray diffraction and scanning electron microscopy.The results indicate that the thin films are grown with mainly（001） orientation. The chemical compositions of the films are analyzed by scanning electron probe and the results indicate that the loss phenomena of Pb and Bi elements depend on the pressure and temperature during the sputtering process.The sputtering parameters including target composition, substrate temperature, and gas pressure are adjusted to obtain optimum sputtering conditions. To decrease leakage currents,2 mol% La2 O3 is doped in the targets. The P-E hysteresis loops show that the optimized xBI-（1-x）PT（x = 0.24） film has high ferroelectricities with remnant polarization2 Pr = 80μC/cm2 and coercive electric field 2 EC = 300 kV/cm. The Curie temperature is about 640℃. The results show that the films have optimum performance and will have wide applications.