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Mass resolution of Foureir transform mass spectrometer (FTMS) highly depends on the acquisition time of image charge/current signal. In order to achieve higher resolution with a shorter transient time, apart from increasing the field strength of the analyzer, the high order harmonics in the image charge signal may also be exploited. The image charge or current signal obtained from the planar electrostatic ion trap has a non-sinusoidal waveform which contains many high-order harmonic components. However, presence of high harmonics increases the complexity of spectral analysis, such as identification of a peak for its correct harmonic order, and avoiding quantitation error due to the peak overlapping from different harmonic groups. A new quantitative algorithm consists of a scoring-based peak classification and the least square fitting (SC-LSF), which has been developed to convert image charge or current signal to mass spectrum. The scoring process will go through all the peaks identified above the noise background, for assumptions that the peak belongs to a certain harmonic order. The score will go up when a relevant lower harmonic peak is confirmed. The harmonic order which achieves the highest score, is assigned to the peak so its fundamental frequency can be determined. Through the SC tests, the candidates of all fundamental frequencies are found for all possible m/z of ions. The basis signals for all possible m/z are constructed using the identified fundamental frequencies and are brought to the LSF to determine the intensities of each species. The SC-LSF algorithm was tested using simulated signal from a mixture of 48 different m/z ions. Different levels of artificial noise were added to the signal to challenge the algorithm. The results show a wide range of mass and ion numbers in the sample mixture can be accurately returned through the SC-LSF algorithm even if the transient signal is under high noise condition. LSF in frequency domain is more efficient than in time domain because a subset of frequency points may be selected, so the amount of calculation is massively reduced. In addition, the test proves that good quantitation can be achieved only when LSF is carried out using data in complex number, while fitting with magnitude data results in large errors for ions in the closed mass group. This is because those closed mass peaks are overlapping at certain low-order harmonics and the amplitudes of a FFT spectrum are not addable, thus leading to the fitting errors.

Objective A retrospective analysis of the clinical and pathological features of an anaplastic large cell lymphoma (ALCL) with cavernous sinus syndrome as its first symptom. Methods and Results A 35-year-old woman had head and facial pain for a month, diplopia for 7 d, right eyelid drooped for 4 d. Head MRI showed abnormal signals in right cavernous sinus, and pituitary adenoma or carvernous sinus syndrome were considered. Partial tumor resection was performed after hormone therapy was failed. Histological manifestations revealed that the tumor cells were diffuse and heterogeneous with abundant and pink stained cytoplasm, round, oval, irregular or kidney-shaped nuclei. Immunohistochemical staining showed that CD30 and CD56 were positive on the membrane, and epithelial membrane antigen (EMA) was positive on membrane and cytoplasm, and anaplastic lymphoma kinase (ALK) was negative. Ki-67 labeling index was 80%. Unfortunately, this patient died 3 weeks later after the operation, because of severe illness and intolerance to radiotherapy and chemotherapy. Conclusions The diagnosis of ALCL should be considered when cavernous sinus syndrome as the clinical symptom, and pathological examination should be performed if necessary. It should be differentiated from some tumors, such as undifferentiated non-keratinizing nasopharyngeal carcinoma, germinoma, plasmablastic lymphoma, malignant melanoma and Hodgkin's lymphoma (HL). DOI:10.3969/j.issn.1672-6731.2019.09.014

Objective To report our experiences of direct cortical stimulation in surgery of gliomas located in eloquent areas. Methods Clinical data of 157 patients with gliomas underwent awake craniotomy with the direct electrical stimulation for functional mapping of the eloquent areas were analysed retrospectively. Results Negative cortical stimulation was found in 4 patients, and positive cortical stimulation was achieved in 153 patients (97.45% ). Four hundred and ninty ⁃ six cortical sites in 139 patients were detected for motor response by direct electrical stimulation, 70 sites in 21 patients for sensory, 112 sites in 91 patients for language (such as counting and naming). The positive areas of counting disturbance were mainly seen at the lower part of left precentral gyri operculum of left inferior frontal gyri, triangular part of left inferior frontal gyri, posterior part of left middle frontal gyri, and posterior part of left superior frontal gyri. Postoperative MRI showed 92 patients (58.60%) achieved total resection, 55 cases (35.03%) subtotal and 10 cases (6.37%) partial. One hundred and ten patients (70.06%) were diagnosed as having low grade glimas, including 71 cases of astrocytoma, 26 cases of oligodendroglioma, and 13 cases of mixed astro ⁃ oligodendroglioma, 47 patients (29.94% ) were high grade gliomas, including 19 cases of glioblastoma, 15 cases of anaplastic astrocytoma, and 13 cases of anaplastic oligodendroglioma. After operation 53 patients (33.76% ) occurred transient postoperative paralysis, 39 patients (24.84% ) transient language disturbance and 4 patients (2.55%) permanent neurological deficits. Conclusion Intraoperative direct electrical stimulation is a reliable, precise and safety method for functional mapping of the eloquent areas. This technique allows us to achieve 'maximal safety resection' in glioma surgery． DOI：10.3969/j.issn.1672⁃6731.2012.06.011

With a view to investigating the effect of wheat sprouting degree on the cooking quality, textural characteristics and sensory evaluation of dried whole wheat noodles, whole wheat flours with different degrees of wheat sprouting (bulging, revealing, sprout length equal to 1/4, 1/2, 3/4 the grain length, and the grain length) were used to prepare dried whole wheat noodles. The results showed that the surface brightness of whole wheat noodles first increased and then decreased with the increase in wheat sprouting degree. The moisture absorption rate of dry matter reached the maximum when the sprout length was 1/2 the grain length, and the dry matter loss rate reached the minimum at the revealing stage. The viscosity and adhesion capacity of whole wheat noodles reached the minimum when the sprout length was 1/2 the grain length, and the hardness and shear work reached the maximum when the sprout length was 1/4 the grain length, and the breaking strength, tensile strength, elasticity and sensory score were the maximum when the sprout length was 1/2 the grain length. Overall, the eating quality of dried whole wheat noodles prepared from whole wheat flour at the stage of wheat revealing to sprout length equal to 1/2 the grain length was the best, and the overall eating quality of noodles prepared from sprouted whole wheat flour was improved compared with that of the control prepared from un-sprouted whole wheat flour.