Publications by authors named "Heyuan Jia"

Miniaturized mass spectrometers offer significant potential for in situ analysis due to their high specificity and portability. In traditional data-dependent acquisition (DDA) mode, precursor ions for tandem analysis are selected based on the full-scan mass spectrum. However, in situ applications often require the direct analysis of complex samples without extensive sample pretreatment, making them susceptible to chemical noise that can result in false negatives.

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Intraventricular tumors frequently provoke alterations in ventricular morphology. This study aims to quantificational assess perioperative dynamic fluctuations in the cerebrospinal fluid (CSF) volume within the lateral ventricles of patients harboring lateral ventricular tumors. A retrospective review encompassing 90 patients who underwent surgical intervention for lateral ventricular tumors at our institution was undertaken.

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Objective: Despite pituitary neuroendocrine tumor (PitNET) being extra-axial tumors without direct damage to brain tissue, patients with PitNET exhibit neuropsychological impairments. However, it remains unclear whether there are neuropsychological differences between PitNET and intra-axial tumors that directly destroy the brain parenchyma. This prospective study aims to clarify this distinction to inform decision-making for intracranial tumors of diverse origins.

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One of the main challenges of analyzing intact proteins on an ion trap mass spectrometer is the mass range limitation, especially for miniature mass spectrometers. In this study, a high-field frequency scanning ion trap miniature mass spectrometer, namely the high-field "Brick" mass spectrometer, was developed to analyze intact proteins. A high-voltage broadband radio frequency (rf) amplifier was designed with a maximum output of 900 V over a frequency range of 130-700 kHz.

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Efficient transmission of low-mass ions in a rough vacuum pressure region has always been a challenging issue in mass spectrometry (MS). In this study, a novel ion guide, namely, field-gradient-focusing ion guide (FGF-IG), was proposed to improve the transfer efficiency of ions, especially low-mass ions in a rough vacuum region. The FGF-IG has 12 electrodes whose surfaces gradually narrowed and tilted inward, and its electric field gradually varies from dodecapole (or multipole) to quadrupole along the ion transfer route.

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Purpose: It remains unclear as to whether patients with brainstem tumor experience complex neuropsychiatric problems. In this cohort study, we specifically investigated behavioral, emotional and cognitive symptoms in pediatric patients with brainstem glioma and healthy individuals.

Methods: A total of 146 patients with pediatric brainstem tumors (aged 4-18 years old) and 46 age-matched healthy children were recruited to assess their behaviors and emotions examined by the Child Behavior Checklist.

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With increasingly improved analytical performances, miniature mass spectrometers are expandingly applied in more application scenarios. The capability of high throughput analysis of multi-targets is a crucial function of a miniature mass spectrometer, especially for in-situ applications. As a powerful method for target screening, multiple reaction monitoring (MRM) was conventionally realized on triple quadrupole (QQQ) mass spectrometers.

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