Idiopathic basal ganglia calcification associated with cerebral micro-infarcts: a case report

Abstract Background Idiopathic basal ganglia calcification (IBGC) is a rare neurodegenerative disorder characterized by symmetric intracranial calcium deposition. We report a patient with IBGC associated with cerebral infarction due to impairment of cerebrovascular reactivity based on single-photon emission computed tomography (SPECT) with acetazolamide challenge. Case presentation A 66-year-old male presented with right conjugate deviation, right hemiparesis and total aphasia due to a convulsive seizure. Brain computed tomography showed symmetric calcifications in the bilateral basal ganglia, thalamus, cerebellar dentate nuclei, which were consistent with IBGC. Diffusion-weighted brain magnetic resonance imaging showed multiple small infarctions in the bilateral cerebral subcortical area. In the search for the cause of cerebral infarction, SPECT with acetazolamide challenge revealed heterogeneous impairment of cerebrovascular reactivity in the whole brain, despite the absence of evidence for steno-occlusive changes in proximal arteries. Conclusion Cerebrovascular insufficiency due to the lack of elasticity caused by microvascular calcification might have been one of the pathophysiological features of IBGC in this case. Thus, vascular calcification may cause cerebrovascular disturbance and could lead to ischemic stroke in patients with IBGC

Relationship between attributes of individual workers and concentration at work

Working environments are becoming far more diverse. For example, Activity-Based Working (ABW), a new style of working where workers choose their own work environment, is now attracting attention. An office that introduces ABW is comprised of various spaces, including open plan workspaces, corresponding to the ways of working. However, such an office may result in distraction. Therefore, it is necessary to identify the environmental factors that affect individual workers’ concentration at work. This study aimed to ascertain the relationship between individual workers’ attributes, such as the Big Five personality traits, personal control, and age, and the factors that distract them from their work. A questionnaire-based field survey was conducted at an office that partially adopted ABW to investigate the relationship between selection of seats and concentration at work. The results revealed different tendencies among workers for the type of work environment needed to concentrate according to their individual attributes. Additionally, it was suggested that the changing of seats lead to improved concentration at work, thus increasing productivity

Near-infrared spectroscopy of low-transmittance samples by a high-power time-stretch spectrometer using an arrayed waveguide grating (AWG)

Abstract Although time-stretch spectroscopy is an emerging ultrafast spectroscopic technique, the applications in industrial fields have been limited due to the low output power caused by undesirable nonlinear effects occurred in a long optical fiber used for pulse chirping. Here, we developed a high-power time-stretch near infrared (NIR) spectrometer utilizing arrayed waveguide gratings (AWGs). The combination of AWGs and short optical fibers allowed large amounts of chromatic dispersion to be applied to broadband supercontinuum pulses without the power limitation imposed by employing the long optical fiber. With the proposed configuration, we achieved chirped pulses with the output power of 60 mW in the 900–1300 nm wavelength region, which is about 10 times higher than conventional time-stretch spectrometers using long optical fibers. With the developed spectrometer, the NIR absorption spectra of a standard material and liquid samples were observed with high accuracy and precision within sub-millisecond measurement time even with four orders of magnitude optical attenuation by a neutral density filter. We also confirmed the quantitative spectral analysis capability of the developed spectrometer for highly scattering samples of an oil emulsion. The qualitative comparison of the measurement precision between the developed spectrometer and the previous time-stretch spectrometer was also conducted