Improved Resolution and Cost Performance of Low-Cost MEMS Seismic Sensor through Parallel Acquisition.

In earthquake monitoring, an important aspect of the operational effect of earthquake intensity rapid reporting and earthquake early warning networks depends on the density and performance of the deployed seismic sensors. To improve the resolution of seismic sensors as much as possible while keeping costs low, in this article the use of multiple low-cost and low-resolution digital MEMS accelerometers is proposed to increase the resolution through the correlation average method. In addition, a cost-effective MEMS seismic sensor is developed. With ARM and Linux embedded computer technology, this instrument can cyclically store the continuous collected data on a built-in large-capacity SD card for approximately 12 months. With its real-time seismic data processing algorithm, this instrument is able to automatically identify seismic events and calculate ground motion parameters. Moreover, the instrument is easy to install in a variety of ground or building conditions. The results show that the RMS noise of the instrument is reduced from 0.096 cm/s2 with a single MEMS accelerometer to 0.034 cm/s2 in a bandwidth of 0.1-20 Hz by using the correlation average method of eight low-cost MEMS accelerometers. The dynamic range reaches more than 90 dB, the amplitude-frequency response of its input and output within -3 dB is DC -80 Hz, and the linearity is better than 0.47%. In the records from our instrument, earthquakes with magnitudes between M2.2 and M5.1 and distances from the epicenter shorter than 200 km have a relatively high SNR, and are more visible than they were prior to the joint averaging.

Ventriculoperitoneal shunts in non-HIV cryptococcal meningitis.

BACKGROUND: Persistent and uncontrollable intracranial hypertension (ICH) and difficulty in reducing Cryptococcus count are severe problems in cryptococcal meningitis (CM) patients. The therapeutic effects of ventriculoperitoneal shunts (VPS) in non-HIV CM patients are not fully known, and the procedure is somewhat unusual. Here, our study offers a review to investigate the role of VPS in non-HIV CM. METHODS: We retrospectively collected data on 23 non-HIV CM patients with and without ventriculomegaly from 2010 to 2016. Their demographic data, clinical manifestations, cerebrospinal fluid (CSF) features and outcomes were analysed. RESULTS: We found that non-HIV CM patients without ventriculomegaly were older, had earlier treatment times and had shorter symptom durations than CM patients with ventriculomegaly. In both groups, headache, vomiting, fever and loss of vision were the most common clinical features. CSF pressure and Cryptococcus count were significantly decreased after operation. VPS could provide sustained relief from ICH symptoms such as headache. 13% of patients had poor outcomes because of serious underlying disease, while 87% of patients had good outcomes. CONCLUSIONS: The use of a VPS is helpful in decreasing ICH and fungal overload in non-HIV CM patients, and VPS should be performed before CM patients present with symptoms of severe neurological deficit.

A novel three-dimensional zinc(II) coordination polymer based on 3,3'-{[1,3-phenylenebis(methylene)]bis(oxy)}dibenzoic acid and 1,4-bis(pyridin-4-yl)benzene: synthesis, crystal structure and photocatalytic properties.

A novel three-dimensional (3D) ZnII coordination polymer, namely, poly[[[1,4-bis(pyridin-4-yl)benzene](µ3-3,3'-{[1,3-phenylenebis(methylene)]bis(oxy)}dibenzoato)zinc(II)] 1,4-bis(pyridin-4-yl)benzene], {[Zn(C22H16O6)(C16H12N2)]·C16H12N2}n or {[Zn(PMBD)(DPB)]·DPB}n, 1, where H2PMBD is 3,3'-{[1,3-phenylenebis(methylene)]bis(oxy)}dibenzoic acid and DPB is 1,4-bis(pyridin-4-yl)benzene, has been synthesized by self-assembly using zinc nitrate, a semi-rigid dicarboxylic acid and a nitrogen-containing ligand. The single-crystal X-ray structure determination indicates that 1 possesses an intriguing 3D architecture with a 4-connected uninodal cds topology, which is constructed from dinuclear {Zn2} clusters and V-shaped PMBD2- linkers. Compound 1 exhibits excellent photocatalytic activity on the degradation of the organic dyes Rhodamine B (RhB), Rhodamine 6G (Rh6G) and Methyl Red (MR).

Postinfectious inflammatory response syndrome in HIV-uninfected and nontransplant men after cryptococcal meningitis.

Aim: The aim of our study was to describe the characteristics of postinfectious inflammatory response syndrome (PIIRS) in HIV-uninfected and nontransplant men after cryptococcal meningitis (CM). Patients & methods: A case-control study was designed to compare HIV-uninfected and nontransplant male CM patients with and without PIIRS. Results: CM-PIIRS patients had increased rates of hearing loss, V-P shunt placement, amphotericin B treatment, higher cerebrospinal fluid pressures and Cryptococcus counts in the first CM episode. CM-PIIRS episode was characterized by higher frequencies of headache and fever, higher C-reactive protein, erythrocyte sedimentation rate, cerebrospinal fluid white blood cell (WBC) counts and modified Rankin Score. Brain MRI scans revealed the high signal lesions on axial flair imaging. Receipt of corticosteroid therapy was associated with lower rates of fever and better modified Rankin Score scores at 1 month after treatment. Conclusion: CM-PIIRS episode differs to the initial presentation, may help to identify which patients are at risk to develop PIIRS. Steroids therapy could be beneficial.

Two Lanthanide Metal⁻Organic Frameworks Based on Semi-Rigid T-Shaped Tricarboxylate Ligand: Syntheses, Structures, and Properties.

By using a semi-rigid tripodal ligand 5-(4-carboxybenzyloxy)isophthalic acid (H3L) and lanthanide metal ions (Nd3+, Tb3+), two novel lanthanide metal-organic frameworks, namely, {[Nd2L2(DMF)4] DMF}n (1), and {TbL(DMF)(H2O)}n (2), were synthesized under mild solvothermal conditions and structurally characterized by X-ray single crystal diffraction. Compounds 1 and 2 are isostructural, in which L3- ligands linked dinuclear lanthanide metal-carboxylate units to form non-interpenetrated 3D network with (3,6)-connected topology. Luminescent investigations reveal that compound 1 displays the near-infrared emission at room temperature, and compound 2 can be employed as selective probe for Cr2O72- anion in aqueous solution based on luminescence quenching. Moreover, compound 2 exhibits catalytic activity for cyclo-addition of CO2 and epoxides under relatively mild conditions.

Comprehensive analysis of patients with neuromyelitis optica spectrum disorder (NMOSD) combined with chronic hepatitis B (CHB) infection and seropositive for anti-aquaporin-4 antibody.

Previous research indicated the association between hepatitis B virus (HBV) infection/vaccination and the onset of demyelinating diseases. However, most of these studies were single case reports, and comprehensive data are still scarce. Here we present a comprehensive analysis of 10 patients with neuromyelitis optica spectrum disorder (NMOSD) combined with chronic hepatitis B (CHB) infection and seropositive for anti-aquaporin-4 antibody (AQP4-Ab). Demographic, clinical, laboratory, neuroimaging, outcome, and follow-up data of the 10 patients were retrospectively analyzed. The median age at the onset of NMOSD was 35 years (range 25-43). Nine patients were female (90%). All patients were positive for HBsAg and had been diagnosed with CHB earlier than with NMOSD. One patient had an autoimmune disease. All patients had normal thyroid function. Paresthesia and visual impairment were the most common clinical symptoms. The cerebrospinal fluid (CSF) parameters (protein and glucose) were normal in 10 cases, whereas slightly higher CSF white blood cell count was detected in 3 patients. The brain and spinal cord magnetic resonance imaging findings were abnormal in 8 patients. All patients were treated with hormone and immunosuppressive therapy, and anti-HBV agents. Patients with detectable serum HBV DNA were more prone to liver damage after receiving high doses of corticosteroids. In 8 patients, the symptoms improved before they were discharged. Two patients with optic neuritis (ON) maintained the symptoms. A month later, 1/8 patient had recurrence of symptoms, and one ON patient progressed to NMO. Overall, the characteristics of NMOSD patients with CHB and seropositive for AQP4-Ab are usually nonspecific. Abnormal liver function test results in NMOSD patients should be a warning of possible CHB infection, and the treatment should be modified accordingly.