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Biosensors have been widely used in various fields such as food industry, environmental testing and medical testing for their high sensitivity. However, current fabrication methods of biosensors, such as screen printing, micro fabrication and 3D printing suffer from complex procedures, requirement of cleanroom facility and limited fabrication materials, which significantly restrict the development and utilization of biosensors. Here, we propose a movable type bioelectronics printing method for the fabrication of biosensors by directly transferring bioelectronic materials onto various substrates using pre-fabricated molds. This simple, low-cost, yet robust method facilitates on-demand printing of master molds of partial or complete circuits on both rigid or flexible substrates. With this method, bioactive materials such as enzymes can be directly transferred onto substrates together with other electronic components, without complex modification after electrode fabrication using conventional methods. For demonstration, a dual-channel flexible electrochemical biosensor was fabricated by the movable type bioelectronics printing method for continuous monitoring of glucose and lactate. The movable type bioelectronics printing technology holds advantages of repeatability, flexibility and low cost for fabrication of biosensors on rigid and flexible substrates, as well as direct transfer printing of bioactive materials, which greatly promotes small-scale production of biosensors.

Thrombosis is the formation of a blood clot inside a blood vessel and there are two kinds of thrombosis: venous thrombosis and arterial thrombosis. It is a fatal cardiovascular disease and has caused a lot of pain to human body. Through this passage, we analyze the potential mechanism of thrombosis from non-biomechanics and biomechanics respects. Furthermore, the article concludes its current diagnosis and treatment and points out their responding advantages and disadvantages, after which I propose a possible solution for both diagnosing and curing thrombosis with photoacoustic imaging technology which would be convenient and highly efficient to diagnose and cure thrombosis.

We established a photoacoustic imaging (PAI) system that can provide variable gain at different depths. The PAI system consists of a pulsed laser with an optical parametric oscillator working at a 728[Formula: see text]nm wavelength and an imaging-acquisition-and-processing unit with an ultrasound transducer. A voltage-controlled attenuator was used to realize variable gain at different depths when acquiring PAI signals. The proof-of-concept imaging results for variable gain at different depths were achieved using specific phantoms. Both resolution and optical contrast obtained through the results of variable gain for a targeted depth range are better than those of constant gain for all depths. To further testify the function, we imaged the sagittal section of the body of in vivo nude mice. In addition, we imaged an absorption sample embedded in a chicken breast tissue, reaching a maximum imaging depth of [Formula: see text]4.6[Formula: see text]cm. The results obtained using the proposed method showed better resolution and contrast than when using 50[Formula: see text]dB gain for all depths. The depth range resolution was [Formula: see text]1[Formula: see text]mm, and the maximum imaging depth of our system reached [Formula: see text]4.6[Formula: see text]cm. Furthermore, blood vessels can be revealed and targeted depth range can be selected in nude mice imaging.

Background: Infrared laser stimulation has been proposed as an innovative method to elicit an auditory nerve response. Most studies have focused on using long-wavelength infrared ([Formula: see text][Formula: see text]nm) pulsed lasers with high water absorption coefficients. This paper sought to assess whether a short-wavelength laser (465[Formula: see text]nm) with an absorption coefficient as low as 10[Formula: see text][Formula: see text]cm[Formula: see text] would activate the auditory nerve and studied its potential mechanism. Method: Optical compound action potentials (OCAPs) were recorded when synchronous trigger laser pulses stimulate the cochlea before and after deafening, varying the pulse durations (from 800[Formula: see text][Formula: see text]s to 3600[Formula: see text][Formula: see text]s) and the amount of radiant energy (from 18.05[Formula: see text]mJ/cm2 to 107.91[Formula: see text]mJ/cm2). A thermal infrared imager was applied to monitor the temperature change of the guinea pig cochlea. Results: The results showed that pulsed laser stimulation at 465[Formula: see text]nm could invoke OCAPs and had a similar waveform compared to the acoustical compound action potentials. The amplitude of OCAPs had a positive correlation with the increasing laser peak power, while the latency of OCAPs showed a negative correlation. The imager data showed that the temperature in the cochlea rose quickly by about 0.3[Formula: see text]C right after stimulating the cochlea and decreased quickly back to the initial temperature as the stimulation ended. Conclusions: This paper demonstrates that 465-nm laser stimulation can successfully induce OCAPs outside the cochlea, and that the amplitude and latency of the invoked OCAPs are highly affected by laser peak power. This paper proposes that a photothermal effect might be the main mechanism for the auditory nerve response induced by short-wavelength laser stimulation.

Lack of standard metadata and file formats make it challenging to archive and distribute remote sensing data. Although the Common Data Model (CDM) developed by Unidata has the potential of providing easy access to data stored in a variety of file formats, it would still be necessary to maintain each I/O library ever used to create a data product. Moreover, due to the nature of these data structures, I/O libraries are often complicated and expensive to maintain. As a consequence, the long-term archival of data stored in multiple formats becomes an expensive and challenging task. In this paper, we demonstrate an alternative solution, namely migration of data to a single standards-based archive format. Data from NASA's Earth Observing System (EOS) Data Centers formatted in Hierarchical Data Format (HDF) are used in the demonstration.