This work introduces the use of compressed sensing (CS) algorithms for data compression in wireless sensors to address the energy and telemetry bandwidth constraints common to wireless sensor nodes. ...Circuit models of both analog and digital implementations of the CS system are presented that enable analysis of the power/performance costs associated with the design space for any potential CS application, including analog-to-information converters (AIC). Results of the analysis show that a digital implementation is significantly more energy-efficient for the wireless sensor space where signals require high gain and medium to high resolutions. The resulting circuit architecture is implemented in a 90 nm CMOS process. Measured power results correlate well with the circuit models, and the test system demonstrates continuous, on-the-fly data processing, resulting in more than an order of magnitude compression for electroencephalography (EEG) signals while consuming only 1.9 μW at 0.6 V for sub-20 kS/s sampling rates. The design and measurement of the proposed architecture is presented in the context of medical sensors, however the tools and insights are generally applicable to any sparse data acquisition.
Microbial infectious diseases continue to be one of the leading causes of morbidity and mortality. It has been estimated that microbial species comprise about 60% of the Earth's biomass. This, ...together with the fact that their genetic, metabolic and physiological diversity is extraordinary, makes them a major threat to the health and development of populations across the world. Widespread antibiotic resistance, the emergence of new pathogens in addition to the resurgence of old ones, and the lack of effective new therapeutics exacerbate the problems. Thus, the need to discover and develop new antimicrobial agents is critical to improve mankind's future health. Plant secondary metabolites (PSMs) offer particular promise in this sense. Plant Kingdom could be considered a rich source of the most diverse structures (e.g. there are more than 12,000 known alkaloids, more than 8,000 phenolic compounds and over 25,000 different terpenoids), many of which were proven to possess strong antimicrobial properties (e.g. thymol, eurabienol, etc.). In many instances, PSMs can be easily isolated from the plant matrix, either in pure state or in the form of mixtures of chemically related compounds. What is also important is that the development of bacterial resistance toward natural plant products (that are generally regarded as eco-friendly) has been thus far documented in a very limited number of cases (e.g. for reserpine). Having all of the mentioned advantages of PSMs as potential antimicrobials in mind, a major question arises: why is it that there are still no commercially available or commonly used antibiotics of plant origin? This review tries to give a critical answer to this question by considering potential mechanisms of antimicrobial action of PSMs (inhibition of cell wall or protein synthesis, inducing leakage from the cells by tampering with the function of the membranes, interfering with intermediary metabolisms or DNA/RNA synthesis/function), as well as their physical and chemical properties (e.g. hydrophilicity/lipophilicity, chemical stability). To address the possible synergistic/antagonistic effects between PSMs and with standard antibiotics, special attention has been given to the antimicrobial activity of PSM-mixtures (e.g. essential oils, plant extracts). Moreover, possible ways of overcoming some of PSMs molecular limitations in respect to their usage as potential antibiotics were also discussed (e.g. derivatization that would enable fine tuning of certain molecular characteristics).
The human gastrointestinal (GI) tract microbiota plays a pivotal role in our health. For more than a decade a major input for describing the diversity of the GI tract microbiota has been derived from ...the application of small subunit ribosomal RNA (SSU rRNA)-based technologies. These not only provided a phylogenetic framework of the GI tract microbiota, the majority of which has not yet been cultured, but also advanced insights into the impact of host and environmental factors on the microbiota community structure and dynamics. In addition, it emerged that GI tract microbial communities are host and GI tract location-specific. This complicates establishing relevant links between the host's health and the presence or abundance of specific microbial populations and argues for the implementation of novel high-throughput technologies in studying the diversity and functionality of the GI tract microbiota. Here, we focus on the recent developments and applications of phylogenetic microarrays based on SSU rRNA sequences and metagenomics approaches exploiting rapid sequencing technologies in unravelling the secrets of our GI tract microbiota.
IntroductionDelirium is an important mental disorder, especially in intensive care units, which negatively affects the morbidity and mortality. Subjective clinical assessment of patients by ...non-psychiatric health professionals in intensive care units is insufficient to detect and measure delirium. Therefore, different scoring scales have been developed to assess delirium. A brief examination cannot entirely differentiate between a delirium, especially of organic origin, versus a psychotic break. Measurement scales for delirium are not routinely used. However, evidence shows that objective assessment of delirium contributes to its early detection in intensive care and the initiation of appropriate treatment.ObjectivesTo show the importance of using validated scales in delirium patients.MethodsA case report.ResultsA 63-year-old male patient was admitted to our psychiatry ward after being evaluated by the local internal medicine specialist for confusion and suicidal ideation. He wrote a suicide note and had a positive family history for mental disorder (the brother has schizophrenia). During the initial mental state examination, the patient showed general disorientation, thought dissociation and defunct reality testing. A profound laboratory testing did not show any meaningful changes. A CT-scan was conducted that showed no pathologic alteration. Firstly, the patient was treated as a psychotic case, with haloperidol and diazepam parenterally. After no evident improvement of his mental state the Delirium Detection Scale (DDS) was used. Eliciting a highly positive result, the patient was re-evaluated as an (somatic) delirium. Therefore, a neurologist was consulted and a lumbar puncture performed. The cerebrospinal fluid (CSF) was indicative for a viral meningitis. So, the patient was admitted to the Infectious Disease Unit. As no treatment showed results an additional CSF panel for paraneoplastic antibodies. This came back very positive for AntiHu – a marker for small-cell lung carcinoma. Next day’s thoracic CT scan revealed a massive carcinoma with no proliferation. At last, the patient was transferred to the pneumo-oncological unit where he received pulse therapy with methylprednisolone. After which, his mental state recovered fully and the patient started chemotherapy.ConclusionsDelirium is a complex medical situation. It is an emergency which is classified in the ICD as a mental disorder. However, it demands medical and non-psychiatric therapy swiftly. Only, a swift and precise diagnosis can be a leading light here. The use of diagnostic scales should be encouraged as shown in this case report.Disclosure of InterestNone Declared
Data transport across short electrical wires is limited by both bandwidth and power density, which creates a performance bottleneck for semiconductor microchips in modern computer systems--from ...mobile phones to large-scale data centres. These limitations can be overcome by using optical communications based on chip-scale electronic-photonic systems enabled by silicon-based nanophotonic devices. However, combining electronics and photonics on the same chip has proved challenging, owing to microchip manufacturing conflicts between electronics and photonics. Consequently, current electronic-photonic chips are limited to niche manufacturing processes and include only a few optical devices alongside simple circuits. Here we report an electronic-photonic system on a single chip integrating over 70 million transistors and 850 photonic components that work together to provide logic, memory, and interconnect functions. This system is a realization of a microprocessor that uses on-chip photonic devices to directly communicate with other chips using light. To integrate electronics and photonics at the scale of a microprocessor chip, we adopt a 'zero-change' approach to the integration of photonics. Instead of developing a custom process to enable the fabrication of photonics, which would complicate or eliminate the possibility of integration with state-of-the-art transistors at large scale and at high yield, we design optical devices using a standard microelectronics foundry process that is used for modern microprocessors. This demonstration could represent the beginning of an era of chip-scale electronic-photonic systems with the potential to transform computing system architectures, enabling more powerful computers, from network infrastructure to data centres and supercomputers.
We describe a molecular automaton, called MAYA, which encodes a version of the game of tic-tac-toe and interactively competes against a human opponent. The automaton is a Boolean network of ...deoxyribozymes that incorporates 23 molecular-scale logic gates and one constitutively active deoxyribozyme arrayed in nine wells (3x3) corresponding to the game board. To make a move, MAYA carries out an analysis of the input oligonucleotide keyed to a particular move by the human opponent and indicates a move by fluorescence signaling in a response well. The cycle of human player input and automaton response continues until there is a draw or a victory for the automaton. The automaton cannot be defeated because it implements a perfect strategy.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Inspired by the theory of compressed sensing and employing random channel access, we propose a distributed energy-efficient sensor network scheme denoted by Random Access Compressed Sensing (RACS). ...The proposed scheme is suitable for long-term deployment of large underwater networks, in which saving energy and bandwidth is of crucial importance. During each frame, a randomly chosen subset of nodes participate in the sensing process, then share the channel using random access. Due to the nature of random access, packets may collide at the fusion center. To account for the packet loss that occurs due to collisions, the network design employs the concept of sufficient sensing probability. With this probability, sufficiently many data packets - as required for field reconstruction based on compressed sensing - are to be received. The RACS scheme prolongs network life-time while employing a simple and distributed scheme which eliminates the need for scheduling.
•A new natural product 5-phenylpentyl isothiocyanate (PhPeITC) was found in horseradish.•The first direct proof of the existence of a 5-phenylpentyl glucosinolate in nature.•PhPeITC and four related ...isothiocyanates were synthesised and extensively tested.•PhPeITC possesses spasmolytic activity 100 times more potent than papaverine.•Horseradish constituents showed significant cytotoxicity and antimicrobial activity.
Detailed analyses of horseradish autolysates led to the identification of a new natural product, 5-phenylpentyl isothiocyanate (PhPeITC). The structural assignment was corroborated by synthesis, and the identity unequivocally established by spectral means. The occurrence of PhPeITC is the first direct proof of the existence of a 5-phenylpentyl glucosinolate in the aerial parts of this species as one of the possible “mustard oil” precursors. To verify its possible contribution to the horseradish functional food status, horseradish above- and underground autolysates, together with five ω-phenylalkyl isothiocyanates were tested for their spasmolytic, cytotoxic and antimicrobial activities. Specifically, the cytotoxic effect on Caco-2, HeLa (cancer) and MDCK (non-cancer) cell lines was established. Additionally, the five tested ITCs exerted significant spasmolytic activity (on rat distal colon), with PhPeITC being almost 100 times more potent than papaverine. A non-selective antimicrobial activity of all ITCs was revealed in the case of 6 bacterial and 2 fungal strains.
Multiple-input-multiple-output (MIMO) techniques have been actively pursued recently in underwater acoustic communications to increase the data rate over the bandwidth-limited channels. In this ...communication, we present a MIMO system design, where spatial multiplexing is applied with orthogonal-frequency-division-multiplexing (OFDM) signals. The proposed receiver works on a block-by-block basis, where null subcarriers are used for Doppler compensation, pilot subcarriers are used for channel estimation, and a MIMO detector consisting of a hybrid use of successive interference cancellation and soft minimum mean square error (MMSE) equalization is coupled with low-density parity-check (LDPC) channel decoding for iterative detection on each subcarrier. The proposed design has been tested using data recorded from three different experiments. A spectral efficiency of 3.5 b/s/Hz was approached in one experiment, while a data rate of 125.7 kb/s over a bandwidth of 62.5 kHz was achieved in another. These results suggest that MIMO-OFDM is an appealing solution for high-data-rate transmissions over underwater acoustic channels.
Bioimpedance modeling with equivalent electrical circuits has an important role in various biomedical applications, as it facilitates understanding of underlying physical and electrochemical ...processes in applications such as body composition measurements and assessment of clinical conditions. However, estimation of model parameter values is not a straightforward task, especially when complex circuits with fractional-order components (e.g. constant phase elements) are used. In this paper, we propose a low-complexity method for parameter estimation of the Cole-impedance model suitable for low-cost embedded hardware (e.g. 8-bit microcontrollers). Our approach uses only the measured real and imaginary impedance, without any specific software package/toolbox, or initial values provided by the user. The proposed method was validated with synthetic (noiseless and noisy) data and experimental right-side, hand-to-foot bioimpedance data from a healthy adult participant. Moreover, the proposed method was compared in terms of accuracy with the recently published relevant work and commercial Electrical Impedance Spectroscopy software (Bioimp 2.3.4). The performance evaluation in terms of complexity (suitable for deployment for the microcontroller-based platform with 256 kB of RAM and 16 MHz clock speed), execution time (18 seconds for dataset with 256 points) and cost (<25 USD) confirms the proposed method in regards to reliable bioimpedance processing using embedded hardware.
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