Experience-Dependent Modulation of C. elegans Behavior by Ambient Oxygen

SummaryBackground: Ambient oxygen (O2) influences the behavior of organisms from bacteria to man. In C. elegans, an atypical O2 binding soluble guanylate cyclase (sGC), GCY-35, regulates O2 responses. However, how acute and chronic changes in O2 modify behavior is poorly understood.Results: Aggregating C. elegans strains can respond to a reduction in ambient O2 by a rapid, reversible, and graded inhibition of roaming behavior. This aerokinetic response is mediated by GCY-35 and GCY-36 sGCs, which appear to become activated as O2 levels drop and to depolarize the AQR, PQR, and URX neurons. Coexpression of GCY-35 and GCY-36 is sufficient to transform olfactory neurons into O2 sensors. Natural variation at the npr-1 neuropeptide receptor alters both food-sensing and O2-sensing circuits to reconfigure the salient features of the C. elegans environment. When cultivated in 1% O2 for a few hours, C. elegans reset their preferred ambient O2, seeking instead of avoiding 0%–5% O2. This plasticity involves reprogramming the AQR, PQR, and URX neurons.Conclusions: To navigate O2 gradients, C. elegans can modulate turning rates and speed of movement. Aerotaxis can be reprogrammed by experience or engineered artificially. We propose a model in which prolonged activation of the AQR, PQR, and URX neurons by low O2 switches on previously inactive O2 sensors. This enables aerotaxis to low O2 environments and may encode a “memory” of previous cultivation in low O2

A novel anti-mycobacterial function of mitogen-activated protein kinase phosphatase-1

<p>Abstract</p> <p>Background</p> <p><it>Mycobacterium tuberculosis </it>(MTB) is a major cause of morbidity and mortality in the world. To combat against this pathogen, immune cells release cytokines including tumor necrosis factor-α (TNF-α), which is pivotal in the development of protective granulomas. Our previous results showed that Bacillus Calmette Guerin (BCG), a mycobacterium used as a model to investigate the immune response against MTB, stimulates the induction of TNF-α via mitogen-activated protein kinase (MAPK) in human blood monocytes. Since MAPK phosphatase-1 (MKP-1) is known to regulate MAPK activities, we examined whether MKP-1 plays a role in BCG-induced MAPK activation and cytokine expression.</p> <p>Results</p> <p>Primary human blood monocytes were treated with BCG and assayed for MKP-1 expression. Our results demonstrated that following exposure to BCG, there was an increase in the expression of MKP-1. Additionally, the induction of MKP-1 was regulated by p38 MAPK and extracellular signal-regulated kinase 1 and 2 (ERK1/2). Surprisingly, when MKP-1 expression was blocked by its specific siRNA, there was a significant decrease in the levels of phospho-MAPK (p38 MAPK and ERK1/2) and TNF-α inducible by BCG.</p> <p>Conclusions</p> <p>Since TNF-α is pivotal in granuloma formation, the results indicated an unexpected positive function of MKP-1 against mycobacterial infection as opposed to its usual phosphatase activity.</p

A Gaussian process based data modelling and fusion method for multisensor coordinate measuring machines

Multisensor measurement technology is an emerging technology which makes use of combinations of two or more different types of sensor probes so as to further enhance the measurement capability of the traditional single sensor coordinate measurement machines (CMMs). The sensors can complement each other’s limitations and improve the measurement accuracy. Nowadays, the applications of multisensor CMMs are becoming more and more widespread and many CMM manufacturers are developing multisensor CMMs in their advanced production lines. For instances, ZEISS O-INSPECT [1] equips with a contact sensor, imaging sensor and white light distance sensor, which is able to provide a fast inspection by the image sensor and high accuracy 3D measurement results by the contact sensor and white light distance sensor. Werth VideoCheck [2], is designed to equip with many kinds of sensors such as trigger probe, fiber probe and video sensor which provides the measurement ability of small features with the help of the small-diameter fiber probe in the scale down to 20 μm, as well as a quick checking with the fast trigger probe and image sensor. Hexagon Optiv Classic [3] provides a vision sensor and a tough trigger probe, while Nikon [4] enhances the true 3D multi-sensor measurement by combining vision sensor, laser auto-focus sensor, tactile sensor and rotary indexer. The measurement range, resolution and flexibility are largely enhanced by the complementary of the different characteristics of various sensors. The combination of different types of sensors extends the measurement ability such as accuracy and measurement range of the CMMs. However, most of the multisensor CMMs are lack of an optimal strategy to perform multisensor measurement and fusion of data from different sensors. Some of the studies for multisensor CMM focused on complementary measurement for special geometrical features. Nashman et al. [5] used a camera sensor to locate and measure the feature such as object edges, corners and centroids while the touch sensor was used to measure other part of the object. The touch sensor was highly accurate with little noise. However, it could not measure sharp features such as edges and corners. Combining these two sensors enable the capability to gather high bandwidth global information and to obtain high accurate measurement information. Zexiao et al. [6] used a multi-probe system which consists of a structure light sensor and a trigger probe to measure multiple features including edges. However, the edges were not directly measured while they were generated by fitting the surfaces using the measured points on the relatively smooth surfaces instead. This paper presents a Gaussian process based data modelling and data fusion (GP-DMF) method which first estimates the mean surfaces and uncertainties of the datasets obtained from different sensors and combines the two measurement data into a single one with associated uncertainty. A series of simulation and measurement experiments have been conducted to verify the technical feasibility of the method. The results show that the fused data with a lower uncertainty are obtained. The proposed GP-DMF method attempts to provide a generalized data-orientation multi-sensor measurement method which does not rely on the sensor itself and this makes it having potential to be used in a wide application fields

How to improve performance in technology and innovation teams?

This paper presents a study that attempts to answer practical questions about work team performance issues. It considers organizational culture, team climate and manager behavior as the major factors affecting competencies and performance of team members. Theoretical background and practical implications are discussed here

Reproducibility of thoracic kyphosis measurements in patients with adolescent idiopathic scoliosis

BACKGROUND: Current surgical treatment for adolescent idiopathic scoliosis (AIS) involves correction in both the coronal and sagittal plane, and thorough assessment of these parameters is essential for evaluation of surgical results. However, various definitions of thoracic kyphosis (TK) have been proposed, and the intra- and inter-rater reproducibility of these measures has not been determined. As such, the purpose of the current study was to determine the intra- and inter-rater reproducibility of several TK measurements used in the assessment of AIS. METHODS: Twenty patients (90% females) surgically treated for AIS with alternate-level pedicle screw fixation were included in the study. Three raters independently evaluated pre- and postoperative standing lateral plain radiographs. For each radiograph, several definitions of TK were measured as well as L1–S1 and nonfixed lumbar lordosis. All variables were measured twice 14 days apart, and a mixed effects model was used to determine the repeatability coefficient (RC), which is a measure of the agreement between repeated measurements. Also, the intra- and inter-rater intra-class correlation coefficient (ICC) was determined as a measure of reliability. RESULTS: Preoperative median Cobb angle was 58° (range 41°–86°), and median surgical curve correction was 68% (range 49–87%). Overall intra-rater RC was highest for T2–T12 and nonfixed TK (11°) and lowest for T4–T12 and T5–T12 (8°). Inter-rater RC was highest for T1–T12, T1-nonfixed, and nonfixed TK (13°) and lowest for T5–T12 (9°). Agreement varied substantially between pre- and postoperative radiographs. Inter-rater ICC was highest for T4–T12 (0.92; 95% CI 0.88–0.95) and T5–T12 (0.92; 95% CI 0.88–0.95) and lowest for T1-nonfixed (0.80; 95% CI 0.72–0.88). CONCLUSIONS: Considerable variation for all TK measurements was noted. Intra- and inter-rater reproducibility was best for T4–T12 and T5–T12. Future studies should consider adopting a relevant minimum difference as a limit for true change in TK. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13013-017-0112-4) contains supplementary material, which is available to authorized users

An autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools

Meanwhile, in-situ measurement is of prime importance when trying to maintain the position of the workpiece for further compensation processes in order to improve the accuracy and efficiency of the precision machining of freeform surfaces. However, the coordinates of most of the machine tools with closed machine interfaces and control system are not accessible for users, which make it difficult to use the motion axes of the machine tool for in-situ measurement. This paper presents an autonomous multisensor in-situ metrology system for enabling the high dynamic range measurement capability of machine tools for freeform surfaces. It makes use of a designed tool path and an additional motion sensor to assist the registration of time-space data for the position estimation of a 2D laser scanner which measures the surface with a high lateral resolution and large area without the need to interface with the machine tool system. A prototype system was built and integrated into an ultra-precision polishing machine. Experimental results show that it measures freeform surfaces with high resolution, high repeatability, and large measurement range. The system not only improves the efficiency and accuracy of the precision machining process but also extends the capability of machine tools

Implementation of the compulsory universal testing scheme in Hong Kong: Mathematical simulations of a household-based pooling approach

This study aims to propose a pooling approach to simulate the compulsory universal RT-PCR test in Hong Kong and explore the feasibility of implementing the pooling method on a household basis. The mathematical model is initially verified, and then the simulation is performed under different prevalence rates and pooled sizes. The simulated population is based in Hong Kong. The simulation included 10,000,000 swab samples, with a representative distribution of populations in Hong Kong. The samples were grouped into a batch size of 20. If the entire batch is positive, then the group is further divided into an identical group size of 10 for re-testing. Different combinations of mini-group sizes were also investigated. The proposed pooling method was extended to a household basis. A representative from each household is required to perform the RT-PCR test. Results of the simulation replications, indicate a significant reduction (p &lt; 0.001) of 83.62, 64.18, and 48.46% in the testing volume for prevalence rate 1, 3, and 5%, respectively. Combined with the household-based pooling approach, the total number of RT-PCR is 437,304, 956,133, and 1,375,795 for prevalence rates 1, 3, and 5%, respectively. The household-based pooling strategy showed efficiency when the prevalence rates in the population were low. This pooling strategy can rapidly screen people in high-risk groups for COVID-19 infections and quarantine those who test positive, even when time and resources for testing are limited

Benefits and limitations of implementing Chronic Care Model (CCM) in primary care programs: a systematic review

Background: Chronic Care Model (CCM) has been developed to improve patients' health care by restructuring health systems in a multidimensional manner. This systematic review aims to summarize and analyse programs specifically designed and conducted for the fulfilment of multiple CCM components. We have focused on programs targeting diabetes mellitus, hypertension and cardiovascular disease. Method and results: This review was based on a comprehensive literature search of articles in the PubMed database that reported clinical outcomes. We included a total of 25 eligible articles. Evidence of improvement in medical outcomes and the compliance of patients with medical treatment were reported in 18 and 14 studies, respectively. Two studies demonstrated a reduction of the medical burden in terms of health service utilization, and another two studies reported the effectiveness of the programs in reducing the risk of heart failure and other cardiovascular diseases. However, CCMs were still restricted by limited academic robustness and social constraints when they were implemented in primary care. Higher professional recognition, tighter system collaborations and increased financial support may be necessary to overcome the limitations of, and barriers to CCM implementation. Conclusion: This review has identified the benefits of implementing CCM, and recommended suggestions for the future development of CCM