Accuracy of Mean Value of Central Venous Pressure from Monitor Digital Display: Influence of Amplitude of Central Venous Pressure during Respiration

Background A simple measurement of central venous pressure(CVP)-mean by the digital monitor display has become increasingly popular.However,the agreement between CVP-mean and CVP-end(a standard method of CVP measurement by analyzing the waveform at end-expiration)is not well determined.This study was designed to identify the relationship between CVP-mean and CVP-end in critically ill patients and to introduce a new parameter of CVP amplitude(ΔCVP=CVPmax-CVPmin)during the respiratory period to identify the agreement/disagreement between CVP-mean and CVP-end.Methods In total,291 patients were included in the study.CVP-mean and CVP-end were obtained simultaneously from each patient.CVP measurement difference(|CVP-mean-CVP-end|)was defined as the difference between CVP-mean and CVP-end.TheΔCVP was calculated as the difference between the peak(CVPmax)and the nadir value(CVPmin)during the respiratory cycle,which was automatically recorded on the monitor screen.Subjects with|CVP-mean-CVP-end|≥2 mm Hg were divided into the inconsistent group,while subjects with|CVP-mean-CVP-end|2 mm Hg were divided into the consistent group.ResultsΔCVP was significantly higher in the inconsistent group[7.17(2.77)vs.5.24(2.18),P0.001]than that in the consistent group.There was a significantly positive relationship betweenΔCVP and|CVP-mean-CVP-end|(r=0.283,P 0.0001).Bland-Altman plot showed the bias was-0.61 mm Hg with a wide 95%limit of agreement(-3.34,2.10)of CVP-end and CVP-mean.The area under the receiver operating characteristic curves(AUC)ofΔCVP for predicting|CVP-mean-CVP-end|≥2 mm Hg was 0.709.With a high diagnostic specificity,usingΔCVP3 to detect|CVP-mean-CVP-end|lower than 2mm Hg(consistent measurement)resulted in a sensitivity of 22.37%and a specificity of 93.06%.UsingΔCVP8 to detect|CVP-mean-CVPend|8 mm Hg(inconsistent measurement)resulted in a sensitivity of 31.94%and a specificity of 91.32%.Conclusions CVP-end and CVP-mean have statistical discrepancies in specific clinical scenarios.ΔCVP during the respiratory period is related to the variation of the two CVP methods.A highΔCVP indicates a poor agreement between these two methods,whereas a lowΔCVP indicates a good agreement between these two methods.

Design of recognition algorithm for multiclass digital display instrument based on convolution neural network

Digital display instrument identification is a crucial approach for automating the collection of digital display data.In this study,we propose a digital display area detection CTPNpro algorithm to address the problem of recognizing multiclass digital display instruments.We developed a multiclass digital display instrument recognition algorithm by combining the character recognition network constructed using a convolutional neural network and bidirectional variable-length long short-term memory(LSTM).First,the digital display region detection CTPNpro network framework was designed based on the CTPN network architecture by introducing feature fusion and residual structure.Next,the digital display instrument identification network was constructed based on a convolutional neural network using twoway LSTM and Connectionist temporal classification(CTC)of indefinite length.Finally,an automatic calibration system for digital display instruments was built,and a multiclass digital display instrument dataset was constructed by sampling in the system.We compared the performance of the CTPNpro algorithm with other methods using this dataset to validate the effectiveness and robustness of the proposed algorithm.

Field emission digital display tube with nano-graphite film cathode

The field emission digital display tube with a nano-crystalline graphite cold cathode is designed and fabricated. Under the control of the driving circuits, a dynamic digital display with uniform luminance distribution is realized. The luminance of the character segments is 190 cd/m2 at the operating voltage of 900 V. And the stable emission is attained with a fluctuation of about 3% at an average segment current of 75 μA. The results demonstrate that nano-crystalline graphite film is a promising material for cold cathode.

Era of the 4D animal model

Revealing the entire dynamics of pathogenesis is critical for understanding,preventing and treating human disease but is limited by systematic clinical sampling.This drawback can be overcome with animal model studies.Recent advances in phenotyping,omics and bioinformatics technologies promote the development of the 4D animal model to simulate and digitally display the spatiotemporal landscapes of phenotypes and molecular dynamics in human diseases and reveal novel targets for diagnosis and therapy.In this commentary,the origin,supporting technologies,content,function and application,and advantages of 4D animal models over clinical studies and traditional animal models,as well as their limitations,are presented.

Identification and expression of a novel human testis-specific gene by digital differential display

Background Evidence for the importance of genetic factors in male infertility is accumulating This study was designed to identify a novel testis specific gene related to spermatogenesis by a new strategy of digital differential display (DDD) Methods Based on the generation of expressed sequenced tags (ESTs), comparing the testis libraries with other tissue or cell line libraries by the DDD program, we identified a new contig of the ESTs which were derived from testis libraries and represented a novel gene Multi tissue RT PCR was performed to analyse its tissue specific expression The full length cDNA of the new gene was obtained using the BLAST program Sequencing was performed and the result was analysed Semi quantitative RT PCR and Northern blot analyseis of mRNA from differential normal tissues were performed to clarify the expression pattern of the new gene The sequence of the opening reading frame was integrated into the pQE 30 vector expressed in Escherichia coil strain M15(pREP4) With IPTG induction, the target protein was detected Results A full length cDNA sequence of the new gene named SPATA12 (GeneBank accession number AY221117) in human testis was identified SPATA12 was 2430 bp in length, located in chromosome 3p21 1 3p21 2 The sequence of the opening reading frame was 676-1248 bp, as was confirmed by RT PCR and sequencing The cDNA encodes a novel protein of 190 amino acids with a theoretical molecular weight of 20 417 8 and isoelectric point of 5 23 The sequence has no significant homology with any known protein in databases Semi quantitative RT PCR and Northern blot analyses of multiple tissues showed that SPATA12 was expressed significantly in normal human testis The expression recombinant of SPATA12 was constructed and a high level of the histidine tagged fusion protein was obtained Conclusions DDD can be confirmed by SPATA12 as a novel computational biology based approach for identification of the testis specific expression genes SPATA12 may function as a testicular germ cell associated gene that plays some roles in spermatogenesis Moreover, a great amount of SPATA12 protein could be obtained by the gene recombination technique, thus providing a reliable foundation for investigating the biological function of this new protein

Design of Slant-Form Tool in Precision Reuse of Digital Paper Display

A reuse fabrication module using micro electroetching as a precision machining process with a new design of a slant-form tool to remove the defective indium-tin-oxide （ITO） nanostructure from the optical polyethyleneterephthalate （PET） surfaces of digital paper display is presented in current studies. The low yield of ITO thin film deposition is an important factor in optoelectronic semiconductor production. The adopted precision reuse process requires only a short period of time to remove the ITO nanostructure easily and cleanly, which is based on technical and economical considerations and is highly efficient. In the current experiment, a large inclined angle of the cathode and a small end radius of the anode take less time for the same amount of ITO removal. A higher feed rate of the optical PET diaphragm combines with enough electric power to drive fast micro electroetching. A small rotational diameter of the anode accompanied by a small width of the cathode corresponds to a higher removal rate for the ITO nanostructure. A pulsed direct current can improve the effect of dreg discharge and is advantageous to couple this current with the fast feed rate of the workpiece. This improvement is associated with an increase in current rating. High rotational speed of the slant-form tool can improve the effect of dregs discharge and is advantageous to associate with the fast feed rate of the workpiece （optical PET diaphragm）.

A grey scale conversion algorithm for digital sonar display system

It is proved that the bearing history display is an effective method to detect weak signal. There is an interface between multibeam data and brightness modulation display system in digital sonar. The system gain obtained from signal processing system may be lost in this interface. A right choice of conversion algorithm will reduce this lose to minimum. The Grey Scale Conversion ( GSC) algorithm proposed in this paper is a real time digital operation technique. This technique can be used to improve the detection ability for weak signals, in the meantime there is no serious effect on strong signal detection. The method described in this papr is easy to implement in hardware. The simulation results with a computer show a good agreement with the theoretical analysis. A brief outline of hardware design is also illustrated.