Time–Frequency Cepstral Features and Heteroscedastic Linear Discriminant Analysis for Language Recognition

The shifted delta cepstrum (SDC) is a widely used feature extraction for language recognition (LRE). With a high context width due to incorporation of multiple frames, SDC outperforms traditional delta and acceleration feature vectors. However, it also introduces correlation into the concatenated feature vector, which increases redundancy and may degrade the performance of backend classifiers. In this paper, we first propose a time-frequency cepstral (TFC) feature vector, which is obtained by performing a temporal discrete cosine transform (DCT) on the cepstrum matrix and selecting the transformed elements in a zigzag scan order. Beyond this, we increase discriminability through a heteroscedastic linear discriminant analysis (HLDA) on the full cepstrum matrix. By utilizing block diagonal matrix constraints, the large HLDA problem is then reduced to several smaller HLDA problems, creating a block diagonal HLDA (BDHLDA) algorithm which has much lower computational complexity. The BDHLDA method is finally extended to the GMM domain, using the simpler TFC features during re-estimation to provide significantly improved computation speed. Experiments on NIST 2003 and 2007 LRE evaluation corpora show that TFC is more effective than SDC, and that the GMM-based BDHLDA results in lower equal error rate (EER) and minimum average cost (Cavg) than either TFC or SDC approaches

Induction of PtoCDKB and PtoCYCB transcription by temperature during cambium reactivation in Populus tomentosa Carr.

Cell cycle progression requires interaction between cyclin-dependent kinase B (CDKB) and cyclin B (CYCB). The seasonal expression patterns of the CDKB and CYCB homologues from Populus tomentosa Carr. were investigated, and effects of temperature and exogenous indole-3-acetic acid (IAA) on their expression were further studied in water culture experiments. Based on the differential responses of dormant cambium cells to exogenous IAA, four stages of cambium dormancy were confirmed for P. tomentosa: quiescence 1 (Q1), rest, quiescence 2-1 (Q2-1), and quiescence 2-2 (Q2-2). PtoCDKB and PtoCYCB transcripts were strongly expressed in the active phases, weakly in Q1, and almost undetectable from rest until late Q2-2. Climatic data analysis showed a correlation between daily air temperature and PtoCDKB and PtoCYCB expression patterns. Water culture experiments with temperature treatment further showed that a low temperature (4 °C) kept PtoCDKB and PtoCYCB transcripts at undetectable levels, while a warm temperature (25 °C) induced their expression in the cambium region. Meanwhile, water culture experiments with exogenous IAA treatment showed that induction of PtoCDKB and PtoCYCB transcription was independent of exogenous IAA. The results suggest that, in deciduous hardwood P. tomentosa growing in a temperate zone, the temperature in early spring is a vital environmental factor for cambium reactivation. The increasing temperature in early spring may induce CDKB and CYCB homologue transcription in the cambium region, which is necessary for cambium cell division

Proteomic Analysis of Larval Midgut from the Silkworm (Bombyx mori)

The midgut is the major organ for food digestion, nutrient absorption and also a barrier for foreign substance. The 5th-instar larval stage of silkworm is very important for larval growth, development, and silk production. In the present study, we used 2-DE and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to analyze the midgut proteins from the 5th-instar larvae as well as the midgut proteins under starvation condition. A total of 96 proteins were identified in this study; and among them, 69 proteins were observed in midgut for the first time. We also found that the silkworm larval midgut responded to starvation by producing a 10 kDa heat shock protein and a diapause hormone precursor

The instant effect of embodiment via mirror visual feedback on electroencephalogram-based brain connectivity changes: A pilot study

The therapeutic efficacy of mirror visual feedback (MVF) is attributed to the perception of embodiment. This study intends to investigate the instantaneous effect of embodiment on brain connectivity. Twelve healthy subjects were required to clench and open their non-dominant hands and keep the dominant hands still during two experimental sessions. In the first session, the dominant hand was covered and no MVF was applied, named the sham-MVF condition. Random vibrotactile stimulations were applied to the non-dominant hand with MVF in the subsequent session. Subjects were asked to pedal while having embodiment perception during motor tasks. As suggested by previous findings, trials of no vibration and continuous vibration were selected for this study, named the condition of MVF and vt-MVF. EEG signals were recorded and the alterations in brain connectivity were analyzed. The average node degrees of sham-MVF, MVF, and vt-MVF conditions were largely different in the alpha band (9.94, 11.19, and 17.37, respectively). Further analyses showed the MVF and vt-MVF had more nodes with a significantly large degree, which mainly occurred in the central and the visual stream involved regions. Results of network metrics showed a significant increment of local and global efficiency, and a reduction of characteristic path length for the vt-MVF condition in the alpha and beta bands compared to sham-MVF, and in the alpha band compared to MVF. Similar trends were found for MVF condition in the beta band compared to sham-MVF. Moreover, significant leftward asymmetry of global efficiency and rightward asymmetry of characteristic path length was reported in the vt-MVF condition in the beta band. These results indicated a positive impact of embodiment on network connectivity and neural communication efficiency, which reflected the potential mechanisms of MVF for new insight into neural modulation

Differential regulation of auxin and cytokinin during the secondary vascular tissue regeneration in Populus trees

Tissue regeneration upon wounding in plants highlights the developmental plasticity of plants. Previous studies have described the morphological and molecular changes of secondary vascular tissue (SVT) regeneration after large-scale bark girdling in trees. However, how phytohormones regulate SVT regeneration is still unknown. Here, we established a novel in vitro SVT regeneration system in the hybrid aspen (Populus tremula x Populus tremuloides) clone T89 to bypass the limitation of using field-grown trees. The effects of phytohormones on SVT regeneration were investigated by applying exogenous hormones and utilizing various transgenic trees. Vascular tissue-specific markers and hormonal response factors were also examined during SVT regeneration. Using this in vitro regeneration system, we demonstrated that auxin and cytokinin differentially regulate phloem and cambium regeneration. Whereas auxin is sufficient to induce regeneration of phloem prior to continuous cambium restoration, cytokinin only promotes the formation of new phloem, not cambium. The positive role of cytokinin on phloem regeneration was further confirmed in cytokinin overexpression trees. Analysis of a DR5 reporter transgenic line further suggested that cytokinin blocks the re-establishment of auxin gradients, which is required for the cambium formation. Investigation on the auxin and cytokinin signalling genes indicated these two hormones interact to regulate SVT regeneration. Taken together, the in vitro SVT regeneration system allows us to make use of various molecular and genetic tools to investigate SVT regeneration. Our results confirmed that complementary auxin and cytokinin domains are required for phloem and cambium reconstruction.Peer reviewe

Primary intramedullary melanocytoma presenting with lower limbs, defecation, and erectile dysfunction:A case report and review of the literature

BACKGROUND: Primary intramedullary melanocytoma is an exceedingly rare type of primary melanocytic tumor in the central nervous system. Unfortunately, primary intramedullary melanocytoma lacks specificity in clinical symptoms and imaging features and there is currently no standard strategy for diagnosis or treatment. CASE SUMMARY: A 52-year-old male patient suffered from weakness and numbness involving the bilateral lower limbs for 18 mo, and defecation and erectile dysfunction for 6 mo. Furthermore, these symptoms started to worsen for the last 3 mo. Preoperative magnetic resonance imaging (MRI) revealed an intramedullary tumor located at the T9-T10 level. In subsequently surgery, the maximal safe resection extent approached to 98%. The lesion was confirmed to be melanocytoma by pathological examination. In addition, the possibility of original melanocytoma outside the spinal cord was excluded after the examination of the whole body. Therefore, a diagnosis of primary intramedullary melanocytoma was established. The patient refused to accept radiotherapy or Gamma Knife, but MRI examination on July 28, 2020 showed no sign of development. In addition, on April 10, 2021, the recent review showed that the disorder of defecation and lower limbs improved further but erectile dysfunction benefited a little from the surgery. CONCLUSION: After diagnosing intramedullary melanocytoma by postoperative pathology, the inspection of the whole body contributed to excluding the possibility of metastasis from other regions and further suggested a diagnosis of primary intramedullary melanocytoma. Complete resection, adjuvant radiation, and regular review are critical. In addition, maximal safe resection also benefits prognosis while the tumor is difficult to be resected totally

BigDataBench: a Big Data Benchmark Suite from Internet Services

As architecture, systems, and data management communities pay greater attention to innovative big data systems and architectures, the pressure of benchmarking and evaluating these systems rises. Considering the broad use of big data systems, big data benchmarks must include diversity of data and workloads. Most of the state-of-the-art big data benchmarking efforts target evaluating specific types of applications or system software stacks, and hence they are not qualified for serving the purposes mentioned above. This paper presents our joint research efforts on this issue with several industrial partners. Our big data benchmark suite BigDataBench not only covers broad application scenarios, but also includes diverse and representative data sets. BigDataBench is publicly available from http://prof.ict.ac.cn/BigDataBench . Also, we comprehensively characterize 19 big data workloads included in BigDataBench with varying data inputs. On a typical state-of-practice processor, Intel Xeon E5645, we have the following observations: First, in comparison with the traditional benchmarks: including PARSEC, HPCC, and SPECCPU, big data applications have very low operation intensity; Second, the volume of data input has non-negligible impact on micro-architecture characteristics, which may impose challenges for simulation-based big data architecture research; Last but not least, corroborating the observations in CloudSuite and DCBench (which use smaller data inputs), we find that the numbers of L1 instruction cache misses per 1000 instructions of the big data applications are higher than in the traditional benchmarks; also, we find that L3 caches are effective for the big data applications, corroborating the observation in DCBench.Comment: 12 pages, 6 figures, The 20th IEEE International Symposium On High Performance Computer Architecture (HPCA-2014), February 15-19, 2014, Orlando, Florida, US

Characterization and specificity of the linear epitope of the enterovirus 71 VP2 protein

10.1186/1743-422X-9-55Virology Journal95