bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of transcriptional repressor activity of LexA in salt-stress responses of the cyanobacterium Synechocystis sp. PCC 6803
Authors: Takashima Kosuke , Nagao Syota , Kizawa Ayumi , Suzuki Takehiro , Dohmae Naoshi , Hihara Yukako 
Published: October 2020

AbstractDifferent from typical LexA repressors in heterotrophic bacteria exerting SOS response by auto-cleavage, cyanobacterial LexAs, especially that of Synechocystis sp. PCC 6803 (S.6803), have been suggested be involved in regulation of a number of genes related to various cellular processes, rather than the typical SOS regulon. When and how cyanobacterial LexAs are triggered to regulate its target genes have remained unknown. In this study, we found the profound repressing effect of LexA on salt-stress inducible genes in S.6803. The repressing activity of LexA was likely to persist during salt stress and the salt response of these genes was mainly achieved by other regulators than LexA, suggesting that the physiological role of LexA is fine-tuning of gene expression in response to environmental changes. Although the amount and oligomeric state of LexA were unchanged upon salt stress, two-dimensional electrophoresis and liquid chromatography-tandem mass spectrometry analyses detected a change in posttranslational modification in a small fraction of LexA molecules, possibly dephosphorylation of Ser173, after 30 min upon the upshift in salt concentration. Activity of LexA in S.6803 may be under gradual control by posttranslational modification to fine-tune gene expression, which is contrasted with the digital switching-off regulation by auto-cleavage in heterotrophic bacteria.
Molecular simulations unravel the molecular principles that mediate selective permeability of carboxysome shell protein
Authors: Faulkner Matthew , Szabó István , Weetman Samantha L. , Sicard Francois , Huber Roland G. , Bond Peter J. , Rosta Edina , Liu Lu-Ning 
Published: October 2020

AbstractBacterial microcompartments (BMCs) are nanoscale proteinaceous organelles that encapsulate enzymes from the cytoplasm using an icosahedral protein shell that resembles viral capsids. Of particular interest are the carboxysomes (CBs), which sequester the CO2-fixing enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) to enhance carbon assimilation. The carboxysome shell serves as a semi-permeable barrier for passage of metabolites in and out of the carboxysome to enhance CO2fixation. How the protein shell directs influx and efflux of molecules in an effective manner has remained elusive. Here we use molecular dynamics and umbrella sampling calculations to determine the free-energy profiles of the metabolic substrates, bicarbonate, CO2and ribulose bisphosphate and the product 3-phosphoglycerate associated with their transition through the major carboxysome shell protein CcmK2. We elucidate the electrostatic charge-based permeability and key amino acid residues of CcmK2 functioning in mediating molecular transit through the central pore. Conformational changes of the loops forming the central pore may also be required for transit of specific metabolites. The importance of these in-silico findings is validated experimentally by site-directed mutagenesis of the key CcmK2 residue Serine 39. This study provides insight into the mechanism that mediates molecular transport through the shells of carboxysomes, applicable to other BMCs. It also offers a predictive approach to investigate and manipulate the shell permeability, with the intent of engineering BMC-based metabolic modules for new functions in synthetic biology.
TAP2, a peptide antagonist of Toll-like receptor 4, attenuates pain and cartilage degradation in a monoiodoacetate-induced arthritis rat model
Authors: Park Hyewon , Hong Jinpyo , Yin Yuhua , Joo Yongbum , Kim Youngmo , Shin Juhee , Kwon Hyeok Hee , Shin Nara , Shin Hyo Jung , Beom Jaewon , Kim Dong Woon , Kim Jinhyun 
Published: October 2020

AbstractBecause inflammation in osteoarthritis (OA) is related to the Toll-like receptor 4 (TLR4) signaling cascades, TLR4 is a reasonable target for developing therapeutics for OA. Thus, we investigated whether TAP2, a peptide antagonist of TLR4, reduces the monoiodoacetate (MIA)-induced arthritic pain and cartilage degradation in rats. TLR4 expression of human OA chondrocytes and synoviocytes and the knee joint tissue of MIA-induced arthritis were evaluated. MIA-induced arthritic model using Sprague–Dawley rats (6 week-old-male) were treated with TAP2, a TLR4 antagonist, and evaluated with behavioral test, immunohistochemistry, and quantitative PCR. TLR4 was highly expressed in the knee joints of patients with OA and the MIA-induced rat model. Further, a single intraarticular injection of TAP2 (25 nmol/rat) molecules targeting TLR4 on day 7 after MIA injection dramatically attenuated pain behavior for about 3 weeks and reduced cartilage loss in the knee joints and microglial activation in the spinal dorsal horns. Likewise, the mRNA levels of TNFα and IL-1β, reactive oxygen species, and the expression of MMP13 in the knee joints of TAP2-treated rats was significantly decreased by TAP2 treatment compared with the control. Moreover, interestingly, the duration of OA pain relief by TAP2 was much longer than that of chemical TLR4 antagonists, such as C34 and M62812. In conclusion, TAP2 could effectively attenuate MIA-induced arthritis in rats by blocking TLR4 and its successive inflammatory cytokines and MMP13. Therefore, TAP2 could be a prospective therapeutic to treat patients with OA.
Experimental optimization of the energy for breast-CT with synchrotron radiation
Authors: Oliva Piernicola , Di Trapani Vittorio , Arfelli Fulvia , Brombal Luca , Donato Sandro , Golosio Bruno , Longo Renata , Mettivier Giovanni , Rigon Luigi , Taibi Angelo , Tromba Giuliana , Zanconati Fabrizio , Delogu Pasquale 
Published: October 2020

AbstractBreast Computed Tomography (bCT) is a three-dimensional imaging technique that is raising interest among radiologists as a viable alternative to mammographic planar imaging. In X-rays imaging it would be desirable to maximize the capability of discriminating different tissues, described by the Contrast to Noise Ratio (CNR), while minimizing the dose (i.e. the radiological risk). Both dose and CNR are functions of the X-ray energy. This work aims at experimentally investigating the optimal energy that, at fixed dose, maximizes the CNR between glandular and adipose tissues. Acquisitions of both tissue-equivalent phantoms and actual breast specimens have been performed with the bCT system implemented within the Syrma-3D collaboration at the Syrmep beamline of the Elettra synchrotron (Trieste). The experimental data have been also compared with analytical simulations and the results are in agreement. The CNR is maximized at energies around 26–28 keV. These results are in line with the outcomes of a previously presented simulation study which determined an optimal energy of 28 keV for a large set of breast phantoms with different diameters and glandular fractions. Finally, a study on photon starvation has been carried out to investigate how far the dose can be reduced still having suitable images for diagnostics.
The extremal pentagon-chain polymers with respect to permanental sum
Authors: Wu Tingzeng , Wang Hongge , Zhang Shanjun , Deng Kai 
Published: October 2020

AbstractThe permanental sum of a graphGcan be defined as the sum of absolute value of coefficients of permanental polynomial ofG. It is closely related to stability of structure of a graph, and its computing complexity is #P-complete. Pentagon-chain polymers is an important type of organic polymers. In this paper, we determine the upper and lower bounds of permanental sum of pentagon-chain polymers, and the corresponding pentagon-chain polymers are also determined.
Effectiveness of hysteroscopic resection of a uterine caesarean niche can be predicted: a prospective cohort study
Authors: Zhu Qian , He Xiaoqing , Jiang Ling , Liang Guiling , Zhu Chenfeng , Pan Hongjie , Zhang Jian , Huirne Judith Anna 
Published: October 2020

AbstractThis study aimed to develop and validate a model for the preoperative prediction of the effectiveness of hysteroscopic resection of a uterine cesarean niche in patients with postmenstrual spotting. The predictive model was developed in a primary prospective cohort consisting of 208 patients with niche treated by hysteroscopic resection. Multivariable logistic regression analysis was performed to develop the predictive model, which incorporated preoperative menstrual characteristics and magnetic resonance imaging (MRI) findings. Surgical efficacy was defined as a decrease in postmenstrual spotting duration of at least 3 days at the 3-month follow-up compared with baseline. The predictive model was presented with a nomogram, and the performance was assessed with respect to its calibration, discrimination, and clinical use. Internal validation was performed using tenfold cross-validation. The predictive factors in the final model were as follows: preoperative menstrual duration, thickness of the residual myometrium (TRM), length, TRM/thickness of the adjacent myometrium ratio, angle γ, area, and presence of a lateral branch of the niche. The model showed good performance in predicting the effectiveness of hysteroscopic niche resection. Incorporating the preoperative duration of the menstrual period and MRI findings of the niche into an easy-to-use nomogram facilitates the individualized prediction of the effectiveness of a hysteroscopic niche resection by 26 Fr resectoscope, but multicenter prospective studies are needed to validate it.
Reliability of pre-operative diffusion tensor imaging parameter measurements of the cervical spine in patients with cervical spondylotic myelopathy
Authors: Lee Eugene , Lee Joon Woo , Bae Yun Jung , Kim Hyo Jin , Kang Yusuhn , Ahn Joong Mo 
Published: October 2020

AbstractThe present study assessed test–retest and inter-observer reliability of diffusion tensor imaging (DTI) in cervical spondylotic myelopathy (CSM), as well as the agreement among measurement methods. A total 34 patients (12 men, 22 women; mean age, 58.7 [range 45–79] years) who underwent surgical decompression for CSM, with pre-operative DTI scans available, were retrospectively enrolled. Four observers independently measured fractional anisotropy (FA) values twice, using three different measurement methods. Test–retest and inter-observer reliability was assessed using intraclass correlation coefficients (ICCs). Overall, inter-observer agreements varied according to spinal cord level and the measurement methods used, and ranged from poor to excellent agreement (ICC = 0.374–0.821), with relatively less agreement for the sagittal region of interest (ROI) method. The radiology resident and neuro-radiologist group showed excellent test–retest reliability at almost every spinal cord level (ICC = 0.887–0.997), but inter-observer agreements varied from fair to good (ICC = 0.404–0.747). Despite excellent test–retest reliability of the ROI measurements, FA measurements in patients with CSM varied widely in terms of inter-observer reliability. Therefore, DTI parameter data should be interpreted carefully when applied clinically.
Relative fat mass at baseline and its early change may be a predictor of incident nonalcoholic fatty liver disease
Authors: Kim Hwi Young , Baik Su Jung , Lee Hye Ah , Lee Byoung Kwon , Lee Hye Sun , Kim Tae Hun , Yoo Kwon 
Published: October 2020

AbstractThe relationship between changes in body components and the risk of nonalcoholic fatty liver disease (NAFLD) is not fully understood. We investigated the effects of body components and subsequent changes on incident NAFLD at follow-up ultrasound scanning in a longitudinal cohort. We included 9967 participants without NAFLD at baseline who underwent serial health examinations. Sex-specific, weight-adjusted skeletal muscle index (SMI_Wt) was used. Mean follow-up duration was 48.5 ± 33.5 months. NAFLD developed in 2395 participants (24.0%). Body composition was measured using bioelectrical impedance analysis. The following baseline body components were significantly associated with incident NAFLD: the lowest and middle SMI_Wt tertiles in the normal-weight group (adjusted hazard ratio [aHR] = 2.20 and 1.54, respectively), and fat percentage in the normal-weight (aHR = 1.12), overweight (aHR = 1.05), and obese groups (aHR = 1.03) (all P < 0.05). Among 5,033 participants who underwent ≥ 3 health examinations, SMI_Wt increase between the first and second examinations was an independent protective factor against incident NAFLD in non-obese groups (P < 0.05). Increased fat percentage was an independent risk factor for incident NAFLD in all weight categories (P < 0.05). High fat mass at baseline may be a better predictor of incident NAFLD than muscle mass. Reciprocal changes in fat and muscle mass during the first year of follow-up predicted incident NAFLD in non-obese groups.
Differential processing of dissolved and particulate organic matter by deep-sea sponges and their microbial symbionts
Authors: Bart Martijn C. , de Kluijver Anna , Hoetjes Sean , Absalah Samira , Mueller Benjamin , Kenchington Ellen , Rapp Hans Tore , de Goeij Jasper M. 
Published: October 2020

AbstractDeep-sea sponges create hotspots of biodiversity and biological activity in the otherwise barren deep-sea. However, it remains elusive how sponge hosts and their microbial symbionts acquire and process food in these food-limited environments. Therefore, we traced the processing (i.e. assimilation and respiration) of 13C- and 15N-enriched dissolved organic matter (DOM) and bacteria by three dominant North Atlantic deep-sea sponges: the high microbial abundance (HMA) demosponge Geodia barretti, the low microbial abundance (LMA) demosponge Hymedesmia paupertas, and the LMA hexactinellid Vazella pourtalesii. We also assessed the assimilation of both food sources into sponge- and bacteria-specific phospholipid-derived fatty acid (PLFA) biomarkers. All sponges were capable of assimilating DOM as well as bacteria. However, processing of the two food sources differed considerably between the tested species: the DOM assimilation-to-respiration efficiency was highest for the HMA sponge, yet uptake rates were 4–5 times lower compared to LMA sponges. In contrast, bacteria were assimilated most efficiently and at the highest rate by the hexactinellid compared to the demosponges. Our results indicate that phylogeny and functional traits (e.g., abundance of microbial symbionts, morphology) influence food preferences and diet composition of sponges, which further helps to understand their role as key ecosystem engineers of deep-sea habitats.
Identification and characterization of a new isoform of small GTPase RhoE
Authors: Dai Yuan , Luo Weijia , Yue Xiaojing , Ma Wencai , Wang Jing , Chang Jiang 
Published: October 2020

AbstractThe Rho family of GTPases consists of 20 members including RhoE. Here, we discover the existence of a short isoform of RhoE designated as RhoEα, the first Rho GTPase isoform generated from alternative translation. Translation of this new isoform is initiated from an alternative start site downstream of and in-frame with the coding region of the canonical RhoE. RhoEα exhibits a similar subcellular distribution while its protein stability is higher than RhoE. RhoEα contains binding capability to RhoE effectors ROCK1, p190RhoGAP and Syx. The distinct transcriptomes of cells with the expression of RhoE and RhoEα, respectively, are demonstrated. The data propose distinctive and overlapping biological functions of RhoEα compared to RhoE. In conclusion, this study reveals a new Rho GTPase isoform generated from alternative translation. The discovery provides a new scope of understanding the versatile functions of small GTPases and underlines the complexity and diverse roles of small GTPases.
Pacific subsurface ocean temperature as a long-range predictor of South China tropical cyclone landfall
Authors: Sparks Nathan , Toumi Ralf 
Published: October 2020

AbstractSeasonal forecasts of the tropical cyclones which frequently make landfall along the densely populated South China coast are highly desirable. Here, we analyse observations of landfalling tropical cyclones in South China and of subsurface ocean temperatures in the Pacific warm pool region, and identify the possibility of forecasts of South China tropical cyclone landfall a year ahead. Specifically, we define a subsurface temperature index, subNiño4, and build a predictive model based on subNiño4 anomalies with a robust double cross-validated forecast skill against climatology of 23%, similar in skill to existing forecasts issued much later in the spring. We suggest that subNiño4 ocean temperatures precede the surface El Niño/Southern Oscillation state by about 12 months, and that the zonal shifts in atmospheric heating then change mid-level winds to steer tropical cyclones towards landfall in South China. We note that regional subsurface ocean temperature anomalies may permit atmospheric predictions in other locations at a longer range than is currently thought possible.
Prognostic performance of the FACED score and bronchiectasis severity index in bronchiectasis: a systematic review and meta-analysis
Authors: He Min , Zhu Min , Wang Chengdi , Wu Zuohong , Xiong Xiaofeng , Wu Hongxia , Cheng Deyun , Ji Yulin 
Published: October 2020

Abstract
Background: Bronchiectasis is a multidimensional lung disease characterized by bronchial dilation, chronic inflammation, and infection. The FACED (Forced expiratory volume in 1 s (FEV1), Age, Chronic colonization, Extension, and Dyspnea) score and Bronchiectasis Severity Index (BSI) are used to stratify disease risk and guide clinical practice. This meta-analysis aimed to quantify the accuracy of these two systems for predicting bronchiectasis outcomes.
Methods: PubMed, Embase, and the Cochrane Database of Systematic Reviews were searched for relevant studies. Quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) criteria. Pooled summary estimates, including sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. Summary receiver operating characteristic curves were constructed, and the area under the curve (AUC) was used to evaluate prognostic performance.
Results: We analyzed 17 unique cohorts (6525 participants) from ten studies. FACED scores with a cut-off value ≥ 5 predicted all-cause mortality better than BSI with a cut-off value ≥ 9, based on pooled sensitivity (0.34 vs 0.7), specificity (0.94 vs 0.66), PLR (4.76 vs 2.05), NLR (0.74 vs 0.48), DOR (6.67 vs 5.01), and AUC (0.87 vs 0.75). Both FACED scores with a cut-off value ≥ 5 (AUC = 0.82) and BSI scores with a cut-off value ≥ 5 or 9 (both AUC = 0.80) help to predict hospitalization.
Conclusions: At a cut-off value ≥ 5, FACED scores can reliably predict all-cause mortality and hospitalization, while BSI scores can reliably predict hospitalization with a cut-off of ≥5 or ≥9. Further studies are essential to validate the prognostic performance of these two scores.
Hybrid mapped optical‐OFDM using non‐linear companding technique for indoor visible light communication application
Authors: Sahoo Pritam Keshari , Prajapati Yogendra Kumar , Tripathi Rajeev 
Published: October 2020

In this study, the authors have developed an analytical model for reducing the peak‐to‐average‐power ratio (PAPR) using non‐linear companding transform (NCT) based on inverse hyperbolic sine function. As a consequence of non‐linear transform, this study compensates the system bit error rate (BER) degradation with the help of an error efficient hybrid modulation. By means of an inflexion point and companding parameter, more design flexibility is achieved; as a result, a trade‐off between PAPR and BER has reasonably been more precise. To the best of the authors’ awareness, no findings have yet been reported on the performance evaluation of the optical orthogonal frequency division multiplexing (OOFDM) system using a hybrid modulation technique. To find out the advantages of hybrid modulation with NCT, the authors inspect the nature of PAPR reduction, and BER improvement through numerical simulations. The numerical BER results exhibit roughly 3 dBm decay in the power efficiency of hybrid modulation with NCT over discrete Fourier transform (DFT) precoding technique. On the other hand, the NCT technique with hybrid modulation has 6 dB less PAPR than the DFT precoding technique.
Correlation scan matching algorithm based on multi‐resolution auxiliary historical point cloud and lidar simultaneous localisation and mapping positioning application
Authors: Liu Haiqiao , Luo Shibin , Lu Jiazhen 
Published: October 2020

The matching algorithm is an important part of simultaneous location and mapping. Aiming at the problem of large computation and poor real‐time performance of two‐dimensional lidar traditional correlation scan matching (CSM) algorithm, a multi‐resolution auxiliary historical point cloud matching algorithm is proposed, which combines high and low resolution and adopts a single‐frame to multi‐frame step‐by‐step matching scheme. The algorithm was carried out on the sweeping robot. Compared with the traditional CSM algorithm and iterative closest points algorithm, the single position accuracy of the method in this study is improved. In the indoor space of ∼10 m × 10 m, the cumulative error is reduced by 16.24 and 33.96%, respectively. Consequently, our algorithm can still manage to process in real‐time.
Gain‐enhancement technique for wearable patch antenna using grounded metamaterial
Authors: Das Goutam Kumar , Basu Subhadeep , Mandal Bappaditya , Mitra Debasis , Augustine Robin , Mitra Monojit 
Published: October 2020

In this study, a metamaterial (MTM)‐based high‐gain compact‐wearable antenna for 2.45 GHz industrial, scientific and medical radio band application has been proposed. To achieve the flexibility of the antenna, textile material felt fabric has been chosen as the substrate of the antenna as well as MTM. An omega (Ω) like structure has been taken as MTM unit cell design. High value of permeability is utilised for the gain enhancement of the antenna. In addition, very low specific absorption rate (SAR) is obtained using the MTM which makes the proposed antenna suitable for the biomedical application. The proposed antenna has achieved about 3 dB gain enhancement along with SAR value of 0.405 W/kg (1 g tissue). The design has been optimised and the prototype with the optimised parameter has been fabricated and tested over the semi‐solid phantom and human body. Further, the proposed antenna over different type of textile material has also been validated.