Patient-Specific Robot-Assisted Stroke Rehabilitation Guided by EEG - A Feasibility Study

Multi-session robot-assisted stroke rehabilitation program requires patients to perform repetitive tasks. It is challenging for the patient to maintain concentration during training sessions. A novel intervention strategy using Electroencephalography (EEG) signals is proposed to maintain concentration during training by enhancing the engagement of stroke patients using robot-assisted multi-session rehabilitation. The approach is illustrated by applying it to one stroke patient undergoing 12 training sessions of hand motor training on the AMADEO rehabilitation device. AMADEO offers four modes of training programs of increased intensity comprising passive training, passive training with biofeedback, assistive training as well as active 2D training games. The EEG signals are measured over eight electrode sites: FC4, C4, CP4, FC3, C3, CP3, Cz, and CPz during each training day to extract movement-related cortical potential (MRCP) signals. Moreover, functional hand recovery parameters are determined using the AMADEO assessment tool. The patient's level of engagement is determined by the negative amplitude of the MRCP signal. The rehabilitation program is switched to a more intense training mode when a consistent decrease is observed in the negative amplitude of MRCP signals from the monitored electrodes. Using this approach, the rehabilitation program becomes patient-specific and adaptive. In addition, it is shown that each training mode exhibits a different recovery level of the affected hand and maximum recovery is achieved when MRCP signals indicate that the patient is actively participating in the training.

[The fundus autofluorescence of retinal astrocytic hamartomas in tuberous sclerosis complex]

Objective: To investigate the autofluorescence findings of retinal astrocytic hamartoma (RAH) in patients with tuberous sclerosis complex (TSC). Methods: It was a retrospective case series study. Twenty-three patients (35 eyes) who were referred to Department of Internal Medicine and Department of Ophthalmology, Peking Union Medical College Hospital between November 2012 and June 2018 with established TSC-associated RAH diagnosis were included. The findings of fundus autofluorescence, fundus photos and spectral-domain optical coherence tomography (SD-OCT) were retrospectively reviewed. RAH lesions were classified into three types based on the morphology shown in fundus photos. The fundus autofluorescence features of TSC-associated RAH were described. The Welch's test and Fisher's exact test were used for statistical analysis. Results: The patients were 8 males and 15 females aged (28±9) years old (range, 15-55 years). Seventy-two RAH lesions were examined, including 59 type 1 RAHs, 7 type 2 RAHs and 6 type 3 RAHs. According to fundus autofluorescence, type 1 RAHs could be further divided into reduced, speckled and background autofluorescence patterns, among which the hypoautofluorescence pattern accounted for the majority (69.5%, 41/59), while the speckled pattern was usually accompanied by outer retinal disorganization and discontinuation of photoreceptor outer segment as revealed by SD-OCT. No significant difference was revealed in tumor thickness for reduced, speckled and background autofluorescence patterns of type 1 RAHs [(490.2±97.9) vs. (589.2±221.6) vs. (463.0±76.2) μm respectively, F=1.426, P=0.283]. Among type 1 RAHs, the number of reduced autofluorescence pattern lesions found in perifoveal, peripapillary, inferonasal, inferotemporal, superonasal, superotemporal quadrants were 9, 4, 4, 7, 4, 13 respectively, while that of speckled autofluorescence pattern lesions were 3, 0, 3, 2, 3, 2 and background autoflurorescence pattern lesions 3, 0, 1, 1, 0, 0. No significant difference was revealed in location distribution (P=0.452) either. Type 2 RAHs featured numerous hyperautofluorescent spots or plaques, and calcification in type 2 RAHs varied in autofluorescence intensity. Type 3 RAHs, combining the features of type 1 and 2 RAHs, were characterized by central hyperautofluorescent spots and hypoautoflurescent rim, but the area of hyperautofluorescence was smaller than that of calcification as shown in fundus photos. Conclusions: In TSC, the fundus autofluorescence of RAHs varies from hypoautofluorescence to hyperautofluorescence patterns according to RAH types. The retinal involvement and calcification degree of TSC-associated RAHs could be reflected on the autofluorescence, which was beneficial to the full assessment. (Chin J Ophthalmol, 2020, 56: 211-216).

Correlation between the hemoporfin-mediated photodynamic treatment response and the dermoscopy vascular pattern in patients with a port-wine stain: a prospective study

BACKGROUND

Vascular targeted photodynamic therapy (PDT) is a novel and promising therapy for the treatment of port-wine stains (PWS). There has been little prior exploration to our knowledge of how the dermatological vascular pattern may predict the response to PDT.

OBJECTIVES

To analyse whether the vascular pattern classifications of PWS by dermoscopy can predict the efficacy of PDT.

METHODS

This prospective cohort study included 163 patients with a clinical diagnosis of PWS who were treated twice with hemoporfin-mediated photodynamic therapy (HMME-PDT) at two-month intervals and followed up for 6 months. The vascular manifestations of dermoscopy with PWS were independently classified into 8 categories by 3 dermatologists. Images of the lesions were taken using VISIA, and the vascular patterns were imaged by dermoscopy by the same investigator. Images were captured before and after each treatment. The efficacy was evaluated with pre- and post-treatment VISIA images, and correlations between efficacy and vascular patterns were analysed by four dermatologists in a blinded and independent manner, between 10 January 2019 and 11 December 2019.

RESULTS

In the dermoscopy images for the whole cohort, dotted and globular vessels (15.3%), short clubbed vessels (18.4%) and curved vessels (12.9%) were highly associated with cure and beneficial treatment effects. Pale halos surrounding brown dots (8.0%) and arborizing vessels (9.8%) were mainly correlated with skin lesion alleviation. Mixed vessels (12.9%), a grey-whitish veil (11.7%) and reticular patterns (11.0%) were mainly associated with no effect. The differences between each subgroup were statistically significant (P = 0.000).

CONCLUSIONS

There is a clear correlation between the efficacy of PDT and the dermoscopy pattern in patients with PWS. Dermoscopy may therefore provide very useful clinical information prior to treatment in these cases. In addition, the vascular manifestations of PWS determined by dermoscopy help to predict response to PDT and manage patient expectations.

Knockdown of GmVQ58 encoding a VQ motif-containing protein enhances soybean resistance to the common cutworm (Spodoptera litura Fabricius)

Plants have evolved complex defense mechanisms to withstand insect attack. Identification of plant endogenous insect resistance genes is of great significance for understanding plant-herbivore interactions and improving crop insect resistance. Soybean (Glycine max (L.) Merr.) is an important crop that is often attacked by the common cutworm (CCW) (Spodoptera litura Fabricius). In this study, based on our transcriptomic data, the gene GmVQ58, encoding a FxxxVQxxTG (VQ) motif-containing protein, was cloned and characterized. This gene showed the highest expression in the leaves and roots and was up-regulated significantly after CCW attack. Constitutive expression of GmVQ58 rescued the susceptibility of an Arabidopsis mutant to CCW, and interference of GmVQ58 in soybean hairy roots enhanced the resistance to CCW. Furthermore, GmVQ58 was localized to the nucleus and physically interacted with the transcription factor GmWRKY32. The expression of two defense-related genes, GmN:IFR and GmVSPβ, was up-regulated in GmVQ58-RNAi lines. Additionally, the promoter region of GmVQ58 was likely selected during domestication, resulting in different expression patterns in cultivated soybeans relative to wild soybeans. These results suggest that silencing GmVQ58 confers soybean resistance to CCW.

Effects of Diutina rugosa SD-17 on growth performance, intestine morphology, and immune status of chickens

Probiotics are considered the preferred alternatives to antibiotics for growth promotion and disease prevention. Previous studies have confirmed that Diutina rugosa SD-17 has the potential as a probiotic. We evaluated the probiotic effect of D. rugosa SD-17 on 360 one-day-old Hy-line brown chickens that were divided into 2 groups, and each group contained 6 replicate pens with 30 birds per pen. The chickens were fed with basal diet supplemented with or without D. rugosa SD-17, and the effects of D. rugosa SD-17 on growth performance, intestine morphology, and immune status were assessed. Body weight was significantly improved from week 3 to 6 (P < 0.05), and the feed conversion ratio was significantly improved in weeks 1 and 2 (P < 0.001). The length of the duodenum was lengthened significantly in week 3 (P < 0.05), and supplementation of D. rugosa SD-17 significantly increased villus height and villus height to crypt depth ratio in the ileum in week 3 (P < 0.05). Expressions of tight-junction-related genes of zonula occludens-2 and occludin in the ileum were significantly increased (P < 0.05). The proliferation capacity of blood lymphocytes stimulated by concanavalin A was significantly enhanced (P < 0.05), and the proportion of helper T (Th) cells increased significantly (P < 0.05). Expressions of Th1 cell markers IL-2 and interferon (IFN)-γ and immune-related genes of IL-1β, transforming growth factor-β, and IFN-γ in ileum were significantly increased (P < 0.05). These results indicated that D. rugosa SD-17 improved the growth and regulated immunity of chickens, and could be optimized for use as a feed additive for livestock and poultry.

Swelling of Doubly Magic ^{48}Ca Core in Ca Isotopes beyond N=28

Interaction cross sections for ^{42-51}Ca on a carbon target at 280  MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

Supplementation of Inulin with Various Degree of Polymerization Ameliorates Liver Injury and Gut Microbiota Dysbiosis in High Fat-Fed Obese Mice

The chain length of fructan determines its different physiological effects. This study is to explore the effects of low-performance inulin [LPI, degree of polymerization (DP) ≤ 9] and high-performance inulin (HPI, DP ≥ 23) on obesity-associated liver injury of high-fat diet (HFD) feeding mice and its underlying mechanism. Eight weeks of supplementation of C57BL/6J mice with HPI, relative to LPI (p < 0.05), caused the more efficient improvement against the HFD-induced liver insulin resistance through activating IRS1/PI3K/Akt pathway and reduced protein expressions of inflammatory factors nuclear factor-kappaB (NF-κB) and interleukin-6 (IL-6) in the liver. HPI exhibited the more positive effects on liver steatosis by inhibiting acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and sterol regulatory element binding protein 1 (SREBP1) in comparison with LPI (p < 0.05). HPI also increased acetic acid, propionic acid, and butyric acid levels in the colon of HFD-fed mice (p < 0.05). Compared to LPI, HPI feeding of HFD-fed mice led to the more effective decrease in the Firmicutes abundance from 72.1% to 34.5%, but a more significant increase in the Bacteroidetes population from 19.8 to 57.1% at the phyla level, and increased the abundance of Barnesiella, Bacteroides, and Parabacteroides at the genus level (p < 0.05). Depending on DP, HPI exerts the more positive regulation on liver injury and gut microbiota dysfunction than LPI.

Nonconservative Coupling in a Passive Silicon Microring Resonator

The authors report on nonconservative coupling in a passive silicon microring between its clockwise and counterclockwise resonance modes. The coupling coefficient is adjustable using a thermo-optic phase shifter. The resulting resonance of the supermodes due to nonconservative coupling is predicted in theory and demonstrated in experiments. This Letter paves the way for fundamental studies of on-chip lasers and quantum photonics, and their potential applications.

P6231Iron status and risk of cardio-metabolic diseases in European adults: a Mendelian randomization study

Background

Observational studies have reported conflicting results about the associations of iron status with risk of cardio-metabolic diseases but such studies are constrained by confounding and reverse causality.

Purpose

To assess the causal relevance of iron status biomarkers (transferrin, serum iron, and ferritin) for risk of coronary artery diseases (CAD), ischaemic stroke (IS), and type 2 diabetes (T2D), using Mendelian randomization (MR).

Methods

Effect size estimates for genetic variants associated with iron status biomarkers were obtained from the Genetics of Iron Status consortium (transferrin saturation, serum iron, and ferritin: n=48,972). The corresponding effects of these variants on the risk of CAD, IS and T2D were obtained from a meta-analysis of unrelated participants of European ancestry in the UK Biobank (UKB), together with previously recruited participants in CARDIOGRAMplusC4D (total n=90,377 CAD cases), MEGASTROKE (total n=43,381 IS cases) and DIAGRAM (total n=74,124 T2D cases), respectively. The main analysis used a two-sample inverse-variance weighted MR, while the sensitivity analyses used weighted-median, weighted-mode, MR-PRESSO, and MR-Egger approaches.

Results

MR analysis demonstrated significant inverse association of each of the three genetically-instrumented iron status biomarker with risk of CAD (transferrin saturation OR=0.96 [95% CI: 0.92–0.99], p=0.02; serum iron OR=0.93 [0.89–0.97], p=0.001; and ferritin OR=0.86 (0.79–0.94), p=0.001, per 1 SD higher level). In contrast, these iron status biomarkers showed positive associations with risk of T2D (transferrin saturation OR=1.06 [1.01–1.11], p=0.01; serum iron OR=1.06 [0.99–1.13], p=0.07; and ferritin OR=1.12 [0.99–1.26], p=0.06, per 1 SD higher level). There was positive, but non-significant, association of IS with each of the iron status biomarker analysed. Sensitivity analyses using several different MR approaches yielded concordant results.

Conclusions

Among European adults, iron status appeared to have causal associations, but in opposite directions, with the risk of CHD and T2D. Our findings highlight the need for caution about strategies for advocating iron supplementation in individuals with normal haemoglobin levels for prevention of CAD.

Acknowledgement/Funding

British Heart Found, Medical Research Council, Wellcome Trust, NIHR Biomedical Research Centre, Oxford

Output feedback H∞ control for active suspension of in-wheel motor driven electric vehicle with control faults and input delay

In this paper, an output feedback H_∞ controller is proposed for active suspension of an electric vehicle driven by in-wheel motors with actuator faults and time delay. The dynamic damping in-wheel motor driven system, in which the in-wheel motor is designed as a dynamic vibration absorber (DVA), is developed to improve ride quality and isolate the force transmitted to motor bearings. Furthermore, parameters of vehicle suspension and DVA are optimized based on the particle swarm optimization (PSO) to achieve better suspension performance. As some of the states such as the DVA velocity and unsprung mass velocity are difficult to measure, a robust H_∞ output feedback controller is developed to deal with the problem of active suspension control with actuator faults and time delay. The proposed controller could guarantee the system's asymptotic stability and H_∞ performance, simultaneously satisfying the performance constraints such as road holding, suspension stroke, and actuator limitation. Finally, the effectiveness of the proposed output feedback controllers is demonstrated based on the quarter vehicle suspension model under bump and random road excitations.

[Relationship between cervical lesions and the type-specific viral load of high risk HPV reflected by the Ct value of Cobas 4800 HPV system]

Objective: To explore the relationship between cervical lesions and high risk HPV (HR-HPV) viral load reflected by the cycle threshold (Ct) values of Cobas 4800 HPV (Cobas 4800) system. Methods: From August 2016 to September 2017, 7 000 women from Shenzhen, were recruited for cervical cancer screening with Cobas 4800 system and cytology co-test. Colposcope biopsies were performed on women who were positive of HPV 16, 18, and positive of HPV types other than 16,18 with cytology [≥ atypical squamous cell of undetermined signification (ASCUS)], or HPV negative but abnormal of cytology [≥ low grade squamous intraepithelial lesion (LSIL)]. The Ct values of HPV 16, 18 and all combined other types coming from Cobas 4800 system were used as an indicator of viral load to analyze the relationship between type-specific HPV load and the cervical lesions. Results: (1) Among the 7 000 screening women, 370 cases were positive for cervical cancer screening, 325 of them underwent colposcope biopsies, and coloposcopy referred rate was 87.8% (325/370). Among 325 women undergoing cervical biopsy, pathological diagnosis was 119 cases of normal cervical cervix, 151 cases of LSIL, and 55 cases of high-grade squamous intraepithelial lesion (HSIL) and above (HSIL(+); including 53 cases of HSIL, 1 case of cervical adenocarcinoma, and 1 case of cervical squamous cell carcinoma). (2) The Ct value of HPV 16 was inversely correlated with the upgrading of the lesions (r=-0.617, P=0.000), and significant different among normal cervix,LSIL and HSIL(+) (35.4±4.5 vs 31.0±6.0 vs 26.5±4.0; F=25.537, P=0.000). There was no correlation between Ct value of HPV 18 and cervical lesions (r=-0.021, P=0.902). The Ct value of other 12 HPV types was statistically difference among normal normal cervix, HSIL(+) and cervicitis (33.0±5.3 vs 29.9±7.2 vs 29.8±5.8; F=5.087, P=0.007). Among them, LSIL and HSIL(+) were significantly lower than normal cervix (P<0.05), but there was no significant difference between LSIL and HSIL(+) (P>0.05). Conclusion: The Ct value of HPV 16 detecting in Cobas 4800 system as an indicator of virus load obviously correlates with different grades of cervical lesions, therefore could be a reference of cervical lesion existence and an indicator of lesion prognosis.

[Value of the BioPerfectus multiplex real time HPV assay for self-collected samples cervical cancer screening]

Objective: To evaluate the feasibility of the BioPerfectus multiplex real time (BMRT) HPV assay for self-sample cervical cancer screening. Methods: Eight hundreds and thirty-nine self-collected and physician-obtained DNA samples from the Shenzhen cervical cancer screening trial Ⅳ(SHENCCAST-Ⅳ) study collected samples for cervical cancer screening during June 2013 to September 2014 were detected by BMRT HPV assay to evaluate the screening efficacy. Results: A total of the 839 women who were screened, 804 with complete BMRT HPV data was included in the study, and average age was (46±7) years. Of the 804 women, the positive rates of 14 high-risk HPV genotypes (including HPV 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66 subtype) of self-sample and physician-obtained samples were 12.2% (98/804) and 12.8% (103/804), respectively (χ(2)=0.14, P=0.71). Self-collected samples with HPV-positive had significantly more cells (median 19 901.0) than physician-obtained samples (median 1 778.4), and there was statistically significant difference (Z=-7.61, P<0.01). The degree of agreement between self-sample and physician-obtained samples of HPV 16, HPV 18 and other 12 high risk HPV genotype was 99.8%, 100.0% and 96.1%, respectively. And the consistent Kappa value was 0.95, 1.00 and 0.81, respectively. Of 804 samples, there were 6 cervical intraepithelial neoplasia (CIN)Ⅱ(+) cases. There were no missed CINⅡ(+) cases by BMRT HPV assay. Conclusion: BMRT HPV assay is feasible for self-sample cervical cancer screening.

RNA-Seq analysis reveals transcript diversity and active genes after common cutworm (Spodoptera litura Fabricius) attack in resistant and susceptible wild soybean lines

BACKGROUND

Common cutworm (CCW) is highly responsible for destabilizing soybean productivity. Wild soybean is a resource used by breeders to discover elite defensive genes.

RESULTS

The transcriptomes of two wild accessions (W11 and W99) with different resistance to CCW were analyzed at early- and late-induction time points. After induction, the susceptible accession W11 differentially expressed 1268 and 508 genes at the early and late time points, respectively. Compared with W11, the resistant accession W99 differentially expressed 1270 genes at the early time point and many more genes (2308) at the late time point. In total, 3836 non-redundant genes were identified in both lines. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that the differentially expressed genes (DEGs) in W99 at the late time point were mostly associated with specific processes and pathways. Among the non-redundant genes, 146 genes were commonly up-regulated in the treatment condition compared with the control condition at the early- and late-induction time points in both accessions used in this experiment. Approximately 40% of the common DEGs were related to secondary metabolism, disease resistance, and signal transduction based on their putative function. Excluding the common DEGs, W99 expressed more unique DEGs than W11. Further analysis of the 3836 DEGs revealed that the induction of CCW not only up-regulated defense-related genes, including 37 jasmonic acid (JA)-related genes, 171 plant-pathogen-related genes, and 17 genes encoding protease inhibitors, but also down-regulated growth-related genes, including 35 photosynthesis-related genes, 48 nutrition metabolism genes, and 28 auxin metabolism genes. Therefore, representative defense-related and growth-related genes were chosen for binding site prediction via co-expression of transcription factors (TFs) and spatial expression pattern analyses. In total, 53 binding sites of 28 TFs were identified based on 3 defense-related genes and 3 growth-related genes. Phosphate transporter PT1, which is a representative growth-related gene, was transformed into soybean, and the transgenic soybean plants were susceptible to CCW.

CONCLUSIONS

In summary, we described transcriptome reprograming after herbivore induction in wild soybean, identified the susceptibility of growth-related genes, and provided new resources for the breeding of herbivore-resistant cultivated soybeans.

Liquid metal-filled magnetorheological elastomer with positive piezoconductivity

Conductive elastic composites have been used widely in soft electronics and soft robotics. These composites are typically a mixture of conductive fillers within elastomeric substrates. They can sense strain via changes in resistance resulting from separation of the fillers during elongation. Thus, most elastic composites exhibit a negative piezoconductive effect, i.e. the conductivity decreases under tensile strain. This property is undesirable for stretchable conductors since such composites may become less conductive during deformation. Here, we report a liquid metal-filled magnetorheological elastomer comprising a hybrid of fillers of liquid metal microdroplets and metallic magnetic microparticles. The composite’s resistivity reaches a maximum value in the relaxed state and drops drastically under any deformation, indicating that the composite exhibits an unconventional positive piezoconductive effect. We further investigate the magnetic field-responsive thermal properties of the composite and demonstrate several proof-of-concept applications. This composite has prospective applications in sensors, stretchable conductors, and responsive thermal interfaces.

Liquid metal-filled elastic composites for strain sensing devices exhibit reduced conductivity under strain, which limits their usefulness. Here, the authors report a positive piezoconductive effect in liquid metal-filled magnetorheological elastomers and illustrate proof-of concept applications.

Fu Brick Tea Alleviates Chronic Kidney Disease of Rats with High Fat Diet Consumption through Attenuating Insulin Resistance in Skeletal Muscle

Fu brick tea is a unique post-fermented dark tea product which undergoes controlled fermentation by "golden flower" fungus Eurotium cristatum. This study examined the effects of Fu brick tea aqueous extract (FTE) to alleviate insulin resistance, chronic kidney disease (CKD), and its regulatory mechanism in high fat diet (HFD)-induced obese rats. Sixteen-week administration of FTE at 400 mg/kg bw in rats significantly antagonized HFD-induced insulin resistance and CKD with elevations in serum leptin, TC, TG, LDL-C, blood urea nitrogen, uric acid, and creatinine levels, respectively ( p < 0.05). FTE treatment decreased the glomerular area, the thickness of basement membrane of renal tubules, and kidney fibrosis in HFD-fed rats. FTE alleviated insulin resistance through down-regulation of SIRP-α expression and activation of the insulin signaling Akt/GLUT4, FoxO1, and mTOR/S6K1 pathways in skeletal muscle. Furthermore, FTE prevented the HFD-caused kidney dysfunction and lipid or collagen accumulation, which was accompanied by the inhibition of GSK-3β phosphorylation and the action of PI3K/Akt and nuclear accumulation of Nrf2 in kidney. These results indicated that FTE alleviated insulin resistance and CKD through modulating insulin signal transduction cascades in skeletal muscle and enhanced the Nrf2 expression in kidney.

Ultra-sharp asymmetric Fano-like resonance spectrum on Si photonic platform

In this paper, we report the generation of an ultra-sharp asymmetric resonance spectrum through Fano-like interference. This generation is accomplished by weakly coupling a high-quality factor (Q factor) Fabry-Pérot (FP) cavity and a low-Q factor FP cavity through evanescent waves. The high-Q FP cavity is formed by Sagnac loop mirrors, whilst the low-Q one is built by partially transmitting Sagnac loop reflectors. The working principle has been analytically established and numerically modelled by using temporal coupled-mode-theory (CMT), and verified using a prototype device fabricated on the 340 nm silicon-on-insulator (SOI) platform, patterned by deep ultraviolet (DUV) lithography. Pronounced asymmetric resonances with slopes up to 0.77 dB/pm have been successfully measured, which, to the best of our knowledge, is higher than the results reported in state-of-the-art devices in on-chip integrated Si photonic studies. The established theoretical analysis method can provide excellent design guidelines for devices with Fano-like resonances. The design principle can be applied to ultra-sensitive sensing, ultra-high extinction ratio switching, and more applications.