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HYPOTHESIS: Improving the processing efficiency of aerosol-coating technologies during mass production requires optimal nozzle spacing to allow complete surface coverage while at the same time not over-using the coating fluid. The difficult challenge is to estimate quantitatively the substrate coverage of fine droplets. Bouncing, splashing, and imbibition of droplets on solid surfaces have been widely explored, but little attention has been paid to liquid imbibition into woven textiles. EXPERIMENTS: Here, we experimentally and theoretically study the imbibition dynamics of aqueous droplets on woven cloths. The experimental process was observed using magnified visual observation. A proposed continuum mathematical model well predicts the aqueous imbibition fronts as a function of time. FINDINGS: A captivating four-petal imbibition spreading pattern is observed at enhanced magnification. The imbibition occurs separately in the megapores of the cloth between yarns, and in smaller minipores within individual yarn bundles. Surprisingly, weave intersections do not allow cross imbibition accentuating an anisotropic imbibition pattern. The proposed model achieves quantitative agreement with experiment. This is the first time that the mechanisms of four-petal droplet deposition, spreading, and imbibition into woven cloth have been outlined and successfully simulated. The mathematical model predicts advancement of liquids in anisotropic woven cloth, and permits evaluation of the coverages of droplet spreading.

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BACKGROUND: The widely spreading coronavirus disease (COVID-19) has three major spreading properties: pathogenic mutations, spatial, and temporal propagation patterns. We know the spread of the virus geographically and temporally in terms of statistics, i.e., the number of patients. However, we are yet to understand the spread at the level of individual patients. As of March 2021, COVID-19 is wide-spread all over the world with new genetic variants. One important question is to track the early spreading patterns of COVID-19 until the virus has got spread all over the world. RESULTS: In this work, we proposed AutoCoV, a deep learning method with multiple loss object, that can track the early spread of COVID-19 in terms of spatial and temporal patterns until the disease is fully spread over the world in July 2020. Performances in learning spatial or temporal patterns were measured with two clustering measures and one classification measure. For annotated SARS-CoV-2 sequences from the National Center for Biotechnology Information (NCBI), AutoCoV outperformed seven baseline methods in our experiments for learning either spatial or temporal patterns. For spatial patterns, AutoCoV had at least 1.7-fold higher clustering performances and an F1 score of 88.1%. For temporal patterns, AutoCoV had at least 1.6-fold higher clustering performances and an F1 score of 76.1%. Furthermore, AutoCoV demonstrated the robustness of the embedding space with an independent dataset, Global Initiative for Sharing All Influenza Data (GISAID). CONCLUSIONS: In summary, AutoCoV learns geographic and temporal spreading patterns successfully in experiments on NCBI and GISAID datasets and is the first of its kind that learns virus spreading patterns from the genome sequences, to the best of our knowledge. We expect that this type of embedding method will be helpful in characterizing fast-evolving pandemics.

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BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Spreading pattern and time interval of spreading are getting more and more attention. The aim of present study was to investigate spreading pattern in bulbar onset ALS patients and to explore the relationship between time interval of spreading and survival. METHODS: ALS patients with bulbar onset diagnosed at Chinese PLA General Hospital from January 2015 to December 2018 were recruited. Clinical features including gender, onset age, diagnostic delay, the second involved region (SIR), time of symptoms beyond the bulbar region, forced vital capacity (FVC), ALSFRS-R score, electromyography results, and survival time were retrospectively collected. RESULTS: A total of 96 bulbar onset ALS patients were collected. Overall patients showed female predominance. Median age at onset was 56 years. Median diagnostic delay was 8.5 months. Median time of symptoms beyond the bulbar region (TBBR) was 7 months. Median ALSFRS-R score at baseline was 40. Fifty-six (58.3%) patients' SIR were upper limb, 6 (6.3%) patients' SIR were lower limb, 3 (3.1%) patients' SIR were upper and lower limbs, and 5 (5.2%) patients' SIR were thoracic region. Twenty-six (27.1%) patients did not report SIR. The median survival time of patients with TBBR ≥ 7 months was significantly longer than that with TBBR < 7 month. Multivariate Cox regression showed that onset age and TBBR were prognostic factors. CONCLUSIONS: In bulbar onset ALS patients, cervical region is the second most common SIR. TBBR is an independent prognostic factor.

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Biofilms are bacterial communities in the shape of exopolysaccharide matrix-encased aggregates attached onto interphases able to resist environmental aggressions. The development of bacteria in the shape of biofilms deeply affects the performance of many industrial processes which work with fluidic systems, where bacteria may settle and prosper. As a consequence industrial equipment experiments low performance issues and substantial maintenance costs. The study of how bacteria of industrial interest such as Pseudomonas putida spread in these fluidic systems is highly dependent on the chosen experimental system to retrieve such data, thus using scaled prototypes becomes an essential step towards the design of a more efficient system to handle biofilms, either to control them or to prevent them. This protocol describes how to assemble, operate and maintain a device to grow and monitor the biofilm spreading pattern of this bacterium (as a function of the fluid hydrodynamics) in a custom-made chamber larger than those typically used in laboratory environments, and how to analyze the information gathered from it in a straightforward fashion. Description of the protocol was thought to be used as a working template not only for the presented case study but for any other potential experiment in different contexts and diverse scales following similar design principles.

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BACKGROUND: A large number (n = 460) of A(H7N9) human infections have been reported in China from March 2013 through December 2014, and H7N9 outbreaks in humans became an emerging issue for China health, which have caused numerous disease outbreaks in domestic poultry and wild bird populations, and threatened human health severely. The aims of this study were to investigate the directional trend of the epidemic and to identify the significant presence of spatial-temporal clustering of influenza A(H7N9) human cases between March 2013 and December 2014. METHODS: Three distinct epidemic phases of A(H7N9) human infections were identified in this study. In each phase, standard deviational ellipse analysis was conducted to examine the directional trend of disease spreading, and retrospective space-time permutation scan statistic was then used to identify the spatio-temporal cluster patterns of H7N9 outbreaks in humans. RESULTS: The ever-changing location and the increasing size of the three identified standard deviational ellipses showed that the epidemic moved from east to southeast coast, and hence to some central regions, with a future epidemiological trend of continue dispersing to more central regions of China, and a few new human cases might also appear in parts of the western China. Furthermore, A(H7N9) human infections were clustering in space and time in the first two phases with five significant spatio-temporal clusters (p < 0.05), but there was no significant cluster identified in phase III. CONCLUSIONS: There was a new epidemiologic pattern that the decrease in significant spatio-temporal cluster of A(H7N9) human infections was accompanied with an obvious spatial expansion of the outbreaks during the study period, and identification of the spatio-temporal patterns of the epidemic can provide valuable insights for better understanding the spreading dynamics of the disease in China.

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OBJECTIVE: Although surgery in selected small-cell lung cancer (SCLC) patients has been proposed as a part of multimodality therapy, so far, the prognostic impact of node-spreading pattern has not been fully elucidated. To investigate this issue, a retrospective analysis was performed. METHODS: From 01/1996 to 12/2012, clinico-pathological, surgical, and oncological features were retrospectively reviewed in a multicentric cohort of 154 surgically treated SCLC patients. A multivariate Cox proportional hazard model was developed using stepwise regression, in order to identify independent outcome predictors. Overall (OS), cancer-specific (CSS), and Relapse-free survival (RFS) were calculated by Kaplan-Meier method. RESULTS: Overall, median OS, CSS, and RFS were 29 (95 % CI 18-39), 48 (95 % CI 19-78), and 22 (95 % CI 17-27) months, respectively. Lymphadenectomy was performed in 140 (90.9 %) patients (median number of harvested nodes: 11.5). Sixty-seven (47.9 %) pN0-cases experienced the best long-term survival (CSS: 71, RFS: 62 months; p < 0.0001). Among node-positive patients, no prognostic differences were found between pN1 and pN2 involvement (CSS: 22 vs. 15, and RFS: 14 vs. 10 months, respectively; p = 0.99). By splitting node-positive SCLC according to concurrent N1-invasion, N0N2-patients showed a worse CSS compared to those cases with combined N1N2-involvement (N0N2: 8 months vs. N1N2: 22 months; p = 0.04). On the other hand, the number of metastatic stations (p = 0.80) and the specific node-level (p = 0.85) did not affect CSS. At multivariate analysis, pN+ (HR: 3.05, 95 % CI 1.21-7.67, p = 0.02) and ratio between metastatic and resected lymph-nodes (RL, HR: 1.02, 95 % CI 1.00-1.04, p = 0.03) were independent predictors of CSS. Moreover, node-positive patients (HR: 3.60, 95 % CI 1.95-6.63, p < 0.0001) with tumor size ≥5 cm (HR: 1.85, 95 % CI 0.88-3.88, p = 0.10) experienced a worse RFS. CONCLUSIONS: In selected surgically treated SCLC, the long-term survival may be stratified according to the node-spreading pattern.

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OBJECTIVE: Ultrasound-guided cervical nerve root block (US-CRB) is considered a safe and effective method for the treatment of radicular pain. However, previous studies on the spreading pattern of injected solution in US-CRB have reported conflicting results. The aim of this study was to investigate the spreading pattern in relation to injection volume. DESIGN: An institutional, prospective case series. SETTING: A university hospital. SUBJECTS: Fifty-three patients diagnosed with mono-radiculopathy in C5, 6, or 7. METHODS: US-CRB with fluoroscopic confirmation was performed. After the cervical roots were identified in ultrasound imaging, a needle was gently introduced toward the posterior edge of the root using an in-plane approach. The spread of 1 mL and 4 mL contrast medium, each injected in the same needle position, was examined with anteroposterior and lateral fluoroscopic views. After contrast injection, a mixture of local anesthetic and corticosteroid was injected. Clinical outcome was assessed using a numeric rating scale before and 2 weeks after the procedure. RESULTS: Contrast medium did not spread into the epidural space in any patients with 1 mL contrast medium injection, but it did spread into the intraforaminal epidural space in 13 patients (24.5%) with 4 mL. Pain improved in all patients. There was no significant difference in pain relief according to the spreading pattern. CONCLUSION: The spreading pattern of injected solution in US-CRB could be partially affected by the injectant volume. However, further studies are needed to assess the importance of other factors, such as needle position and physiological effects.

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OBJECTIVE: Gradient magnetic field topography (GMFT) with magnetoencephalography (MEG) has been developed to demonstrate magnetic-field gradients of epileptic spikes on a volume-rendered brain surface. We evaluated GMFT in patients with anterior 2/3 corpus callosotomy (ACC) for drop-attacks. METHODS: Eight patients (age; 11-37 years) underwent ACC. GMFT evaluated the predominant distributions (anterior/posterior) and the spreading patterns (unilateral/bilateral) of pre- and postoperative interictal MEG spikes corresponding to generalized spikes on EEG. We compared the occurrence of four types of spikes; anterior unilateral spike (AUS), posterior unilateral spike (PUS), anterior bilateral spike (ABS), posterior bilateral spike (PBS) between 5 patients (group G) with good control of drop attacks and 3 patients (group P) with residual drop attacks. RESULTS: Preoperatively, GMFT showed the proportion of ABS in group G (mean ± SD, 57.4 ± 9.7%) was significantly (p=0.024) higher than that in group P (31.6 ± 15.2%). The number and proportion of postoperative ABS and PBS in group G were significantly decreased (p<0.05 in all). CONCLUSION: GMFT is valuable to evaluate pre- and post-operative predominant spikes in patients with drop attacks. SIGNIFICANCE: GMFT revealed a higher proportion of preoperative ABS and postoperative decline of both ABS and PBS in patients with good control of drop attacks after ACC.

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Objective To evaluate the disease onset regions and spreading patterns in sporadic amyotrophic lateral sclerosis (ALS)patients and related influencing factors.Methods We performed a prospective analysis of 1 58 ALS patients.The disease-onset was confirmed according to the patients’self-reports,neurological examination results and electromyogram study.We followed up 1 5 1 patients with the second or other affected body regions during the disease progression.Data were analyzed according to the different groups of onset regions.Results 1.In 94.3% (149/1 58)of the patients,the early motor manifestations were focally in the bulbar,upper or lower limbs.2.The region of onset was associated with signs of lower motor neuron (LMN)and upper motor neuron (UMN)involvement (P = 0.000 ).The LMN involvement was more distinctive in patients with bulbar onset (65.4%,1 7/26 )group.Patients with cervical onset more frequently showed pure LMN (47.9%,45/94 )or concomitant UMN (52.1%,49/94)signs in the affected limbs.The highest proportion of UMN and LMN signs in the affected lower limb was found in the lumbar onset (83.8%,31/37 )group.3.Spreading patterns:Rostral to caudal spreading pattern was more frequent in bulbar onset patients.For patients with limb onset,there were significant differences between spreading patterns and disease-onset regions (P =0.04).Circular (31.5%,28/89),horizontal (30.3%,31/89)and vertical (21.3%,1 9/89)spreading patterns were more frequent in cervical onset patients whereas circular (47.2%,1 7/36)spreading patterns were more frequent in lumbar onset patients.4.There was a strong association between the rate of progression and age of disease onset (P =0.01 1).Patients aged over 60 had a faster progression.Conclusion ALS is a focal process at motor axis along the spinal cord and cerebral cortex.Different disease-onset can cause different distribution of UMN and LMN signs.Therefore,special attention should be paid to the signs of disease-onset clinically.ALS does start focally and spreads to adjacent regions.Elder patients have a faster disease progression.

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BACKGROUND: Foramen ovale electrode(FOE) was introduced for the lateralizing purposes of mesio-temporal lobe(MTL) seizures which were often not clearly identified by extracranial EEGs. An analysis of interictal and ictal EEG features recorded from FOE was conducted to evaluate its clinical usefulness. METHODS: A multipolar, three-contact FOE was implanted bilaterally in 16 intractable epileptic patients for the lateralizing purposes of a MTL onset of seizures due to the evidence of bilateralities recorded from extracranial EEGs. A detailed analysis of the electrical pattern and temporal relationships in 16 patients was conducted. RESULTS: After a long-term telemetry recording with FOE, all patients revealed a clear onset of seizures originating from one or both sides of the MTL and underwent ATL. The lateralization of interictal epileptiform discharges (IEDs) in scalp EEG and FOE were concordant with the operation sites in 12 patients and 8 patients respectively. Among various configurations of IEDs recorded from FOE, periodic spikes or sharp waves with/without fast activities were dominant features in the operation site, but polyspikes, isolated spikes or sharp waves, and positive spikes were more common in the non-operation site. Five patients showed ictal onset discharges concordant with the operation site in the scalp EEG, but 10 patients in FOE. Rhythmic fast beta, alpha frequency activity, repetitive spikes or sharp waves prevailed over other FOE seizure onset patterns in the operation site, but delta and theta slowing, positive spikes prevailed in the non-operation site. A "start-stop-start" pattern was 100% concordant with the operation site. The time interval between bilateral FOE recorded ictal onset was 16.53 sec when the ictal discharge started from the operation site and 7.92 sec when started from the non-operation site. The time interval between FOE and scalp EEG ictal onset was 22.82 sec in the operation site and 8.61 sec in the non-operation site. Among various spreading patterns of ictal epileptiform discharge, FOE contralateral FOE ipsilateral temporal lobe, or contralateral temporal lobe was the most common feature(47.71%). No serious complications resulted from implantation of FOE in this series. CONCLUSIONS: Our results indicated that FOE was very useful in confirming the laterality of MTL. The configurations of IEDs and ictal discharges recorded from FOE were also useful for further determination of lateralization. The "start-stop-start" pattern of ictal discharges was especially a quite reliable marker, which should be cautiously detected during the analysis of ictal events. FOE could also provide useful information about the spreading patterns of ictal discharges.

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