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1.
BMC Musculoskelet Disord ; 22(1): 345, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33845826

RESUMO

BACKGROUND: In the late stage of spinal tuberculosis, the bony destruction and vertebral collapse often leads to significant kyphosis, presenting clinically as a painful gibbus deformity, with increased instability, vertebral body translations and increased risk of neurologic involvement. Spinal osteotomy is thought to be suitable for most patients with severe rigid kyphosis. The aim of this study was to evaluate the efficacy of transpedicular bi-vertebrae osteotomy technique in the patients with Pott's kyphosis and other post-tubercular spinal deformity. METHODS: Between January 2012 and December 2015, 18 patients with post-tubercular spinal deformity underwent the transpedicular bi-vertebrae wedge osteotomy, with a minimum follow up of 27.0 months. Preoperative and postoperative kyphotic angle, sagittal plane parameters (TK for thoracic deformity, TLK for thoracolumbar and LL for lumbar deformity) and sagittal vertical axis (SVA) were measured. Oswestry Disability Index (ODI), Visual analog scale (VAS) and modified American Spinal Injury Association grading (ASIA) of preoperative and final follow-up were documented and compared. RESULTS: The average operation time was 305 minutes (range, 200-430 minutes) with a mean intraoperative blood loss of 425 mL (range, 200-700 mL). The kyphotic angles decreased from 80.3° (range, 28.5°-130.8°) preoperatively to 26.1° (range, 7.0°-63.3°) at the final follow-up (P<0.01). The mean VAS score was reduced from preoperative 5.2(range, 2-9) to 0.9(range, 0-2, P<0.01) and the ODI improved from 55.3% (range, 46%-76%) to 6.3% (range, 2%-18%, P<0.01). At final follow-up, there was radiographic evidence of solid fusion at the osteotomy site and fixed segments in all patients. Neurological function improved from ASIA scale D to E in 7 patients, C to D in 3 patients. CONCLUSIONS: Our results suggest that transpedicular bi-vertebrae wedge osteotomy is a safe and effective treatment option for post-tubercular spinal deformity. This technique achieves satisfying correction and fusion rates with adequate decompression of neurological elements.

2.
Brain ; 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33742668

RESUMO

The aging brain is vulnerable to a wide array of neuropathologies. Prior work estimated that the three most studied of these, Alzheimer's disease (AD), infarcts, and Lewy bodies, account for about 40% of the variation in late life cognitive decline. However, that estimate did not incorporate many other diseases that are now recognized as potent drivers of cognitive decline (e.g. limbic predominant age-related TDP-43 encephalopathy [LATE-NC], hippocampal sclerosis, other cerebrovascular conditions). We examined the degree to which person-specific cognitive decline in old age is driven by a wide array of neuropathologies. 1,164 deceased participants from two longitudinal clinical-pathologic studies, the Rush Memory and Aging Project and Religious Orders Study, completed up to 24 annual evaluations including 17 cognitive performance tests and underwent brain autopsy. Neuropathologic examinations provided 11 pathologic indices, including markers of AD, non-AD neurodegenerative diseases (i.e. LATE-NC, hippocampal sclerosis, Lewy bodies), and cerebrovascular conditions (i.e. macroscopic infarcts, microinfarcts, cerebral amyloid angiopathy, atherosclerosis, and arteriolosclerosis). Mixed effects models examined the linear relation of pathologic indices with global cognitive decline, and random change point models examined the relation of the pathologic indices with the onset of terminal decline and rates of preterminal and terminal decline. Cognition declined an average of about 0.10 unit per year (estimate = -0.101, SE = 0.003, p < 0.001) with considerable heterogeneity in rates of decline (variance estimate for the person-specific slope of decline was 0.0094, p < 0.001). When considered separately, 10 of the 11 pathologic indices were associated with faster decline and accounted for between 2 and 34% of the variation in decline, respectively. When considered simultaneously, the 11 pathologic indices together accounted for a total of 43% of the variation in decline; AD-related indices accounted for 30-36% of the variation, non-AD neurodegenerative indices 4-10%, and cerebrovascular indices 3-8%. Finally, the 11 pathologic indices combined accounted for less than a third of the variation in the onset of terminal decline (28%) and rates of preterminal (32%) and terminal decline (19%). Although age-related neuropathologies account for a large proportion of the variation in late life cognitive decline, considerable variation remains unexplained even after considering a wide array of neuropathologies. These findings highlight the complexity of cognitive aging and have important implications for the ongoing effort to develop effective therapeutics and identify novel treatment targets.

3.
PLoS One ; 16(2): e0245680, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529220

RESUMO

BACKGROUND: This study tested the hypothesis that sarcopenia and its constituent components, reduced lean muscle mass and impaired motor function, are associated with reduced survival and increased risk of incident disabilities. METHODS: 1466 community-dwelling older adults underwent assessment of muscle mass with bioelectrical impedance analysis (BIA), grip strength, gait speed and other components of physical frailty and annual self-report assessments of disability. We used Cox proportional hazards models that controlled for age, sex, race, education and height to examine the associations of a continuous sarcopenia metric with the hazard of death and incident disabilities. RESULTS: Mean baseline age was about 80 years old and follow-up was 5.5 years. In a proportional hazards model controlling for age, sex, race, education and baseline sarcopenia, each 1-SD higher score on a continuous sarcopenia scale was associated with lower hazards of death (HR 0.70, 95%CI [0.62, 0.78]), incident IADL (HR 0.80,95%CI [0.70, 0.93]), incident ADL disability (HR 0.80 95%CI [71, 91]) and incident mobility disability (HR 0.81, 95%CI [0.70, 0.93]). Further analyses suggest that grip strength and gait speed rather than muscle mass drive the associations with all four adverse health outcomes. Similar findings were observed when controlling for additional measures used to assess physical frailty including BMI, fatigue and physical activity. CONCLUSIONS: Motor function is the primary driver of the associations of sarcopenia and physical frailty with diverse adverse health outcomes. Further work is needed to identify other facets of muscle structure and motor function which together can identify adults at risk for specific adverse health outcomes.

4.
Sci Rep ; 11(1): 1588, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452385

RESUMO

We report on interfacial characteristics and chemistry of bonded Mg-Fe interfaces welded using friction stir assisted scribe technique (FaST). Two pairs of dissimilar joints: (AZ31-DP590) and (Pure Mg-DP590) were studied to shed light on joining mechanisms responsible for bonding of "immiscible" pairs of Mg and Fe. We present first direct experimental evidence of presence of oxide layer, Al segregation by atom probe tomography and nano steel grains close to interface by transmission electron microscopy study.

5.
Sci Rep ; 11(1): 1579, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452417

RESUMO

Tuning deformation mechanisms is imperative to overcome the well-known strength-ductility paradigm. Twinning-induced plasticity (TWIP), transformation-induced plasticity (TRIP) and precipitate hardening have been investigated separately and have been altered to achieve exceptional strength or ductility in several alloy systems. In this study, we use a novel solid-state alloying method-friction stir alloying (FSA)-to tune the microstructure, and a composition of a TWIP high-entropy alloy by adding Ti, and thus activating site-specific deformation mechanisms that occur concomitantly in a single alloy. During the FSA process, grains of the as-cast face-centered cubic matrix were refined by high-temperature severe plastic deformation and, subsequently, a new alloy composition was obtained by dissolving Ti into the matrix. After annealing the FSA specimen at 900 °C, hard Ni-Ti rich precipitates formed to strengthen the alloy. An additional result was a Ni-depleted region in the vicinity of newly-formed precipitates. The reduction in Ni locally reduced the stacking fault energy, thus inducing TRIP-based deformation while the remaining matrix still deformed as a result of TWIP. Our current approach presents a novel microstructural architecture to design alloys, an approach that combines and optimizes local compositions such that multiple deformation mechanisms can be activated to enhance engineering properties.

6.
Mol Divers ; 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33392965

RESUMO

Cancer treatment continues to be one of the most serious public health issues in the world. The overexpression of BRD4 protein has led to a series of malignant tumors, hence the development of small molecule BRD4 protease inhibitors has always been a hot spot in the field of medical research. In this study, a series of 4,5-dihydro-[1, 2, 4] triazolo [4, 3-f] pteridine derivatives were used to establish 3D/2D-QSAR models and to discuss the relationship between inhibitor structure and activity. Four ideal models were established, including the comparative molecular field analysis (CoMFA: [Formula: see text] = 0.574, [Formula: see text] = 0.947) model, comparative molecular similarity index analysis (CoMSIA: [Formula: see text]= 0.622, [Formula: see text] = 0.916) model, topomer CoMFA ([Formula: see text] = 0.691, [Formula: see text]= 0.912) model and hologram quantitative structure-activity relationship (HQSAR: [Formula: see text]= 0.759, [Formula: see text] = 0.963) model. They show quite good external predictive power for the test set, with [Formula: see text] values of 0.602, 0.624, 0.671 and 0.750, respectively. In addition, the contour and color code map given by the 2D/3D-QSAR model with the results of molecular docking analyzed to chalk up modification methods for improving inhibitory activity, which was verified by designing novel compounds. The analysis results are helpful to promote the modification of the inhibitor framework and to provide a reference for the construction of new and promising BRD4 inhibitor compounds.

7.
Materials (Basel) ; 13(23)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255717

RESUMO

An aluminum (Al) matrix with various transition metal (TM) additions is an effective alloying approach for developing high-specific-strength materials for use at elevated temperatures. Conventional fabrication processes such as casting or fusion-related methods are not capable of producing Al-TM alloys in bulk form. Solid phase processing techniques, such as extrusion, have been shown to maintain the microstructure of Al-TM alloys. In this study, extrusions are fabricated from gas-atomized aluminum powders (≈100-400 µm) that contain 12.4 wt % TM additives and an Al-based matrix reinforced by various Al-Fe-Cr-Ti intermetallic compounds (IMCs). Two different extrusion techniques, conventional hot extrusion and friction extrusion, are compared using fabricating rods. During extrusion, the strengthening IMC phases were extensively refined as a result of severe plastic deformation. Furthermore, the quasicrystal approximant IMC phase (70.4 wt % Al, 20.4 wt % Fe, 8.7 wt % Cr, 0.6 wt % Ti) observed in the powder precursor is replaced by new IMC phases such as Al3.2Fe and Al45Cr7-type IMCs. The Al3Ti-type IMC phase is partially dissolved into the Al matrix during extrusion. The combination of linear and rotational shear in the friction extrusion process caused severe deformation in the powders, which allowed for a higher extrusion ratio, eliminated linear voids, and resulted in higher ductility while maintaining strength comparable to that resulting from hot extrusion. Results from equilibrium thermodynamic calculations show that the strengthening IMC phases are stable at elevated temperatures (up to ≈ 600 °C), thus enhancing the high-temperature strength of the extrudates.

8.
Entropy (Basel) ; 22(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33286204

RESUMO

Lamellar eutectic structure in Al0.7CoCrFeNi high-entropy alloy (HEA) is emerging as a promising candidate for structural applications because of its high strength-ductility combination. The alloy consists of a fine-scale lamellar fcc + B2 microstructure with high flow stresses > 1300 MPa under quasi-static tensile deformation and >10% ductility. The response to shear loading was not investigated so far. This is the first report on the shear deformation of a eutectic structured HEA and effect of precipitation on shear deformation. A split-Hopkinson pressure bar (SHPB) was used to compress the hat-shaped specimens to study the local dynamic shear response of the alloy. The change in the width of shear bands with respect to precipitation and deformation rates was studied. The precipitation of L12 phase did not delay the formation of adiabatic shear bands (ASB) or affect the ASB width significantly, however, the deformed region around ASB, consisting of high density of twins in fcc phase, was reduced from 80 µm to 20 µm in the stronger precipitation strengthened condition. We observe dynamic recrystallization of grains within ASBs and local mechanical response of individual eutectic lamellae before and after shear deformation and within the shear bands was examined using nano-indentation.

9.
PLoS One ; 15(11): e0242655, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211781

RESUMO

BACKGROUND: Antibody diagnostics play an important role in disease detection and can potentially aid in monitoring of the immune responses to see if an individual has developed immunity. Developing high throughput diagnostics which does not involve handling of infectious material becomes imperative in the case of pandemics such as the recent outbreak of SARS-CoV2. METHODS: A protein microarray technology was used to detect the plurality of antibody response to four novel antigens namely S1 glycoprotein, Receptor binding domain (RBD), S2 glycoprotein and Nucleoprotein of the novel coronavirus named SARS-CoV2 using serum samples. A DBS card was additionally used to compare its performance with a venipuncture-based serum separator tube (SST) draw. RESULTS: The three main subclasses of antibodies IgM, IgA and IgG were analyzed to see the variations in immune responses in the affected population and compared to their microbial RT-PCR based NP swab results. The clinical sensitivity and specificity were determined to be 99.67% and 99.77%. In the matrix comparison study, which would enable patients to test without risk of transmitting the virus, DBS (Dried Blood Spot) matched with higher than 98% accuracy to a venipuncture-based SST collection. CONCLUSION: Multiplex testing enables higher sensitivity and specificity which is essential while establishing exposure on a population scale. This flexible platform along with a discrete collection methodology would be crucial and broadly useful to scale up testing in current and future pandemics. Minimum sample volume that can be collected using DBS cards can be processed in this multiplex pillar plate format enabling the capacity to provide the reliability of high throughput analyzers while having the ease of collection similar to rapid tests.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Isotipos de Imunoglobulinas/sangue , Programas de Rastreamento/métodos , Pneumonia Viral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estados Unidos/epidemiologia , Adulto Jovem
10.
Sci Rep ; 10(1): 18085, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093502

RESUMO

Current serological immunoassays have inherent limitations for certain infectious diseases such as Lyme disease, a bacterial infection caused by Borrelia burgdorferi in North America. Here we report a novel method of manufacturing high-density multiplexed protein microarrays with the capacity to detect low levels of antibodies accurately from small blood volumes in a fully automated system. A panel of multiple serological markers for Lyme disease are measured using a protein microarray system, Lyme Immunochip, in a single step but interpreted adhering to the standard two-tiered testing algorithm (enzyme immunoassay followed by Western blot). Furthermore, an enhanced IgM assay was supplemented to improve the test's detection sensitivity for early Lyme disease. With a training cohort (n = 40) and a blinded validation cohort (n = 90) acquired from CDC, the Lyme Immunochip identified a higher proportion of Lyme disease patients than the two-tiered testing (82.4% vs 70.6% in the training set, 66.7% vs 60.0% in the validation set, respectively). Additionally, the Immunochip improved sensitivity to 100% while having a lower specificity of 95.2% using a set of investigational antigens which are being further evaluated with a large cohort of blinded samples from the CDC and Columbia University. This universal microarray platform provides an unprecedented opportunity to resolve a broad range of issues with diagnostic tests, including multiplexing, workflow simplicity, and reduced turnaround time and cost.

11.
BMC Fam Pract ; 21(1): 165, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32799797

RESUMO

BACKGROUND: As a large number of Community Health Service (CHS) centers in China face the majority of patients with non-valvular atrial fibrillation (NVAF), primary care physicians (PCPs) play a primary role in the prevention of embolization. Therefore, an awareness of anticoagulant management in patients with NVAF must be brought into focus among PCPs in China. This study investigated PCPs' knowledge, attitudes, and practices toward anticoagulant therapy in patients with NVAF, to help them understand their shortcomings regarding oral anticoagulant (OAC) therapy in preventing embolization. METHOD: This was a cross-sectional observational study of 462 PCPs in CHS centers across Shanghai. We used a self-administered questionnaire to collect data from September to December 2017. A stratified random cluster sampling was adopted in the 90 CHS centers with the family medicine residency program. RESULT: Among 462 participants, 69.3% (320/462) of females received a medical bachelor's degree and over 50% of participants had more than 10 years of work experience. Each section for knowledge, attitude, and practice were categorized as poor (≤39.0%), fair (40.0-69.0%), and good (≥70.0%). The level of knowledge of OAC therapy for patients with NVAF among PCPs was insufficient in over half (75.8%) of the participants. The majority (89.8%) of PCPs had a positive attitude and 68.0% had modest performance in the anticoagulant management of patients with NVAF. CONCLUSIONS: The knowledge and behaviors of PCPs were insufficient for OAC therapy to prevent embolization in patients with NVAF. The study also revealed that there is good potential for PCPs' educational interventions to positively impact the care of patients with NVAF.

13.
Medicine (Baltimore) ; 99(30): e21221, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32791696

RESUMO

To decrease postoperative complications in patients with adult lumbar degenerative scoliosis (ALDS), short-segment fusion surgery was used in this study. However, the incidence of adjacent segment disease was found to be remarkable. Therefore, we applied the hybrid treatment (short-segment fusion for responsibility levels plus nonfusion stabilization of lumbar segments, which was called the Wallis system, for the proximal level) to patients enrolled into this study. The purpose of this study was to investigate the feasibility of a novel hybrid therapeutic approach for treating patients with ALDS.From January 2011 to January 2017, a retrospective study was conducted consisting of 16 patients with ALDS who were treated with hybrid treatment. All patients were treated with short-segment decompression and fusion for responsibility levels and nonfusion stabilization of lumbar segments for the proximal levels. The imaging outcomes were evaluated preoperatively and at the time of follow-up.The mean visual analog score for back pain decreased from 6.1 ±â€Š2.0 preoperatively to 2.1 ±â€Š0.7 at 2-year follow-up (P < .05), and the mean visual analog score for leg pain reduced from 8.1 ±â€Š0.6 preoperatively to 1.3 ±â€Š0.8 at 2-year follow-up (P < .05). The Oswestry disability index scores improved from 65.4 ±â€Š16.3% preoperatively to 18.3 ±â€Š5.6% at 2-year follow-up (P < .05). The mean Cobb angle was 22.1 ±â€Š6.2° preoperatively, and 13.8 ±â€Š6.8° at 2-year follow-up (P < .05). The lumbar lordosis changed from -40.4 ±â€Š14.8° to -43.5 ±â€Š11.2° at 2-year follow-up (P < .05). Solid fusion was achieved in all the patients, and no incidence of adjacent segment disease was noted as well.The proposed hybrid treatment for patients with ALDS can achieve favorable clinical outcomes and a lower incidence of ALDS. However, the correction of deformity is still limited that highlights the necessity of further study.


Assuntos
Discotomia/métodos , Vértebras Lombares/cirurgia , Escoliose/cirurgia , Fusão Vertebral/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento , Escala Visual Analógica
14.
BMC Public Health ; 20(1): 990, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576159

RESUMO

BACKGROUND: Today,. most people use the Internet to seek online health-related information from general public health-related websites and discussion groups. However, there are no Internet-based analyses of health information needs pertaining to diabetes in China until now. With the development of artificial intelligence,we can analyzed these online health-related information and provide references for health providers to improve their health service. METHODS: We have done a study of statistically analyzing the questions about diabetes collected from 39 health website, the number of which is 151,589. We have divided these questions into 9 categories using a convolutional neural network. RESULTS: The diabetes problems of consumer are presented as follows, diagnosis: 34.95%, treatment: 25.17%, lifestyle: 21.09%, complication: 8.00%, maternity-related:5.00%, prognosis: 2.59%, health provider choosing: 1.40%, prevention: 1.23%, others: 0.58%, The elderly are more concerned about the treatment and complications of diabetes, while the young are more concerned about the maternity-related and prognosis of diabetes. The diabetes drugs most frequently mentioned by consumers are insulin, metformin and Xiaoke pills, The most concerned complication is caidiovascular disease and diabetic eye disease. CONCLUSION: Diabetes health education should focus on how to prevent diabetes and the contents of health education should be different for differernt age groups;on diabetes treatment, the use of insulin and oral hypoglycemic drugs education should be strengthened.


Assuntos
Informação de Saúde ao Consumidor/estatística & dados numéricos , Diabetes Mellitus , Internet/estatística & dados numéricos , Determinação de Necessidades de Cuidados de Saúde/estatística & dados numéricos , Adulto , Idoso , Inteligência Artificial , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Gravidez , Adulto Jovem
15.
J Orthop Surg Res ; 15(1): 129, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245387

RESUMO

BACKGROUND: Adjacent segment disease (ASD) is an acknowledged problem of posterior lumbar interbody fusion (PLIF). Many studies have been reported concerning the role of lordosis distribution index (LDI) in spinal biomechanics. However, few reports have been published about the impact of LDI on ASD following L4-S1 PLIF. METHODS: The study enrolled 200 subjects who underwent L4-S1 PLIF for degenerative spine disease from 2009 to 2014. The average follow-up term was 84 months. Several lower lumbar parameters were measured, including lower lumbar lordosis (LLL), lumbar lordosis (LL), pelvic incidence (PI), and LDI on the pre and postoperative radiograph. Perioperative information, comorbidities, and operative data were documented. Kaplan-Meier curves were plotted for the comparisons of ASD-free survival of 3 different types of postoperative LDI subgroups. RESULTS: The incidence of ASD was found to be 8.5%. LL and LLL increased by 3.96° (38.71° vs 42.67°; P < 0.001) and 3.60° (26.22° vs 28.82°; P < 0.001) after lower lumbar fusion surgery, respectively. Lordosis distribution index (LDI) increased by 0.03 (0.66 vs 0.69, P = 0.004) postoperatively. A significant difference (P = 0.001) was observed when comparing the incidence of ASD among postoperative LDI subgroups. The Kaplan-Meier curves showed a marked difference in ASD-free survival between low and moderate LDI subgroup (log-rank test, P = 0.0012) and high and moderate LDI subgroup (log-rank test, P = 0.0005). CONCLUSION: Patients with abnormal postoperative LDI were statistically more likely to develop ASD than those who had normal postoperative LDI. Moreover, patients with low postoperative LDI were at greater risk for developing ASD than those with high postoperative LDI over time.

16.
BMC Musculoskelet Disord ; 21(1): 192, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32220255

RESUMO

BACKGROUND: Ankylosing spondylitis (AS) patients with kyphosis have an abnormal spinopelvic alignment and pelvic morphology. Most studies focus on the relationship of pelvic tilt (PT) or sacral slope (SS) and deformity, and relatively few studies have addressed the relationship between pelvic incidence (PI) and kyphosis in AS patients. The purpose of this study is to analyze the correlation between pelvic incidence (PI) and the spinopelvic parameters describing local deformity or global sagittal balance in AS patients with thoracolumbar kyphosis. METHODS: A total of 94 patients with AS (91 males and 3 females) and 30 controls (27 males and 3 females) were reviewed. The mean age was 36.8 years in AS patients and 34.4 years in controls. Gender ratios and mean age were similar in both group. Sagittal spinopelvic parameters, including PI, PT, SS, thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL), sagittal vertical axis (SVA), the first thoracic vertebra pelvic angle (TPA), spinosacral angle (SSA) and spinopelvic angle (SPA) were measured. The same spine surgeons measured all the parameters of the AS and control group. All the sagittal spinopelvic parameters were compared between the groups. The relationship between PI and other spinopelvic parameters was analyzed with Pearson correlation (r) and unary linear regression model. RESULTS: All the sagittal parameters were found to be significantly different between AS patients and controls. Compared with the control group, the AS patients had significantly higher PI(47.4° vs. 43.2°, P < 0.001). Correlation analysis revealed that PI in AS patients was significantly positively correlated with TPA(r = 0.533, R2 = 0.284, P < 0.001), and negatively correlated with SPA(r = - 0.504, R2 = 0.254, P < 0.001). However, no correlations were found between PI and SVA, SSA, TK, TLK or LL in AS patients. CONCLUSION: This study revealed that increasing PI was significantly correlated with more global sagittal imbalance, not with the local deformity in AS patients with thoracolumbar kyphosis.

17.
Ann Neurol ; 87(6): 816-829, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144793

RESUMO

OBJECTIVE: To characterize trajectories of normative cognitive aging. METHODS: Older persons without dementia at study enrollment (n = 1,010) had annual cognitive testing for up to 24 years (mean = 9.9 years, standard deviation = 5.0), died, and underwent a neuropathologic examination to quantify 9 postmortem markers of common neurodegenerative and cerebrovascular conditions. To accommodate the heterogeneity in cognitive trajectories, we used functional mixed effects models, which allow individuals to have different patterns of cognitive decline under a unified model structure. RESULTS: In a functional mixed effects model, postmortem markers (Alzheimer disease pathology, Lewy bodies, transactive response DNA-binding protein 43 pathology, hippocampal sclerosis, atherosclerosis, gross infarcts) were associated with global cognitive decline. Residual global cognitive decline after adjustment for neuropathologic burden was weakly related to age at death; it occurred in only about one-third of participants, mostly proximate to death. Results were comparable after eliminating the initial cognitive assessments to minimize retest learning or controlling for frailty proximate to death. Analyses were also conducted with composite measures of episodic memory and perceptual speed. Residual decline not attributable to neuropathologic burden was confined to a subset for each outcome and was most evident proximate to death. Age at death was unrelated to residual decline in episodic memory but was related to residual decline in perceptual speed. INTERPRETATION: Late life cognitive loss mainly reflects non-normative pathologic and mortality-related processes rather than normative age-related processes. ANN NEUROL 2020;87:816-829.


Assuntos
Envelhecimento/psicologia , Disfunção Cognitiva/psicologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/psicologia , Morte , Escolaridade , Feminino , Fragilidade/psicologia , Humanos , Estudos Longitudinais , Masculino , Memória Episódica , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/psicologia , Exame Neurológico , Testes Neuropsicológicos , Tempo de Reação , Valores de Referência
18.
ACS Omega ; 5(10): 4778-4786, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32201763

RESUMO

Unusual polypyrrole/graphene/cellulose nanofibril (PPy/GR/CNF) composite particles were fabricated by introducing an in situ oxidative polymerization approach. Structural characterization of the composite particles showed foam-like network morphology with a large surface area of 621 m2/g. The PPy/GR/CNF sample exhibited remarkable capacitance behavior in 1 M Na2SO4. It showed a high specific capacitance of 264.3 F/g at 0.25 A/g, which represents a 51.7% increase compared to that of PPy/GR and a high capacitance of 155.5 F/g even at a high current density of 5 A/g. Meanwhile, it possessed high rate capability and good cycling performance (85.7% capacitance retention even after 1000 cycles). These excellent electrochemical performances were attributed to the structure of PPy/GR/CNF that can provide large surface areas and shorten electron diffusion pathways. More importantly, the CNF stabilized the structure of PPy and prevented chain breakdown during the charge/discharge process, which improved the cycling performance. Hence, this PPy/GR/CNF composite shows great potential for the fabrication of high-capacitance and low-cost supercapacitor electrode materials with good cycling performance.

19.
Int J Biol Macromol ; 151: 159-167, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32061851

RESUMO

Cellulose acetate (CA) ultrafiltration membranes are attracting more attention in wastewater purification due to its biodegradability and eco-friendly. The application of CA membranes, however, is limited by high susceptibility to bacterial corrosion and lack of mechanical tolerance that results in loss of life. To solve the above problems, we first fabricated the CA-based composite membranes incorporated with bamboo-based lignocellulose nanofibrils (LCNFs) by a strategy of phase inversion. LCNFs was prepared by using a combined method of one-step chemical pretreatment and acid hydrolysis coupled with high-pressure homogenization. The as-prepared CA/LCNFs composite membranes with 4 wt% lignin in the LCNFs exhibited high tensile strength of 7.08 MPa and strain-at-break of 12.21%, and high filtration permeability of 188.23 L·m-2·h-1 as ultrafiltration membranes for wastewater treatment, which could obviously inhibit the growth of Escherichia coli.

20.
Rev Sci Instrum ; 91(1): 015117, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012594

RESUMO

Despite the challenges, neutron resonance spin echo still holds the promise to improve upon neutron spin echo for the measurement of slow dynamics in materials. We present a bootstrap, radio frequency neutron spin flipper using high temperature superconducting technology capable of flipping neutron spin with either nonadiabatic or adiabatic modes. A frequency of 2 MHz has been achieved, which would achieve an effective field integral of 0.35 T m for a meter of separation in a neutron resonance spin echo spectrometer at the current device specifications. In bootstrap mode, the self-cancellation of Larmor phase aberrations can be achieved with the appropriate selection of the polarity of the gradient coils.

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