Adverse effects of unilateral transfemoral amputation on para-alpine sit skiers and mitigation methods.

OBJECTIVES: This study aimed to evaluate the adverse effects of unilateral transfemoral amputation on neuromuscular and kinematic parameters in alpine sit skiers, and to determine if additional restraints on the human-bucket interface could help mitigate the effects. DESIGN: Cross-sectional, repeated measures study. METHODS: Simulated skiing tests were conducted indoors involving 10 skiers with unilateral transfemoral amputation and 10 able-bodied participants. A Paralympic silver medalist performed slalom skiing tests on snow. These tests were conducted with and without additional strapping on the residual limb. Surface electromyography of trunk muscles and athletic performance was measured, and the asymmetry index was calculated. RESULTS: Athletes were significantly dependent on muscle activation on the dominant side (asymmetry index = 7.8 %-28.3 %, p < 0.05). Worse athletic performance to the dominant side was found based on inclination angles of the indoor board (asymmetry index = -9.8 %, p = 0.014) and outdoor sit ski (-11.1 %, p = 0.006), and distance to the gate poles during skiing turns (18.6 %, p < 0.001). After using additional restraints, the above asymmetry index declined significantly (asymmetry index < 4.5 %, p < 0.05). Furthermore, athletic performance was significantly improved on both body sides by 11.1 %-30.7 % (p < 0.05). CONCLUSIONS: Unilateral transfemoral amputation caused the dependence on the trunk muscles of the dominant side and the corresponding unilateral poor performance in athletes. Adjusting restraints in the human-equipment interface by additional strapping could mitigate the asymmetry issues and improve athletic performance.

Assessing Obstetric Anal Sphincter Injuries: A Comparison of Exoanal and Endoanal Ultrasound.

OBJECTIVES: To explore the differences in assessing obstetric anal sphincter injuries (OASI) between transperineal ultrasound (TPUS) and endoanal ultrasound (EAUS) and test relationships between ultrasound findings and anal incontinence (AI) symptoms. METHODS: A group of 196 women with a history of vaginal delivery was recruited. OASI was detected in a set of 5 slices by EAUS and 8 slices by TPUS. OASI grading was performed on TPUS rules and EAUS rules. A "significant sphincter defect" was diagnosed by TPUS and EAUS using "2/3 rules." Symptoms of AI were determined using the St Mark's Incontinence Score (SMIS). Ultrasound findings were compared between the two methods and correlated with symptoms. RESULTS: Of 196 women, 29 (14.8%) suffered from AI with a mean SMIS of 12.1 ± 4.5, and 70 (35.7%) women with a mean age of 57 years had suspected OASI on imaging. Twenty-one (10.7%) "significant defects" were diagnosed by TPUS and 24 (12.2%) by EAUS. OASI Grades on TPUS had good agreement with EAUS rules (k = 0.70, P < .001). Logistic regression analysis showed that OASI Grade on imaging and "significant sphincter defects" seen on both forms of imaging were associated with AI symptoms. The odds ratio was 46 and 38 for "significant defects" on TPUS and EAUS, and 14 and 7 for OASI 3b+ on TPUS and EAUS in predicting AI, respectively. CONCLUSIONS: "Significant defects" diagnosed by EAUS or TPUS and OASI Grade 3b+ predict AI symptoms. The diagnostic performance of endoanal and exoanal ultrasound (EAUS and TPUS) appear to be very similar.

Optimization of the Process for Preparing Bivalent Polysaccharide Conjugates to Develop Multivalent Conjugate Vaccines against Streptococcus pneumoniae or Neisseria meningitidis and Comparison with the Corresponding Licensed Vaccines in Animal Models.

OBJECTIVE: This study aimed to describe, optimize and evaluate a method for preparing multivalent conjugate vaccines by simultaneous conjugation of two different bacterial capsular polysaccharides (CPs) with tetanus toxoid (TT) as bivalent conjugates. METHODS: Different molecular weights (MWs) of polysaccharides, activating agents and capsular polysaccharide/protein (CP/Pro) ratio that may influence conjugation and immunogenicity were investigated and optimized to prepare the bivalent conjugate bulk. Using the described method and optimized parameters, a 20-valent pneumococcal conjugate vaccine and a bivalent meningococcal vaccine were developed and their effectiveness was compared to that of corresponding licensed vaccines in rabbit or mouse models. RESULTS: The immunogenicity test revealed that polysaccharides with lower MWs were better for Pn1-TT-Pn3 and MenA-TT-MenC, while higher MWs were superior for Pn4-TT-Pn14, Pn6A-TT-Pn6B, Pn7F-TT-Pn23F and Pn8-TT-Pn11A. For activating polysaccharides, 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) was superior to cyanogen bromide (CNBr), but for Pn1, Pn3 and MenC, N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDAC) was the most suitable option. For Pn6A-TT-Pn6B and Pn8-TT-Pn11A, rabbits immunized with bivalent conjugates with lower CP/Pro ratios showed significantly stronger CP-specific antibody responses, while for Pn4-TT-Pn14, higher CP/Pro ratio was better. Instead of interfering with the respective immunological activity, our bivalent conjugates usually induced higher IgG titers than their monovalent counterparts. CONCLUSION: The result indicated that the described conjugation technique was feasible and efficacious to prepare glycoconjugate vaccines, laying a solid foundation for developing extended-valent multivalent or combined conjugate vaccines without potentially decreased immune function.

Spatiotemporal variations of agricultural water footprint and its economic benefits in Xinjiang, northwestern China.

Agriculture is the largest water user and is the main driving force behind water stress in Xinjiang, northwestern China. In this study, the water footprint (WF) (blue, green and gray WF) of main crop production and their temporal and spatial characteristics in Xinjiang were estimated in 2006, 2010, 2014 and 2018. The blue water footprint deficit (BWFd) was conducted and food productivity and economic benefits of WF were also analyzed via the water consumption per output value (food productivity and economic benefits). The results reveal that the WF increased from 22.75 to 44.16 billion m3 during 2006-2018 in Xinjiang, of which cotton, corn and wheat are main contributors of WF. In terms of different regions, corn has the largest WF in north Xinjiang and cotton has the largest WF in south and east Xinjiang. The BWFd broadened from - 11.51 to + 13.26 billion m3 in Xinjiang with the largest increased BWFd in Kashgar (from - 3.35 to 1.40 billion m3) and Aksu (from - 2.92 to 2.23 billion m3) of south Xinjiang and in Shihezi (from - 0.11 to 2.90 billion m3) of north Xinjiang. In addition, the water footprint food productivity does not well correspond with the water footprint economic benefits in prefectures of Xinjiang. It means we should consider the food yields priority and economic benefits priority to formulate a scientific and effective supervisor mode to realize the sustainable management of agricultural water in prefectures of Xinjiang.

Power Backpack for Energy Harvesting and Reduced Load Impact.

Long-distance walking with heavy loads is often needed when going hiking or for field rescue, which is prone to cumulative fatigue. There is also a great need for labor-saving and biomechanical energy harvesting in daily life for extended security and communication needs. Here, we report a load-suspended backpack for harvesting the wasted energy of human motion based on a triboelectric nanogenerator (TENG). Two elastomers are incorporated into the backpack to decouple the synchronous movement of the load and the human body, which results in little or no extra accelerative force. With such a design, through theoretical analysis and field experiments, the backpack can realize a reduction of 28.75 % in the vertical oscillation of the load and 21.08 % in the vertical force on the wearer, respectively. Meanwhile, the mechanical-to-electric energy conversion efficiency is modeled and calculated to be 14.02 % under normal walking conditions. The designed backpack has the merits of labor-saving and shock absorption as well as electricity generation, which has the promising potential to be a power source for small-scale wearable and portable electronics, GPS systems, and other self-powered health care sensors.

Development and Preliminary Validation of a Pneumatic Focal Vibration System to the Mitigation of Post-Stroke Spasticity.

Some evidence has demonstrated that focal vibration (FV) plays an important role in the mitigation of spasticity. However, the research on developing the FV system to mitigate the spasticity effectively has been seldom reported. To relieve post-stroke spasticity, a new pneumatic FV system has been proposed in this paper. An image processing approach, in which the edge of vibration actuator was identified by the Canny edge detector, was utilized to quantify this system's parameters: the frequency ranging from 44 Hz to 128 Hz and the corresponding amplitude. Taking one FV protocol with the frequency of 87 Hz and the amplitude 0.28 mm of this system as an example, a clinical experiment was carried out. In the clinical experiment, FV was applied over the muscle belly of the antagonist of spastic muscle for twelve chronic spastic stroke patients. Spasticity was quantified by the muscle compliance and area under the curve for muscle (AUC_muscle). The result has demonstrated that, in the state of flexion of spastic muscle, the AUC_muscle and muscle compliance of the spastic muscle significantly increased immediately after FV compared with before-FV, illustrating the mitigation of the spasticity. This study will not only provide a potential tool to relieve post-stroke spasticity, but also contribute to improving the sensory and motor function of patients with other neurological diseases, e.g. spinal cord injury, multiple sclerosis, Parkinson and dystonia, etc.

Lake water volume fluctuations in response to climate change in Xinjiang, China from 2002 to 2018.

Climate change has a global impact on the water cycle and its spatial patterns, and these impacts are more pronounced in eco-fragile regions. Arid regions are significantly affected by human activities like farming, and climate change, which influences lake water volumes, especially in different latitudes. This study integrates radar altimetry data from 2002 to 2018 with optical remote sensing images to analyze changes in the lake areas, levels, and volumes at different altitudes in Xinjiang, China. We analyzed changes in lake volumes in March, June, and October and studied their causes. The results showed large changes in the surface areas, levels, and volumes of lakes at different altitudes. During 2002-2010, the lakes in low- and medium-altitude areas were shrinking but lakes in high altitude areas were expanding. Monthly analysis revealed more diversified results: the lake water levels and volumes tended to decrease in March (-0.10 m/year, 37.55×108 m3) and increase in June (0.03 m/year, 3.48×108 m3) and October (0.04 m/year, 26.90×108 m3). The time series lake water volume data was reconstructed for 2011 to 2018 based on the empirical model and the total lake water volume showed a slightly increasing trend during this period (71.35×108 m3). We hypothesized that changes in lake water at high altitudes were influenced by temperature-induced glacial snow melt and lake water in low- to medium-altitude areas was most influenced by human activities like agricultural irrigation practices.

Temporal-spatial variability of modern climate in the Altai Mountains during 1970-2015.

Located in the intermediate zone between the taiga forests in Siberian Plain and the deserts in Central Asia, the Altai Mountains are of scientific concern about Holocene climate change in the past decades. However, researches about modern climate changes are relatively scarce in the Altai Mountains. In this study, temporal- spatial changes of air temperature and precipitation were investigated systematically in the Altai Mountains based on fifteen meteorological records over the period of 1970-2015. The Altai Mountains experienced a rapid warming trend with a rate of 0.41°C/decade and an insignificantly wetting trend at a rate of 4.82 mm/decade during 1970-2015. The magnitude of temperature trend was negatively correlated with elevation in cold season (spring and winter), whereas that was positively correlated with elevation in warm season (summer and autumn). The cyclonic anomalies to the northwest and an anticyclonic anomalies to the southeast blocked the southward cold air and then provided the favorable condition for an increasing precipitation via the southwesternly wind in the Altai Mountains.

Estimation of regional irrigation water requirements and water balance in Xinjiang, China during 1995-2017.

Estimating water requirements and water balance for irrigated agricultural areas are important and will facilitate the efficient allocation of water resources for agriculture while minimizing the impact on natural ecosystems in arid regions. Based on the Penman-Monteith formula and GIS technology, the irrigation water requirements (IWR) of three main crops (cotton, corn and wheat) during the growing season were estimated and their spatio-temporal changes over the past 23 years (1995-2017) were analyzed in Xinjiang province, China. Our results indicated a dramatic increase in IWR from 14.12 billion m3 in 1995 to 38.99 billion m3 in 2017 due to the rapid cropland expansion of approximately 2.58 × 104 km2 in this period. Monthly IWR usually peaked in summer from May to July and varied in different basins. From the perspective of crops, cotton was identified to have consumed the largest amount of water, reaching 26.39 billion m3 in 2017, accounting for 67.68% of total water consumption. Spatially, the fastest increasing rate of IWR was Tarim Basin, which was attributable to the increase in water requirement of cotton. By comparing IWR and actual irrigation of Xinjiang in 2014, the amount of water scarcity had reached -15.01 billion m3 (-9.80 billion m3 in Tarim Basin and -6.58 billion m3 in Junggar Basin). The planting areas of three main crops (wheat, corn and cotton) were more sensitive to IWR than rising temperature indicated by our model. This study is of great significance for the scientific allocation of water resources in the irrigated areas of the different prefectures of Xinjiang.

Design of the Clutched Variable Parallel Elastic Actuator (CVPEA) for Lower Limb Exoskeletons.

The paper presents a novel clutched variable parallel elastic actuator (CVPEA) mainly consisting of a motor and a flat spiral spring in parallel to actuate the hip of lower limb exoskeletons in sagittal plane. To minimize the power and torque requirement for motor, we put forward three optimization methods including minimizing the rms motor power, the peak motor torque and the peak motor power to determine the optimal PE (parallel elastic) for CVPEA. It is proved that the mechanical energy reduction in the late stance period can be stored in the PE and can be later recycled in the early swing period in a gait cycle according to simulation results. Simulation results also show that using the optimal PE with stiffness of 0.037 Nm/rad, balance position of 0.452 rad determined by minimizing peak motor torque, the rms and peak motor torque, the rms and peak motor can be approximately reduced by 52.3%, 52.9%, 57.5% and 70.2%, respectively, when a subject wearing the CVPEA driven exoskeleton with body weight of 90kg walks at a speed of 0.8 m/s. With this optimal PE, the motor torque and power requirement are largest reduced.

Detection of Concealed Uterine Prolapse in the Volume-Rendering Mode of 4-Dimensional Translabial Ultrasound: A Retrospective Observational Study.

OBJECTIVES: To assess the association between a widened vaginal canal on volume-rendered ultrasound (US) imaging with concealed uterine prolapse. METHODS: This work was a retrospective study of 253 women who had an International Continence Society Pelvic Organ Prolapse Quantification System examination and translabial US examination. The anteroposterior diameter of the vaginal canal was measured in the rendered axial plane for all women. The widened vaginal canal was defined as an anteroposterior diameter above the 95th centile in women with normal uterine descent. The performance of the widened vaginal canal for prediction of clinical uterine prolapse was tested. RESULTS: Valid data from 233 women were analyzed. A mean anteroposterior diameter of 5.6 mm (range, 2.3-10.5 mm; 95th percentile, 10 mm) was seen in 119 women with normal uterine descent. An eye-shaped vaginal canal with a mean anteroposterior diameter of 17.8 mm (range, 10.7-26.8 mm) was seen in 69 women with uterine prolapse. A widened vaginal canal was defined as an anteroposterior diameter of greater than 10 mm. Of 45 concealed uterine descents, 32 had a widened vaginal canal (ie, anteroposterior diameter > 10 mm), and 27 had clinical uterine prolapse. The κ test showed good agreement between physical and US findings (κ = 0.76; P < .001). Ultrasound findings had excellent predictive value (odds ratio, 82.3) for the diagnosis of clinical uterine prolapse. CONCLUSIONS: An eye-shaped vaginal canal with an anteroposterior diameter of greater than 10 mm in the rendered axial plane was a sign of uterine prolapse. This sign may be helpful for detecting concealed uterine prolapse in complex pelvic organ prolapse.

Concordance of tomographic ultrasound and multiplanar ultrasound in detecting levator ani muscle injury in patients with pelvic organ prolapse.

AIM: To compare the evaluations of evaluate levator ani muscle injury (LAMI) by tomographic ultrasound imaging (TUI) and multiplanar (MP) ultrasound in patients with pelvic organ prolapse (POP). METHOD: This retrospective analysis studied women who underwent International Continence Society POP quantification examination between October 2015 and June 2016. LAMI was assessed by both TUI and MP ultrasounds. Concordance of these two testing results was analyzed. Their correlations with clinical symptoms were also studied. RESULTS: A total of 135 women were included. All the patients with POP had a minimal LAMI depth ≥ 7 mm. Two examinations, TUI and MP, had satisfactory concordance (k = 0.71, P < 0.01). Depth of LAMI in the coronal plane demonstrated good agreement with TUI scores (r = 0.84; P < 0.01). After controlling for age, BMI, and parity, to have clinically significant POP and POP symptoms, the odds ratios (ORs) for the depth of LAMI in the coronal plane were 1.31 (95% CI 1.19-1.44) and 1.25 (95% CI 1.14-1.36), and for TUI scores were 1.72 (95% CI 1.37-2.17) and 1.63 (95% CI 1.31-2.03). Receiver operating characteristic curve analyses showed a cutoff depth of 7 mm of LAMI yielded a sensitivity of 62% and specificity of 80% for POP symptoms. CONCLUSIONS: TUI and MP had satisfactory concordance in detecting LAMI and correlated with clinical symptoms of POP.

Evolutionary relationships between seryl-histidine dipeptide and modern serine proteases from the analysis based on mass spectrometry and bioinformatics.

Seryl-histidine dipeptide (Ser-His) has been recognized as the shortest peptide with hydrolysis cleavage activity; however, its protein cleavage spectrum has not yet been fully explored. Here, four differently folded proteins were treated with Ser-His, and the digestion products were evaluated with high-resolution mass spectrometry. The cleavage efficiency and cleavage propensity of Ser-His against these protein substrates were calculated at both the primary and secondary sequence levels. The above experiments show that Ser-His cleaves a broad spectrum of substrate proteins of varying secondary structures. Moreover, Ser-His could cleave at all 20 amino acids with different efficiencies according to the protein, which means that Ser-His has the original digestion function of serine proteases. Furthermore, we collected and compared the catalytic sites and cleavage sites of 340 extant serine proteases derived from 17 representative organisms. A consensus motif Ser-[X]-His was identified as the major pattern at the catalytic sites of serine proteases from all of the organisms represented except Danio rerio, which uses Ser-Lys instead. This finding indicates that Ser-His is the core component of the serine protease catalytic site. Moreover, our analysis revealed that the cleavage sites of modern serine proteases have become more specific over the evolutionary history of this family. Based on the above analysis results, it could be found that Ser-His is likely the original serine protease and maybe the evolutionary core of modern serine proteases.

ADReCS: an ontology database for aiding standardization and hierarchical classification of adverse drug reaction terms.

Adverse drug reactions (ADRs) are noxious and unexpected effects during normal drug therapy. They have caused significant clinical burden and been responsible for a large portion of new drug development failure. Molecular understanding and in silico evaluation of drug (or candidate) safety in laboratory is thus so desired, and unfortunately has been largely hindered by misuse of ADR terms. The growing impact of bioinformatics and systems biology in toxicological research also requires a specialized ADR term system that works beyond a simple glossary. Adverse Drug Reaction Classification System (ADReCS; http://bioinf.xmu.edu.cn/ADReCS) is a comprehensive ADR ontology database that provides not only ADR standardization but also hierarchical classification of ADR terms. The ADR terms were pre-assigned with unique digital IDs and at the same time were well organized into a four-level ADR hierarchy tree for building an ADR-ADR relation. Currently, the database covers 6544 standard ADR terms and 34,796 synonyms. It also incorporates information of 1355 single active ingredient drugs and 134,022 drug-ADR pairs. In summary, ADReCS offers an opportunity for direct computation on ADR terms and also provides clues to mining common features underlying ADRs.

Effects of probiotics on the growth performance and intestinal micro flora of broiler chickens.

Antibiotics have been used in poultry industry for decades to promote growth and protect animals from diseases, followed by various side effects. In efforts of searching for a better alternative, probiotic is of extensive attention. We investigated the effects of Bacillus subtitles, Rhodopseudomonas palustris, Candida utilis and Lactobacillus acidophilus as 0.1% (W/W) feed additives on broiler growth performance and intestinal microflora. The results showed the probiotics treatments significantly improved growth of broilers. Broilers supplemented with B. subtilis and L. acidophilus weighed 18.4% and 10.1% more than birds in control group at 42 days of age. Furthermore the feed conversion ratios of the birds in the two groups were also improved, decreasing 9.1% and 12.9%, respectively. Further study indicated a significant increase of cecal Lactobacilli concentration in briolers supplemented with probiotics, expecially in L. acidophilus treatment group. Meanwhile, the count of cecal Actinomyces in birds treated with probiotics was significantly lower compared with the control group. In conclusion, probiotics such as B. subtitles and L. acidophilus are good alternatives to antibiotics in promoting growth resulting from a beneficial modulation of the intestinal micro flora, which leads to increased efficiency of intestinal digestion in the host animal.

PaGenBase: a pattern gene database for the global and dynamic understanding of gene function.

Pattern genes are a group of genes that have a modularized expression behavior under serial physiological conditions. The identification of pattern genes will provide a path toward a global and dynamic understanding of gene functions and their roles in particular biological processes or events, such as development and pathogenesis. In this study, we present PaGenBase, a novel repository for the collection of tissue- and time-specific pattern genes, including specific genes, selective genes, housekeeping genes and repressed genes. The PaGenBase database is now freely accessible at http://bioinf.xmu.edu.cn/PaGenBase/. In the current version (PaGenBase 1.0), the database contains 906,599 pattern genes derived from the literature or from data mining of more than 1,145,277 gene expression profiles in 1,062 distinct samples collected from 11 model organisms. Four statistical parameters were used to quantitatively evaluate the pattern genes. Moreover, three methods (quick search, advanced search and browse) were designed for rapid and customized data retrieval. The potential applications of PaGenBase are also briefly described. In summary, PaGenBase will serve as a resource for the global and dynamic understanding of gene function and will facilitate high-level investigations in a variety of fields, including the study of development, pathogenesis and novel drug discovery.

A convenient synthesis of N-linked diglycose derivatives based on one-pot tandem Staudinger/aza-Wittig/reduction and biological evaluation.

A series of novel N-linked diglycose derivatives 9 and 10 were conveniently and directly synthesized based on the key step of one-pot tandem Staudinger/aza-Wittig/reduction reaction from the azido sugar and sugar-derived aldehyde followed by deprotection. The biological activities against glycosidases (α-amylase, α-glucosidase, and ß-glucosidase) and HIV-RT and antitumor activity of these compounds were preliminarily evaluated.

Serial ultrasound evaluation of intramyocardial strain after reperfused myocardial infarction reveals that remote zone dyssynchrony develops in concert with left ventricular remodeling.

This study noninvasively evaluated the development of left ventricular (LV) dyssynchrony following reperfused myocardial infarction (MI) in mice using an ultrasonic speckle-tracking method. Eight C57BL/6J mice were assessed by high-resolution echocardiography at baseline and at eight time-points following MI. Images were acquired at 1mm elevational intervals encompassing the entire LV to determine chamber volumes and radial strain. Receiver-operating characteristic (ROC) analysis of regional radial strain was used to segment the three-dimensional (3-D) LV into infarct, adjacent and remote zones. This in vivo segmentation was correlated to histologic infarct size (R = 0.89, p < 0.01) in a short-axis, slice-by-slice comparison. The onset of dyssynchrony during LV remodeling was assessed by standard deviation of time to peak radial strain in the infarct, adjacent and remote zones. It was discovered that the form of LV dyssynchrony that develops in the remote zone late after MI does so in concert with the progression of LV remodeling (R = 0.70, p < 0.05).

Synthetic axial acquisition-full resolution, low-cost C-scan ultrasonic imaging.

The synthetic axial acquisition (SAA) approach presented here is designed to produce C-scan images using low-cost, low bandwidth, front end electronics. We exploit plane wave transmission and shallow C-scan imaging of non-moving, or slowly moving, tissue regions. Between each transmit/receive cycle, the receive sampling trigger is offset by one sampling interval so that over a sequence of acquisitions a sufficiently long data record is synthesized to enable a high-quality approximation to conventional delay and sum beamforming. FIELD II simulations were performed to model the next generation of our sonic window C-scan imaging system using a 5 MHz center frequency, 50% bandwidth, and a 60x60 fully sampled two-dimensional (2- D) array with a 0.3-mm element pitch. These simulations, which include analysis of the impact of target motion both parallel and perpendicular to the acoustic beam, indicate that SAA is robust with respect to target motion no faster than 10 mm/s. The impact of electronic noise on SAA also is considered.