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1.
Microbial fuel cells (MFCs) can ‘treat’ wastewater but individually are thermodynamically restricted. Scale-up might, therefore, require a plurality of units operating in a stack which could introduce losses simply through fluidic connections. Experiments were performed on two hydraulically joined MFCs (20 cm apart) where feedstock flowed first through the upstream unit (MFCup) and into the downstream unit (MFCdown) to explore the interactive effect of electrical load connection, influent make-up and flow-rate on electrical outputs. This set-up was also used to investigate how calculating total internal resistance based on a dynamic open circuit voltage (OCV) might differ from using the starting OCV. When fed a highly conductive feedstock (~4,800 μS) MFCdown dropped approximately 180 mV as progressively heavier loads were applied to MFCup (independent of flow-rate) due to electron leakages through the medium. The conductivities of plain acetate solutions (5 and 20 mM) were insufficient to induce losses in MFCdown even when MFCup was operating at high current densities. However, at the highest flow-rate (240 mL/h) MFCdown dropped by approximately 100 mV when using 5 and 220 mV using 20 mM acetate. When the distance between MFCs was reduced by 5 cm, voltage drops were apparent even at lower flow-rates, (30 mL/h decreased the voltage by 115 mV when using 20 mM acetate). Shear flow-rates can introduce dissolved oxygen and turbulence all capable of affecting the anodic biofilm and redox conditions. Calculating total internal resistance using a dynamic OCV produced a more stable curve over time compared to that based on the starting constant OCV.  相似文献   

2.
Reaction at pH = 2.3 of the [Mo2O2S2(OH2)6]2+ aqua cation with the tetravacant ion [β-B-HAs2W8O31]7− leads to the formation of a red solid from which three mixed salts have been obtained as single crystals and characterized by X-ray diffraction analysis. Three mixed salts K-5a, RbNa-5b, DMACs-5c exhibit a similar molecular arrangement consisting in three {β-HAs2W9O34} subunits mutually linked by three {Mo2O2S2} groups. The triangular arrangement delimits a large open-cavity, lined on the periphery by three outer {As-OH} groups and closed at the bottom by a small hexagonal pocket formed by six terminal oxygen atoms. The central hexagonal cavity is filled either by a potassium, a rubidium or a cesium cation. The outer {As-OH} groups are pointed towards two directions labelled up and down, respectively. In K-6a the three {As-OH} bonds are in up configuration leading to the {up, up, up} isomer. The structure of RbNa-5b is rather consistent with the superposition of the two {up, up, up} and {down, up, up} isomers disordered over the same crystallographic site, while only the {down, up, up} isomer is present in DMACs-5c. In solution, 183W NMR characterization of 6a as sodium salt results in a complicated spectrum consistent with the simultaneous presence of the four isomers, {up, up, up}, {down, up, up}, {down, down, up} and {down, down, down}, respectively. 5a reacts with three equivalents of iodine to give CsNa-6 isolated as single crystals. In 6, four β-{AsW9O33} moieties are located at the corner of a super tetrahedron and are mutually connected by six {Mo2O2S2} linkers. The three outer {As-OH} groups can be selectively removed by iodine, this oxidation reaction consisting in fact in a deprotecting process permitting the extension of the arrangement from triangular to tetrahedral.  相似文献   

3.
The synchronous oscillatory activity characterizing many neurons in a network is often considered to be a mechanism for representing, binding, conveying, and organizing information. A number of models have been proposed to explain high-frequency oscillations, but the mechanisms that underlie slow oscillations are still unclear. Here, we show by means of analytical solutions and simulations that facilitating excitatory (E f) synapses onto interneurons in a neural network play a fundamental role, not only in shaping the frequency of slow oscillations, but also in determining the form of the up and down states observed in electrophysiological measurements. Short time constants and strong E f synapse-connectivity were found to induce rapid alternations between up and down states, whereas long time constants and weak E f synapse connectivity prolonged the time between up states and increased the up state duration. These results suggest a novel role for facilitating excitatory synapses onto interneurons in controlling the form and frequency of slow oscillations in neuronal circuits.  相似文献   

4.
Catabolite repression of Bacillus subtilis catabolic operons is supposed to occur via a negative regulatory mechanism involving the recognition of a cis-acting catabolite-responsive element (cre) by a complex of CcpA, which is a member of the GalR-LacI family of bacterial regulatory proteins, and the seryl-phos-phorylated form of HPr (P-ser-HPr), as verified by recent studies on catabolite repression of the gnt operon. Analysis of the gnt promoter region by deletions and point mutations revealed that in addition to the ere in the first gene (gntR) of the gnt operon (credown), this operon contains another ere located in the promoter region (creup). A translational gntR-lacZ fusion expressed under the control of various combinations of wild-type and mutant credown and creup was integrated into the chromosomal amyE locus, and then catabolite repression of p-galac-tosidase synthesis in the resultant integrants was examined. The in vivo results implied that catabolite repression exerted by creup was probably independent of catabolite repression exerted by credown; both creup and credown catabolite repression involved CcpA. Catabolite repression exerted by creup was independent of P-ser-HPr, and catabolite repression exerted by credown was partially independent of P-ser-HPr. DNase I footprinting experiments indicated that a complex of CcpA and P-ser-HPr did not recognize creup, in contrast to its specific recognition of credown. However, CcpA complexed with glucose-6-phosphate specifically recognized creup as well as credown, but the physiological significance of this complexing is unknown.  相似文献   

5.
Sit-to-stand transfer (STS) is a common yet critical prerequisite for many daily tasks. Literature conducted on healthy STS often assume the body to behave symmetrically across the left and right side; yet only a few studies have been conducted to investigate this supposition. These studies have focused on a single numerical indicator such as peak joint moment (JM) values to describe symmetricity; however, STS is a dynamic and time dependent movement. This study addresses the validity of peak value analyses through the introduction of a time based peak-offset measure and proposes two time-dependent techniques to further characterize asymmetry and assesses their feasibility in ten (10) healthy male participants. JM and joint power (JP) over the whole STS movement was determined using motion capture and inverse dynamics. Using a paired one-tailed t-test differences were found in the time at which the left and right side reached peak values in all lower extremity joints (p<0.05) with exception of the hip JM. Using a measure of JM and JP straight-difference it was determined that the ankle joint displayed the largest number of JM and JP development strategies of all the lower extremity joints. Finally, through numerical integration of the JM and JP data with respect to time, it was found that the longer one side spends dominating the movement, the larger the excess angular impulse and work that can be expected from that side. The results suggest that when analyzing STS movements, one must be aware of the potential asymmetry present even in healthy movements. Furthermore, a simple peak JM or JP analysis may not fully describe the extent of these asymmetries.  相似文献   

6.
Abstract

The effects of different modes of inulin supplementation on caecal fermentation were evaluated in rats. Groups S and IN were fed diets containing 5% of sucrose or inulin, respectively, for the whole experimental period of 40 days. Group IN/S was fed IN and S diets, whereas group S/IN was fed S and IN diets, in the first and the second 20-day period, respectively. Groups INup and INdown were fed diets in which the content of inulin increased from 1 – 5% and decreased from 5 – 1%, every 8 days, respectively. The common effects of inulin on caecal fermentation, i.e. enlargement of tissue, acidification of digesta, a decrease in activities of potentially harmful bacterial enzymes (β-glucuronidase and β-glucosidase), and an increase in the total volatile fatty acids concentration and pool, were especially observed in the IN, S/IN and INup groups. The results suggested that the intensity of caecal fermentation is increased when inulin is present at a relatively high dietary level and that these changes are easily reversible after inulin withdrawal from feed.  相似文献   

7.
The aim of this study, was to determine the prevalence of some respiratory symptoms and possible diseases among taxi drivers and manual workers. This prospective study was performed on 165 Pakistani male drivers, (mean age: 34.5±7.8 years) and 165 Pakistani male manual workers not exposed to dust or fumes, without occupational exposure to driving employed in the Water and Electricity Department and recruited as controls (mean age: 34.6±7.6 years and mean height and weight 169.8±6.0 cm and 71.9±10.9 kg). The data on chronic respiratory symptoms showed that taxi drivers had higher prevalence of symptoms than manual workers, being significantly greater for asthma (RR=1.72; 95% CI=1.00–2.88,P=0.037); allergic rhinitis (RR=2.41; 95% CI=1.46–3.94,P=0.0006); dyspnea (RR=2.13; 95% CI=1.22–3.71,P=0.009); and nasal catarrh (RR=2.19; 95% CI=1.22–3.91,P=0.0106). Thirty percent of taxi drivers and 27% of manual workers were smokers, there was no significant differences in the prevalence of chronic respiratory symptoms between smokers and non-smokers. Lung function parameters in the taxi drivers were significantly lower than in manual workers group (P<0.0001) except PEF parameter. When comparing the measured mean values of lung function parameters in the drivers among smokers and nonsmokers, there was no significant differences between smokers and nonsmokers. Also, a comparison of ventilatory capacity of paired predicted values with measured normal values showed statistically significant differences between predicted and measured values for taxi drivers and manual workers for FVC, FEV1, FEF25–75 and PEF parameters except for FEV1/FVC test in manual workers. In conclusion, the results of the present study provide evidence regarding effects of such as carbon monoxide, nitrogen dioxide, sulfur dioxide and gases exposures on taxi drivers and long-term driving, which may be associated with the development of chronic respiratory symptoms and lung function impairment.  相似文献   

8.

Background

The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample.

Methods/Principal Findings

A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three- to five-fold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as “repetitive strain injury” (RSI).

Conclusions/Significance

The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively.  相似文献   

9.
Although the primary sequence of kinases shows substantial divergence between unrelated eukaryotes, variation in the motifs that are actually phosphorylated by eukaryotic kinases is much smaller. Hence arrays developed for kinome profiling of mammalian cells are useful for kinome profiling of plant tissues as well, facilitating the study of plant signal transduction. We recently employed the Pepscan kinomics chip to reveal the small GTPases in plant sucrose signaling. Here we show that employing a different peptide library (the Pepscan kinase chip) largely similar results are obtained, confirming these earlier data, but such a different library also contributes new insights into the molecular details mediating plant cell responses to a sugar stimulus. Thus when studying plant signal transduction employing peptide arrays, using multiple platforms both increases the confidence of results and provides additional information.Key words: sucrose, arabidopsis, kinome profiling, kinase, MAPK, SnRK, casein kinase, tyrosine phosphorylation, CDC2, AGC kinaseIn our recently published paper1 we analyze the changes in the plant kinome after sucrose feeding compared to control sorbitol feeding of Arabidopsis. We employed kinomics chips (Pepscan Presto, The Netherlands) containing 960 different kinase consensus peptides selected for their importance in mammalian signal transduction. In addition we used kinase chips (Pepscan Presto, The Netherlands), containing 1,152 peptides covering the majority of peptides available through Phosphobase (version 2.0). These chips contain peptides derived from phosphorylation events described in many kingdoms and are taken from animals, plants, fungi and even bacteria.2,3 Full details as to the peptides spotted can be found at www. pepscanpresto.com. Results of the cluster analysis of three independent biological replicas of kinome profiling after treatment with water, sorbitol, sucrose and glucose are depicted in Figure 3A of our recent paper.1 A further analysis of this set of experiments was not given, due to a lower than expected biological reproducibility. In contrast to the >0.8 correlation observed for the set described in our recent paper, correlations of below 0.5 were seen for the experimental set analyzed on the kinase1 chips. However, we feel that some observation made based on these kinome profiles contain valuable information, if only to suggest follow-up experiments.Comparison of the kinome profiles of Arabidopsis treated with sucrose or sorbitol for 1 h revealed a set of 93 differentially phosphorylated consensus peptides, with the majority of 59 peptides showing reduced phosphorylation after sucrose treatment (
ConsensusKinasesor vs. suc t-testP up/down
ESSYSYEEI0.0003down
PASPSPQRQCdk5-p230.0014down
PKRGSKDGAGC0.0019up
IREESPPHS0.0019down
RTPPPSGMAPK0.0020down
PASQTPNKTtCDC20.0029down
STNEYMDMKPI3 kinase0.0030down
SEENSKKTVCKI0.0040down
APTPGGRR0.0043down
RFTDTRKDECaM-III0.0046down
LSELSRRRIds-RNA0.0062up
PINGSPRTPCDC20.0065down
TEGQYELQPTyr-K0.0068up
KRAQISVRGL0.0069down
AKRISGKMA0.0069up
VVGGSLRGAAGC0.0071down
KRPSNRAKA0.0072up
ERQKTQTKLSnRK, MLCK0.0073down
EEGISQESS0.0080up
PVPEYINQSEGFR (Tyr-K)0.0082down
FGHNTIDAV0.0082down
ARVFSVLRECaM-II0.0085down
SNDDSDDDDCKII0.0085down
GGVDYKNIHTyr-K0.0094up
SRSRSRSRS0.0103up
SPSLSRHSSGSK30.0107down
RAKRSGSV0.0120down
RRASLGAGC 1/20.0128down
GRASSHSSQS6K0.0129down
SGYISSLEYCKII0.0139down
FFRRSKIAVAGC0.0140up
STNDSPLbeta-ARK0.0145down
LRRASPG0.0149up
SAVASNMRDGRK0.0154up
KRPSGRAKA0.0160up
KRSNSVDTSAGC0.0165down
RQLRSPRRTCDC20.0171up
GRALSTRAQCDPK, PhK0.0172down
VSRTSAVPTAGC0.0173down
TRKISQTAQAGC0.0174down
STTVSKTET0.0180down
ESPASDEAE0.0184up
LSYRGYSLPhK0.0185down
DDINSYEAW0.0186up
PNVSYIASR0.0191down
KQPIYIVMEFES (Tyr-K)0.0195up
LVVASAGPT0.0198down
TGFLTEYVAMAPKK0.0198up
TEDQYSLVESrc0.0212up
SSSSSPKAEMAPK0.0213up
EKAKSPVPK0.0221down
RRRASVAAGC1/20.0221down
APVASPAAPMAPK0.0225down
LRRLSTKYRAGC1/20.0234down
EKHHSIDAQ0.0256down
VRKRTLRRLSnRK, AGC0.0266down
DLPGTEDFVGRK20.0277down
LSEHSSPEECKII0.0278down
KREASLDNQAGC0.0279down
TKKQSFKQTAGC0.0280up
VRLRSSVPGautoP0.0285down
KRPSLRAKA0.0293up
PGPQSPGSP0.0308down
YSGHSMSDP0.0309up
ADGVYAASGFES (Tyr-K)0.0311up
ENQASEEEDCKII0.0317down
TLASSFKRRAGC0.0324up
TVKSSKGGPAGC0.0326down
GVLRRASVA0.0327up
SPRKSPRKSsperm-specific0.0328down
PRRDSTEGFSnRK, AGC0.0332down
RRRRAASVA0.0346down
SRKDSLDDSGRK0.0371down
ENPEYLGLDTyr-K0.0380down
KAKTTKKRP0.0382up
RRPSV0.0392down
QKAQTERKSAGC0.0401down
AKAKTTKKR0.0404up
GSDVSFNEECKII0.0409down
DEPSTPYHSGSK30.0409down
SSRPSSNRSCDPK, AGC0.0411up
GGRASDYKSAGC0.0413up
YMAPYDNYVTyr-K0.0420up
LELSDDDDCKII0.0422down
THVASVSDVSnRK AMPK0.0423down
SMANSFVGTPDKI0.0427down
DLLTSPDVGCDC20.0441down
RGKSSSYSKAGC0.0441up
SSSNTIRRPAGC0.0453up
RRDSV0.0457down
TKAASEKKS0.0469up
DRLVSARSVCDPK, SnRK, AGC0.0480down
RLSISTESQAMPK0.0489up
Open in a separate windowArabidopsis seedlings were incubated in a solution of 100 mM sucrose or sorbitol for 1 hour after which extracts were made as described before (Plos One) and incubated on Kinase1 PepChips (1152 consensus peptides spotted twice per slide; Pepscan). The averaged phosphorylation intensities obtained from three independent experiments were analyzed using a Student’s t-test. Indicated is whether phosphorylation of consensus peptides is higher (up) or lower (down) after sucrose treatment, compared to sorbitol. Kinase annotation according to Pepscan Presto (www.pepscanpresto.com), or our own analysis (see main text).  相似文献   

10.
Frequency and severity of musculoskeletal symptoms in humans during an outbreak of trichinellosis caused by Trichinella britovi     
Akar S  Gurler O  Pozio E  Onen F  Sari I  Gerceker E  Gunes AJ  Akinci B  Birlik M  Akkoc N 《The Journal of parasitology》2007,93(2):341-344
Musculoskeletal symptoms such as myalgia are well-known features in the course of trichinellosis; however, the characteristics of musculoskeletal findings have been described in detail in only 1 study. The present study was aimed to determine the joint and muscle symptoms in subjects diagnosed with acute trichinellosis at our rheumatology unit during a Trichinella britovi outbreak that occurred in Izmir, Turkey, in 2004. In total, 98 patients (55 females, 43 males; mean age 32.3 +/- 10.9 yr) were included in the study. A detailed history and full musculoskeletal examination were obtained in each patient. A self-administered questionnaire developed for recording the musculoskeletal symptoms was completed monthly until all the symptoms were resolved. Pain at the joints, restriction of movements (in shoulders, elbows, wrists, knees, ankles, and temporomandibular joints), myalgia, and muscle weakness (neck and shoulder girdle, muscles of the upper and forearm, back, thigh, and calf muscles) were assessed in every patient. Eosinophil counts, serum levels of creatine kinase, and lactate dehydrogenase also were analyzed. The most frequent musculoskeletal symptoms were muscle pain (86 cases [87.8%]), joint pain (83 [84.7%]), subjective muscle weakness (75 [76.5%]), and restriction of joint movements (63 [64.3%]). Calves, upper arm, neck and shoulder girdle, and forearms were the most affected muscle groups. Muscle pain was reported more frequently in the upper than in the lower extremities and during activity. The most frequent painful joints were shoulders, knees, wrists, and ankles. Upper extremity joints were affected more frequently than the lower extremity joints (77.6 vs. 70.4%). Joint pain occurred more frequently at rest. Both muscle weakness and restriction of joint movements were reported in and around the most frequently affected regions. No evidence of arthritis and objective muscle weakness was noted on physical examination in any patient. Musculoskeletal symptoms in the course of T. britovi infection are frequent but with an excellent prognosis. Joint pain in people suffering from acute trichinellosis may occur more frequently than reported previously.  相似文献   

11.
Thermophilic high-rate anaerobic treatment of wastewater containing long-chain fatty acids: impact of reactor hydrodynamics   总被引:2,自引:0,他引:2  
C.-S. Hwu  G. Molenaar  J. Garthoff  J.B. van Lier  G. Lettinga 《Biotechnology letters》1997,19(5):447-451
The liquid superficial up_ow velocity (Vup) and hydraulic retention time (HRT) on the thermophilic treatment of oleate in expanded granular sludge bed (EGSB) reactors were investigated. The highest methane conversion rate of oleate, 93 mg CH4-COD/g VSS.d, was attained in a reactor operating at a Vup of 1 m/h and an HRT of 24 h. The typical EGSB reactor hydrodynamics (Vup > 4 m/h and HRT < 10 h) inhibited the treatment performance, mainly due to biomass washout in particulate form. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

12.
The influence of visual display terminal use on the physical and mental conditions of administrative staff in Japan     
Ye Z  Abe Y  Kusano Y  Takamura N  Eida K  Takemoto T  Aoyagi K 《Journal of physiological anthropology》2007,26(2):69-73
Visual display terminals (VDT) are standard equipment for many office workers. Their use, however, may increase the risk of developing adverse conditions related to vision, the musculoskeletal system, and mental health. We carried out a survey among 3070 workers aged 18 to 67 years (mean, 39.9 years) at a prefectural administrative office, in which 76% of subjects were visual display terminal (VDT) users. We examined the relationship between duration of daily VDT use and eyestrain, neck or upper extremity pain, back pain, and mental health, and estimated the effect of breaks and rest during VDT work on these symptoms. The 12-item General Health Questionnaire (GHQ-12: total scores ranged from 0 to 12) was used to identify potential poor mental health status, and subjects with 4 or more were considered to have symptoms of psychological distress. Seventeen percent of subjects reported eyestrain, 19.1% reported upper extremity pain, 11.6% reported back pain, and 17% of subjects had GHQ-12 scores of 4 or higher. Logistic regression analysis showed that duration of daily VDT use and lack of breaks and rest during VDT work were significantly associated with eyestrain, neck or upper extremity pain, back pain, and psychological distress. In order to protect users from the adverse effects associated with VDT work, reducing daily VDT exposure, taking breaks, and rest during VDT work are important.  相似文献   

13.
Dynamic Frequency Analyses of Lower Extremity Muscles during Sit-To-Stand Motion for the Patients with Knee Osteoarthritis     
Masaya Anan  Koichi Shinkoda  Kentaro Suzuki  Masahide Yagi  Nobuhiro Kito 《PloS one》2016,11(1)

Objective

Muscle activities during the sit-to-stand motion (STS) are characterized by coordinated movements between hip extensors and knee extensors. However, previous reports regarding the STS and lower extremity muscle activities have focused on some quantitative assessment, but little qualitative research. This study aimed to examine the muscle activities of the lower extremity both quantitatively and qualitatively.

Methods

Study participants included 13 patients with knee osteoarthritis (knee OA) and 11 age-matched asymptomatic controls. The task was STS from a chair with a height-adjustable seat. EMG activities were acquired using surface electromyogram. The root mean square signals normalized as a percentage of maximum voluntary isometric contraction values (RMS%MVC) and the mean power frequency (MPF) were calculated.

Results

During STS, knee OA patients had increased RMS%MVC of the vastus medialis and raised MPF of the rectus femoris before buttocks-off.

Conclusion

These findings suggest that STS of knee OA patients not only increased relative muscle activity of the vastus medialis, but also enlisted the rectus femoris in knee extension to improve muscle contraction force by activating more type II fibers to accomplish buttocks-off.  相似文献   

14.
Occupational disparities in survival from common cancers in Japan: Analysis of Kanagawa cancer registry     
《Cancer epidemiology》2022
BackgroundLittle is known about occupational disparities in survival for common cancer sites in Japan.MethodsUsing data from a population-based cancer registry, we identified 32,870 cancer patients diagnosed during 1992–2011. We followed the patients for 5 years (median follow-up time 5.0 years). For each individual, we classified their longest-held occupation into 5 classes (upper non-manual, lower non-manual, manual, farmer, and others) following the Erikson-Goldthorpe-Portocarero scheme. Poisson regression models were used to estimate overall and site-specific mortality rate ratios (MRRs) and 95% confidence intervals (CI) for each occupational class, adjusted for sex, age, and diagnosis year. Upper non-manual workers served as the reference group. Additionally, using a binary categorization of occupations (manual workers versus non-manual workers), a causal mediation analysis with 4-way decomposition was performed to investigate the potential mediation of the association between occupation and overall mortality by cancer stage.ResultsOverall prognosis was good in this population (5-year overall survival was 81.7%). Compared with upper non-manual workers, both overall and cancer-specific mortality was higher in lower non-manual workers (MRR=1.14, 95% CI 1.05–1.24) and manual workers (MRR=1.40, 95% CI 1.29–1.53). After adjusting for the mediating influence of prognostic factors (stage and treatment), the observed occupational differences were attenuated but remained significant in manual workers: MRR = 1.23 (95% CI 1.08–1.39). Observed occupational disparities tended to be attributable to common cancers, i.e., stomach and lung among men and female breast cancer. Additionally, manual workers had 1.25 times higher odds for advanced stage. In the mediation analysis, the overall proportion explained by mediating effect of cancer stage was 29% (4% due to mediated interaction and 25% due to pure indirect effect).ConclusionWe documented occupational disparities in survival from commonly-occurring cancers in Japan. Occupational differences in cancer stage may explain one-third of the survival disparities.  相似文献   

15.
Computational stability of human knee joint at early stance in Gait: Effects of muscle coactivity and anterior cruciate ligament deficiency     
《Journal of biomechanics》2017
As one of the most complex and vulnerable structures of body, the human knee joint should maintain dynamic equilibrium and stability in occupational and recreational activities. The evaluation of its stability and factors affecting it is vital in performance evaluation/enhancement, injury prevention and treatment managements. Knee stability often manifests itself by pain, hypermobility and giving-way sensations and is usually assessed by the passive joint laxity tests. Mechanical stability of both the human knee joint and the lower extremity at early stance periods of gait (0% and 5%) were quantified here for the first time using a hybrid musculoskeletal model of the lower extremity. The roles of muscle coactivity, simulated by setting minimum muscle activation at 0–10% levels and ACL deficiency, simulated by reducing ACL resistance by up to 85%, on the stability margin as well as joint biomechanics (contact/muscle/ligament forces) were investigated. Dynamic stability was analyzed using both linear buckling and perturbation approaches at the final deformed configurations in gait. The knee joint was much more stable at 0% stance than at 5% due to smaller ground reaction and contact forces. Muscle coactivity, when at lower intensities (<3% of its maximum active force), increased dynamic stability margin. Greater minimum activation levels, however, acted as an ineffective strategy to enhance stability. Coactivation also substantially increased muscle forces, joint loads and ACL force and hence the risk of further injury and degeneration. A deficiency in ACL decreases total ACL force (by 31% at 85% reduced stiffness) and the stability margin of the knee joint at the heel strike. It also markedly diminishes forces in lateral hamstrings (by up to 39%) and contact forces on the lateral plateau (by up to 17%). Current work emphasizes the need for quantification of the lower extremity stability margin in gait.  相似文献   

16.
Social Behaviour on the Wing in the False Vampire,Megaderma lyra     
Dieter Leippert 《Ethology : formerly Zeitschrift fur Tierpsychologie》1994,98(2):111-127
Social interaction occurs in bats. In a group of 10 Megaderma lyra (seven female and two male adults, as well as one female juvenile) held in captivity, two stereotyped flying behaviour patterns —the ‘grumbling flight’ and the ‘song flight’ — were observed and studied. The ‘grumbling flight’ is a social interaction in flight between at least two Megaderma lyra in which ‘grumble sequences’ are emitted. This behaviour is triggered by stress or arising aggression, and presumably attempts to avoid agonistic interactions with dangerous physical contact. The song flight was exclusively displayed by the dominant male bat and only directed at the non-lactating female members of the group, with a preference to alien females. This behaviour is composed of three behavioural stages, each accompanied by a specific ‘song strophe’. The song flight presumably aims at bonding the females to the male. During the grumbling flight and the song flight, M. lyra emits communication sounds in the ultrasonic range. The sounds consist of simple elements (FMdown, FMup, CF), and are similar to types of sounds emitted for echolocation by various bat species.  相似文献   

17.
Influence of eccentric strength of knee extensor muscles on biomechanical factors of a vertical drop jump     
《Journal of electromyography and kinesiology》2022
During a vertical drop jump (VDJ), the human neuromuscular system absorbs and reuses external loads applied to the lower extremity by coordinating the musculoskeletal system. This study aims to investigate the influence of the eccentric strength of the knee extensor muscles on the biomechanical factors of a VDJ. Participants were divided into two groups based on the eccentric strength of their knee extension muscles: low eccentric (LECC) and high eccentric (HECC) strength groups. The VDJ joint kinematics and kinetics of the lower extremity, the fascicle behavior of the vastus lateralis, and the muscle activation of the knee extensor muscles were simultaneously recorded during maximum-effort VDJ. Compared with the LECC group, the HECC group showed a higher jump, greater knee and ankle joint stiffness, and smaller fascicle length change. These findings suggest that the eccentric strength capacity of the knee extensor muscles accounts for the different biomechanical strategies (bouncing-type for HECC and absorbing-type for LECC) observed between the groups. Consequently, the eccentric strength of the knee extensor muscle may be an essential factor in determining the biomechanical strategy for VDJ and should be considered in the jumping performance enhancement training paradigm.  相似文献   

18.
平衡功能训练联合肌内效贴对脑卒中偏瘫患者平衡功能、步行功能和生活质量的影响          下载免费PDF全文
罗晓华  陈丽玲  何素玲  黄喜顺  阮兢 《现代生物医学进展》2021,(18):3502-3506
摘要 目的:观察脑卒中偏瘫患者经肌内效贴联合平衡功能训练治疗后,其步行功能、生活质量及平衡功能的变化。方法:于2018年6月~2020年8月期间,选取我院收治的300例脑卒中偏瘫患者,根据随机数字表法分为对照组(150例,常规康复训练和平衡功能训练)和研究组(150例,常规康复训练、平衡功能训练联合肌内效贴),均治疗4周。对比两组平衡功能、步行功能、生活质量、睁眼站立、脚前后站立、闭眼站立的重心摆动速度及动态稳定时间。结果:治疗4周后,两组Fugl-Meyer下肢运动功能评定量表(FMA)、Berg平衡量表(BBS)评分较治疗前升高,且研究组高于对照组(P<0.05)。治疗4周后,两组步行功能指标:步频、步长、步速、步幅较治疗前升高,且研究组高于对照组(P<0.05)。治疗4周后,两组SF-36各维度评分较治疗前升高,且研究组高于对照组(P<0.05)。治疗4周后,两组睁眼站立、脚前后站立、闭眼站立的重心摆动速度和动态稳定时间较治疗前降低,且研究组低于对照组(P<0.05)。结论:脑卒中偏瘫患者经肌内效贴联合平衡功能训练治疗后,平衡功能得到较好的恢复,步行能力提高,其生活质量得到改善。  相似文献   

19.
Sickness absence among municipal workers in a Brazilian municipality: a secondary data analysis     
Ana Lucia M. Leao  Anadergh Barbosa-Branco  Marília D. Turchi  Ivan A. Steenstra  Donald C. Cole 《BMC research notes》2017,10(1):773

Background

Sickness absence, work disability associated with illness or injury, is a major public health problem worldwide. Some studies have investigated determinants of sickness absence among workers with shorter job tenure, but have only focused on certain diagnostic groups. Although it is well established that job tenure has an inverse relationship with work injury rate, less is known about its association with sickness absence for other disorders. Therefore, this study aimed to investigate the risk factors for incidence and duration of sickness absence according to diagnosis over a 7-year period. A dynamic cohort consisting of all permanent civil servants hired from 2005 to 2011 by the Goiania municipality-Brazil. Data of certified sickness absences longer than 3 days were analyzed. The incidence density was calculated per 1000 person-years in each ICD-10 category. The association between sickness absence and socio-demographic and occupational characteristics was examined using negative binomial regression models.

Results

18,450 workers, mean age of 32 years, accumulated 14,909 episodes of sickness absence. Overall, the incidence density was 234.6 episodes per 1000 person years. Diagnostic groups with the highest incidence density of sickness absences were injuries (49.1), musculoskeletal disorders (31.3) and mental disorders (29.2). Factors predicting any sickness absence were female gender, older age, low education, being a health professional, multiple jobs and full-time employment. Mental health disorders were more common among education professionals, musculoskeletal disorders among blue collar workers and injuries among inspection workers. Prolonged time on sick leave was associated with male gender, older age groups, low education and income, blue-collar workers, more than one job contract and full time employment.

Conclusions

These findings demonstrate a substantial sickness absentee burden and they provide relevant information for targeting prevention and health promotion policies to the most vulnerable occupational groups.
  相似文献   

20.
Psychosocial Work Environment and Musculoskeletal Symptoms among 21-Year-Old Workers: A Population-Based Investigation (2011-2013)     
Sara Louren?o  Filomena Carnide  Fernando G. Benavides  Raquel Lucas 《PloS one》2015,10(6)

Background

The current labour market is becoming more flexible and informal, with job insecurity selectively affecting young workers. However, the role of these increasing adverse psychosocial working conditions on health outcomes remains little known among newly employed workers.

Objective

To estimate the associations between psychosocial work environment and musculoskeletal outcomes (widespread pain syndrome features and regional pain) in a population-based sample of young workers.

Methods

Cross-sectional data from workers aged 21 years were collected during the third wave of the EPITeen cohort study (2011-2013; n=650). The Job Content Questionnaire was used to characterize the psychosocial work environment according to the demand-control-support model. Data on pain and non-pain dimensions of the widespread pain syndrome (Fibromyalgia Survey Questionnaire) as well as on regional musculoskeletal pain (Nordic Musculoskeletal Questionnaire) were also collected. Crude and adjusted odds ratios (OR) with 95% confidence intervals (95% CI) were computed using logistic regression and all estimates were adjusted for sex, education and occupational biomechanical demands.

Results

Job insecurity was significantly associated to the non-pain dimension of the widespread pain syndrome (adjusted OR [95% CI]=1.51 [1.08, 2.12]). Young workers with strain jobs were significantly more likely to report high levels of non-pain symptoms when compared with those with no-strain jobs and this effect was even stronger when social support was added to the main exposure: workers with strain jobs and low social support had twice the odds of reporting high levels of non-pain features than those with high strain but high social support jobs (adjusted OR=1.86, 95% CI: 1.04, 3.31). These significant associations were not observed when widespread pain or multisite regional pain were the outcomes.

Conclusion

In the beginning of professional life, high strain jobs were associated to non-pain complaints, especially when the work environment provided also low social support.  相似文献   

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