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A force sensorless impedance controller is proposed in this paper for robot manipulators without using force estimators. From the observation of the impedance control law, the force feedback term can be canceled if the inertia matrix in the target impedance is the same as the robot inertia matrix. However, the inertia matrix in the target impedance is almost always a constant matrix, while the robot inertia matrix is a function of the robot configuration, and hence, they may not be identical in general. A modification of the coefficient matrix for the contact force term in the target impedance is suggested in this paper to enable cancelation of the force feedback term in the impedance control law so that a force sensorless impedance controller without using force estimators can be obtained. The tracking performance in the free space phase and the motion trajectory in the compliant motion phase of the new design are almost the same as those in the traditional impedance control. Modification of the inertia matrix in the target impedance will result in small variations of the contact force which is acceptable in practical applications. For robot manipulators containing uncertainties, an adaptive version of the new controller is also developed in this paper to give satisfactory performance without the need for force sensors. Rigorous mathematical justification in closed-loop stability is given in detail, and computer simulations are performed to verify the efficacy of the proposed design.
Everyone faces uncertainty on a daily basis. Two kinds of probability expressions, verbal and numerical, have been used to characterize the uncertainty that we face. Because our cognitive concept of living things differs from that of non-living things, and distinguishing cognitive concepts might have linguistic markers, we designed four studies to test whether people use different probability expressions when faced with animate or inanimate uncertainty. We found that verbal probability is the preferred way to express animate uncertainty, whereas numerical probability is the preferred way to express inanimate uncertainty. The “verbal-animate” and “numerical-inanimate” associations were robust enough to persist when tested with forced-choice response patterns regardless of the information (e.g., equally likely outcomes, frequencies, or personal beliefs) used to construct probabilities of events. When the response pattern was changed to free-responses, the associations were evident unless the subjects were asked to write their own probability predictions for vague uncertainty. Given that the world around us consists of both animate (i.e., living) and inanimate (i.e., non-living) things, “verbal-animate” and “numerical-inanimate” associations may play a major role in risk communication and may otherwise be useful for practitioners and consultants.
Over-the-rotor liner exhibits the potential to further attenuate turbofan noise, but the physics involved remain to be explored. In this paper, a three-dimensional coupled singularity method is proposed to investigate the flow-acoustic coupling effects of axially overlapping annular rotor and finite-length liner in subsonic flow. The formulation adopts the orthogonal basis expansion of the generated disturbances in terms of the hard-walled duct modes. The sound scatterings at the rotor and the liner are then characterized, respectively, by the underdetermined dipole and monopole distributions. We derive a simultaneous solution to the coupled unsteady rotor and liner responses, which ensures that the resultant perturbed field satisfies both the impermeable boundary condition on the blade surfaces and the impedance boundary condition on the lined wall. The effect of a perforated porous-material liner on the wake–rotor interaction tones is investigated. The analysis reveals that for the sound field of varying mode and frequency characteristics, moving the inlet liner to the over-the-rotor location generally leads to limited loss or even an increase of upstream sound absorption, along with additional acoustic benefits in the aft duct. The flow-acoustic coupling between the axially overlapping rotor and liner is shown to alleviate significantly the unsteady blade loading and meanwhile intensify the fluid particle oscillation through the acoustically treated wall. Sound source reduction and sound dissipation enhancement are thus identified as the governing noise attenuation mechanisms. Finally, we extend the analysis to provide insights into the effectiveness of over-the-rotor acoustic treatment with shortened axial length.
Vaginitis is a prevalent gynecologic disease that threatens millions of women’s health. Although microscopic examination of vaginal discharge is an effective method to identify vaginal infections, manual analysis of microscopic leucorrhea images is extremely time-consuming and labor-intensive. To automate the detection and identification of visible components in microscopic leucorrhea images for early-stage diagnosis of vaginitis, we propose a novel end-to-end deep learning-based cells detection framework using attention-based detection with transformers (DETR) architecture. The transfer learning was applied to speed up the network convergence while maintaining the lowest annotation cost. To address the issue of detection performance degradation caused by class imbalance, the weighted sampler with on-the-fly data augmentation module was integrated into the detection pipeline. Additionally, the multi-head attention mechanism and the bipartite matching loss system of the DETR model perform well in identifying partially overlapping cells in real-time. With our proposed method, the pipeline achieved a mean average precision (mAP) of 86.00% and the average precision (AP) of epithelium, leukocyte, pyocyte, mildew, and erythrocyte was 96.76, 83.50, 74.20, 89.66, and 88.80%, respectively. The average test time for a microscopic leucorrhea image is approximately 72.3 ms. Currently, this cell detection method represents state-of-the-art performance.
In [2], Beilinson–Lusztig–MacPherson (BLM) gave a beautiful realization for quantum
$\mathfrak {gl}_n$
via a geometric setting of quantum Schur algebras. We introduce the notion of affine Schur superalgebras and use them as a bridge to link the structure and representations of the universal enveloping superalgebra
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
of the loop algebra
$\widehat {\mathfrak {gl}}_{m|n}$
of
${\mathfrak {gl}}_{m|n}$
with those of affine symmetric groups
${\widehat {{\mathfrak S}}_{r}}$
. Then, we give a BLM type realization of
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
via affine Schur superalgebras.
The first application of the realization of
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
is to determine the action of
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
on tensor spaces of the natural representation of
$\widehat {\mathfrak {gl}}_{m|n}$
. These results in epimorphisms from
$\;{\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
to affine Schur superalgebras so that the bridging relation between representations of
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
and
${\widehat {{\mathfrak S}}_{r}}$
is established. As a second application, we construct a Kostant type
$\mathbb Z$
-form for
${\mathcal U}_{\mathbb Q}(\widehat {\mathfrak {gl}}_{m|n})$
whose images under the epimorphisms above are exactly the integral affine Schur superalgebras. In this way, we obtain essentially the super affine Schur–Weyl duality in arbitrary characteristics.
People with serious mental illness are at great risk of suicide, but little is known about the suicide rates among this population. We aimed to quantify the suicide rates among people with serious mental illness (bipolar disorder, major depression, or schizophrenia).
Methods
PubMed and Web of Science were searched to identify studies published from 1 January 1975 to 10 December 2020. We assessed English-language studies for the suicide rates among people with serious mental illness. Random-effects meta-analysis was used. Changes in follow-up time and the suicide rates were presented by a locally weighted scatter-plot smoothing (LOESS) curve. Suicide rate ratio was estimated for assessments of difference in suicide rate by sex.
Results
Of 5014 identified studies, 41 were included in this analysis. The pooled suicide rate was 312.8 per 100 000 person-years (95% CI 230.3–406.8). Europe was reported to have the highest pooled suicide rate of 335.2 per 100 000 person-years (95% CI 261.5–417.6). Major depression had the highest suicide rate of 534.3 per 100 000 person-years (95% CI 30.4–1448.7). There is a downward trend in suicide rate estimates over follow-up time. Excess risk of suicide in males was found [1.90 (95% CI 1.60–2.25)]. The most common suicide method was poisoning [21.9 per 100 000 person-years (95% CI 3.7–50.4)].
Conclusions
The suicide rates among people with serious mental illness were high, highlighting the requirements for increasing psychological assessment and monitoring. Further study should focus on region and age differences in suicide among this population.
We report a family cluster of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection involving five patients in a family cluster in Dazhou, China, including the epidemiological, clinical, laboratory and radiological findings. Three-generation transmission was observed. Through epidemiological investigation, we observed asymptomatic transmission to a cohabiting family member, as well as person-to-person transmission of SARS-CoV-2 outside Wuhan city. The asymptomatic transmission demonstrated here provides evidence that there could be a greater risk of Coronavirus Disease 2019 (COVID-19) spread. This cluster also demonstrated that COVID-19 is transmissible during the incubation period of an asymptomatic person. Early isolation and treatment, stressing prevention of cluster outbreaks, could help prevent further spread of the epidemic.
Salmonella is a leading cause of foodborne outbreaks in Taiwan. On 27 April 2018, a salmonellosis outbreak among customers of a restaurant was reported to the Taiwan CDC. We investigated the outbreak to identify infection sources and prevent further transmission. We interviewed ill customers and their dining companions. We conducted a case-control study to identify foods associated with the illness. Case-patients were those who had diarrhoea within 72 h after eating at the restaurant during 16–27 April 2018. Specimens, food samples and environmental samples were collected and tested for enteric pathogens. Salmonella isolates were analysed with pulse-field gel electrophoresis and whole-genome sequencing. We inspected the restaurant sanitation and reviewed kitchen surveillance camera recordings. We identified 47 case-patients, including one decedent. Compared with 44 controls, case-patients were more likely to have had a French toast sandwich (OR: 102.4; 95% CI: 18.7–952.3). Salmonella Enteritidis isolates from 16 case-patients shared an indistinguishable genotype. Camera recordings revealed eggshell contamination, long holding time at room temperature and use of leftovers during implicated food preparation. Recommendations for restaurant egg-containing food preparation are to use pasteurised egg products and ensure a high enough cooking temperature and long enough cooking time to prevent Salmonella contamination.
To gain more comprehensive understanding of metabolic syndrome (Mets) among in general Chinese population.
Design:
Cross-sectional study. Mets was defined by three widely accepted definitions including modified Adults Treatment Panel (ATP) III criteria, International Diabetes Federation (IDF) criteria and harmonized definition. Risk factors were evaluated by using multivariate logistic regression.
Setting:
Nineteen rural villages in northeast China.
Participants:
The survey was conducted in September 2017 and May 2018 on 10 926 individuals.
Results:
According to modified ATP III criteria, IDF criteria and harmonised definition, the overall prevalence of Mets was 41·3 % (95 % CI 40·3, 42·2), 34·2 % (95 % CI 33·2, 35·1) and 44·1 % (95 % CI 43·1, 45·1), respectively. Females had a higher prevalence, and elevated blood pressure was the most frequent. Age, female sex, non-peasant worker, higher BMI and lower-annual income were independent risk factors of Mets in all three definitions (all ps < 0·05). Based on modified ATP III criteria and harmonised definition, heavy drinking was positively correlated with Mets. In contrast, former drinking was inversely associated with Mets.
Conclusions:
Mets is highly prevalent in rural areas of northeast China. Its independent risk factors include higher age, female sex, non-peasantry worker, higher BMI and lower-annual income. Modified ATP III criteria and harmonised definition may be superior definitions of Mets.
The present study identified the neural mechanism of risky decision-making in Internet gaming disorder (IGD) under a probability discounting task.
Methods
Independent component analysis was used on the functional magnetic resonance imaging data from 19 IGD subjects (22.2 ± 3.08 years) and 21 healthy controls (HC, 22.8 ± 3.5 years).
Results
For the behavioral results, IGD subjects prefer the risky to the fixed options and showed shorter reaction time compared to HC. For the imaging results, the IGD subjects showed higher task-related activity in default mode network (DMN) and less engagement in the executive control network (ECN) than HC when making the risky decisions. Also, we found the activities of DMN correlate negatively with the reaction time and the ECN correlate positively with the probability discounting rates.
Conclusions
The results suggest that people with IGD show altered modulation in DMN and deficit in executive control function, which might be the reason for why the IGD subjects continue to play online games despite the potential negative consequences.
Nanosilver is an environment-friendly, harmless alternative of traditional disinfectants which can be potentially applied in the sericulture industry. However, the effects of nanosilver on the intestinal bacterial community of the silkworms (Bombyx mori L.) are unclear. In this study, Illumina MiSeq high-throughput sequencing technology was used to assess the intestinal bacterial community in both male and female silkworms while treated with different concentrations of nanosilver. We found that nanosilver significantly influenced the composition of silkworm intestinal bacterial community on the different taxonomic levels. Most conspicuously, the abundance of Firmicutes was increased by the treatment of 20 mg L−1 nanosilver but decreased by that of 100 mg L−1 nanosilver at the phylum level. The same trend was observed in Bacilli at the class level and in Enterococcus at the genus level. In some extreme cases, application of nanosilver eliminated the bacterium, e.g., Brevibacillus, but increased the population of several other bacteria in the host intestine, such as Blautia, Terrisporobacter, Faecalibacterium, and some bacteria could only be found in nanosilver treatment groups, e.g., Dialister. In addition, although nanosilver generally showed negative effects on the cocooning rate in a dose-dependent manner, we found that 20 mg L−1 nanosilver treatment significantly increased the body weight of silkworms and did not show negative effects on the survival rate. These results indicated that the intestinal bacteria community of silkworm larvae was significantly changed after nanosilver treatment which might consequently influence host growth and development.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
To eliminate the toxic effect of chemotherapy drug of lobaplatin (LBP) on body tissue in liver cancer therapy, this work prepared a nanodrug carrier based on polyethylene glycol-modified carbon nanotubes (PEG–CNTs) and then constructed a targeted drug delivery system (LBP–PEG–CNTs) by loading LBP on PEG–CNTs. Fluorescein isothiocyanate (FITC) was used to label PEG–CNTs to observe the cellular uptake of PEG–CNTs. In addition, the inhibitions of LBP–PEG–CNTs on HepG2 cells were investigated. The results show that the FITC-labeled PEG–CNTs have good cell penetrability; meanwhile, LBP–PEG–CNTs have good stability, pH-controlled release property, and high inhibition rate on HepG2 cells. To be specific, 80% of LBP is released under physiological conditions of liver cancer cells at pH 5.0, and LBP–PEG–CNTs show a high inhibition rate of 77.86% on HepG2 cells, demonstrating that they have targeted, pH-controlled release and inhibition properties on HepG2 cells.
The Chinese Solar and Geophysical Data (CSGD) was first issued at the Beijing Astronomical Observatory, Chinese Academy of Sciences (now the headquarter of the National Astronomical Observatories, Chinese Academy of Sciences) in 1971, when China’s satellite-industry was booming. CSGD covers the observational data (observations of the sunspots, solar flares, solar radio bursts, ionospheric storm and geomagnetic storm) from a couple of domestic observatories and the forecast data. The compiler of CSGD still keeps the data exchange with other institutes worldwide. The type of the dataset includes texts, tables, figures and so on. Up to now, we have electronized all the historic archives, making them easily accessible to people who are interested in them.
Knotless barbed sutures can eliminate knot tying when patients are undergoing cosmetic surgery (CS). Although benefits reported on clinical outcomes are obvious, many studies have failed to demonstrate the potential for barbed sutures to mitigate adverse events. Thus, this study aimed to determine the safety of knotless barbed suture in CS.
METHODS:
PubMed, EMBASE, Cochrane Register of Clinical Studies, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) and cohort studies comparing barbed sutures with conventional sutures in CS (until 30 June 2016). Quality assessment was conducted using Cochrane recommendations. Review Manager was applied to analyze the data, and we sequentially omitted each study to perform sensitivity analyses.
RESULTS:
A total of five RCTs (low to moderate risk of bias) and six cohort studies (low to moderate risk of bias), proved eligible (3,481 patients). The CS included body contouring operations, breast reconstruction, lipoabdominoplasty, abdominoplasty and wound closure of cesarean delivery. Comparing to conventional sutures, pooling data showed that general adverse events of barbed sutures were not significantly different (Odds Ratio, OR = .6, 95 percent Confidence Interval, CI .24 to 1.52, P = .28), while the subgroup analysis showed that fewer adverse events occurred in cohort studies, though with high heterogeneity (I2 = 87 percent). Specifically, no significant differences were shown between barbed and traditional sutures in wound dehiscence (OR = .55, 95 percent CI .29 to 1.03, P = .06), incisional infection (OR = .56, 95 percent CI .22 to 1.48, P = .25), seroma (OR = .87, 95 percent CI .42 to 1.79, P = .70) and hematoma (OR = 1.52, 95 percent CI .29 to 7.99, P = .62).
CONCLUSIONS:
No differences were found between knotless barbed sutures and conventional sutures generally, but the cohort studies suggested barbed sutures resulted in fewer adverse events with longer follow-up. Thus barbed sutures are considered a safe surgical technique in CS. More evidence with larger sample sizes and longer follow up are needed to confirm the advantages of this technique in the future.
Knotless barbed sutures can eliminate knot tying during the bariatric surgery (BS) (1). Since effects reported by patients and surgeons are ambiguous, the aim of this study was to establish the safety and efficacy of barbed sutures for intestinal sutures to close the gastrojejunal anastomosis in obese patients undergoing BS.
METHODS:
PubMed, EMBASE, Cochrane Register of Clinical Studies, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) and cohort studies comparing barbed sutures with conventional sutures in BS (until 30 June 2016). Quality assessment was conducted using to Cochrane recommendations. Review Manager was applied to analyze the data, and we sequentially omitted each study to perform sensitivity analyses.
RESULTS:
A total of five cohort studies (low to moderate risk of bias) (n = 859), and no RCTs provided eligible patients. BS includes laparoscopic Roux-en-Y gastric bypass and Laparoscopic sleeve gastrectomy. Comparing to conventional sutures, pooling data showed that suture time (Mean Difference, MD = -5.73, 95 percent Confidence Interval, CI -6.25 to -5.21, P < .01) and operative time (MD = - 7.67, 95 percent CI -10.49 to -4.85, P < .01) decreased significantly in the barbed group. Although the postoperative complications did not suggest significant changes (Odds Ratio, OR = 1.56, 95 percent CI .79 to 3.07, P = .2), the pooling results of hospital stay suggested that a significantly longer duration happened in the barbed groups, despite the fact that there may be only 0.18 day longer. (MD =0.18, 95 percent CI .06 to .29, P = .003).
CONCLUSIONS:
The barbed suture is an effective and safe surgical technique in BS. More evidence with randomized design, larger sample sizes and longer follow up need to compel validations of this state-of-the-art product in the future (2,3).
Iron-deficiency anemia is a public health concern that frequently occurs in pregnant mammals and neonatal offspring. Ferrous N-carbamylglycinate chelate (Fe-CGly) is a newly designed iron fortifier with proven effects in iron-deficient rats and weanling piglets. However, the effects of this new compound on pregnant mammals are unknown. Therefore, this experiment was conducted to evaluate the effects of Fe-CGly on sow reproductive performance and iron status of both sows and neonatal piglets. A total of 40 large-white sows after second parity were randomly assigned to two groups (n=20). They were receiving a diet including 80 mg Fe/kg as FeSO4 or Fe-CGly, respectively, from day 85 of gestation to parturition. The serum (day 110 of pregnancy) and placentas of sows were sampled. Litter size, mean weight of live born piglets, birth (live) litter weight, number of live born piglets, and the number of still-born piglets, mummies, and weak-born piglets were recorded. Once delivered, eight litters were randomly selected from the 20 litters per treatment, and one new-born male piglet (1.503±0.142 kg) from each selected litter was slaughtered within 3 h after birth from the selected litters, without colostrum ingestion. The serum, longissimus muscle, liver and kidneys of the piglets were collected. The iron status of the serum samples and the messenger RNA level of iron-related genes in the placenta, liver and kidney were analyzed. The results showed that litter weight of live born piglets was higher (P=0.030) in the Fe-CGly group (19.86 kg) than in the FeSO4 group (17.34 kg). Fe-CGly significantly increased placental iron concentration (P<0.05) of sows. It also significantly increased iron saturation and reduced the total iron-binding capacity of piglets (P<0.05) at birth. However, the results revealed that supplementation of Fe-CGly in sows reduced liver and kidney iron concentration of neonatal piglets (P<0.05), indicating decreased iron storage. In addition, the concentration of iron in the colostrum was not significantly changed. Therefore, the present results suggested that replacement of maternal FeSO4 supplement with Fe-CGly in the late-gestating period for sows could improve litter birth weight, probably via enhanced iron transportation in the placenta.
Previous studies have demonstrated that individuals with Internet gaming disorder (IGD) showed attentional bias toward gaming-related cues and exhibited impaired executive functions. The purpose of this study was to explore the alternations in related functional brain networks underlying attentional bias in IGD subjects.
Methods
Eighteen IGD subjects and 19 healthy controls (HC) were scanned with functional magnetic resonance imaging while they were performing an addiction Stroop task. Networks of functional connectivity were identified using group independent component analysis (ICA).
Results
ICA identified 4 functional networks that showed differences between the 2 groups, which were related to the right executive control network and visual related networks in our study. Within the right executive control network, in contrast to controls, IGD subjects showed increased functional connectivity in the temporal gyrus and frontal gyrus, and reduced functional connectivity in the posterior cingulate cortex, temporal gyrus, and frontal gyrus.
Conclusion
These findings suggest that IGD is related to abnormal functional connectivity of the right executive control network, and may be described as addiction-related abnormally increased cognitive control processing and diminished response inhibition during an addiction Stroop task. The results suggest that IGD subjects show increased susceptibility towards gaming-related cues but weakened strength of inhibitory control.
X-ray powder diffraction data, unit-cell parameters, and space group for ertapenem side chain, C20H19N3O7S, are reported [a = 4.907(6) Å, b = 18.686(3) Å, c = 22.071(1) Å, α = γ = 90°, β = 90.759(5)°, unit-cell volume V = 2023.82 Å3, Z = 4, ρcal = 1.462 g cm−3, and space group P21/c]. All measured lines were indexed and are consistent with the P21/c space group. No detectable impurity was observed.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.