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Integrons are important genetic elements that allow easy acquisition and dissemination of antimicrobial resistance genes. Studies reporting occurrence of integrons in Staphylococcus aureus (S. aureus) isolated from bovine mastitis in large dairy farms across China are scarce. The aim of this study was to investigate the occurrence of class 1 integrons (intI1), antimicrobial resistance (AMR) and associated genes in S. aureus isolated from bovine mastitis and their associations. Minimum inhibitory concentrations (MICs) were determined to evaluate the AMR phenotypes, whereas PCR was carried out to assess the occurrence of AMR genes and intI1. In addition, index cluster analysis was used to estimate associations between AMR phenotype, genotype and intI1 in 103 isolates. Overall, 83% of S. aureus were intI1-positive and 5 types of gene cassettes were detected. Susceptibility against single antimicrobial agents ranged from 0% (erythromycin), 12% (ampicillin) and 16% (penicillin G) to 96% (gentamicin). Most isolates (64%) were intermediate-resistant against erythromycin, whereas resistance against ceftriaxone (22%), clindamycin (4%), cefotaxime (2%), tetracycline (1%) and ciprofloxacin (1%) were relatively uncommon. The predominant resistant gene was blaZ gene (n = 88, 85%) followed by tetD gene (n = 85, 83%). With an estimated prevalence of 12% of the mecA gene, methicillin-resistant S. aureus isolates had higher MIC50 and MIC90 for majority of antimicrobials than methicillin-susceptible S. aureus isolates. Presence of the ermC gene was associated with erythromycin resistance. Ampicillin, erythromycin and penicillin G resistance were associated with intI1. The data presented in our study indicated that class 1 integron-mediated resistance possibly plays an important role in dissemination of AMR in S. aureus isolated from bovine mastitis.
Using monthly data from 1978:M1 to 2019:M9, this paper provides empirical evidence concerning the role that monetary policy plays in the US housing market. We first show that shocks to short-run interest rates have significant impacts on house prices and that these effects are persistent. Our findings also provide evidence supporting the claim that too-low-for-too-long interest rates are responsible for the 2002–2006 US housing boom. We further investigate the different channels through which an easing monetary policy fuels the house price boom and find that faster sales and lower inventory levels in the housing market most amplify the policy effects. Lastly, we provide compelling evidence of the asymmetric effects of contractionary and expansionary monetary policies on house prices.
To contribute to the treatment decision and optimize coagulase-negative staphylococcus (CNS) control programs, we conducted a meta-analysis to investigate the epidemiology and antimicrobial resistance rates of coagulase-negative staphylococcus associated with bovine mastitis in China. Three databases (PubMed, Google scholar and China National Knowledge Infrastructure database) were utilized to obtain relevant publications. A total of 18 publications were included in our research, and 3 of them included antimicrobial resistant (AMR) test. The pooled prevalence of coagulase-negative staphylococcus was 17.28%. Subgroup analysis revealed that the prevalence was higher in South China than in North China, was higher in 2011–2020 than in 2000–2010 and was higher in clinical bovine mastitis cases than in subclinical cases. The pooled AMR were most resistant to β-lactams, followed by tetracyclines, quinolones, nitrofurans, lincosamides, sulfonamides, amphenicol and aminoglycosides. The pooled AMR rate of coagulase-negative staphylococcus was lower in 2011–2020 than in 2000–2010. Although the prevalence of CNS showed an increasing trend over 20 years, the AMR rate showed a decreasing trend, and the clinical type of mastitis was the most frequent and the prevalence was highest in South China. Finally, CNS was most resistant to β-lactams amongst the eight groups of antimicrobial agents.
Objectives: Central-line–associated bloodstream infection (CLABSI) has been the leading cause of healthcare-associated infections (HAIs) in the intensive care unit (ICU) setting. Previous studies have shown that a care bundle is effective in reducing CLABSI rates; however, the data on long-term sustainability and cost savings of bundled care are limited. Methods: From January 2011 to December 2020, a prospective surveillance was performed to monitor CLABSI at a university hospital in northern Taiwan. To reduce the CLABSI rate, a hospital-wide bundled care program for CLABSI prevention was implemented in 2013. We evaluated the long-term effect of the care bundle on CLABSI incidence and length of stay in the ICU. Results: During the study period, the overall CLABSI incidence decreased from 8.22 per 1,000 catheter days before the care bundle was implemented to 6.33 per 1,000 catheter days in 2020 (P for trend <.01). The most common pathogens causing CLABSI were gut organisms (1,420 of 2,363, 60.1%), followed by environmental organisms (734 of 2,363, 31.1%) and skin organisms (177 of 2,363, 7.5%). The decreasing trend was statistically significant in the incidence of CLABSI caused by skin organisms (P for trend < .01), but not in the incidence of CLABSI caused by environmental organisms (P for trend = .86) or gut organisms (P for trend = .06). In the multivariable analysis, implementation of this care bundle was independently associated with a decrease in the CLABSI rate (RR, 0.77; 95% CI, 0.66–0.88). Compared with patients without CLABSI, patients with CLABSI had a longer average ICU length of stay (27 vs 17 days). Conclusions: A sustainable reduction in the incidence of CLABSI caused by common commensals could be achieved through a cost-saving bundled care program.
The differential impact of depression across different periods in life on mortality remains inconclusive. We aimed to examine the association of depression that occurs at different age with all-cause mortality, and to explore the roles of dementia, as well as genetic and early-life environmental factors, in this association.
Methods
From the Swedish Twin Registry, 44,919 twin individuals were followed for up to 18 years. Depression was ascertained using the National Patient Registry and categorized as early-life (<45 years), midlife (45–64 years), and late-life (≥65 years) depression according to the age of the first diagnosis. Deaths were identified through the Cause of Death Register. Generalized estimating equation, generalized structural equation, and conditional logistic regression were used for unmatched, mediation, and co-twin matched analyses, respectively.
Results
In unmatched analyses, the multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of mortality were 1.71 (1.46–2.00) for depression at any age, 1.72 (1.36–2.17) for early-life, 1.51 (1.19–1.90) for midlife, and 4.10 (2.02–8.34) for late-life depression. Mortality was significantly higher in individuals with late-life depression than those with earlier-life depression (p < 0.05). The mediation analysis showed that 59.83% of the depression-mortality association was mediated by dementia. No significant difference in ORs between the unmatched and co-twin matched analyses was observed (p = 0.09).
Conclusions
Depression is associated with an increased risk of all-cause mortality, and dementia mediates approximately 60% of the impact of depression on mortality in late life. Genetic and early-life environmental factors may not play a significant role in the depression-mortality association.
This article shows that the descriptions of Southeast Asian geography contained in Ming and Qing Chinese sources that used observations collected from contemporary mariners reflect the structure of the maritime trading networks in the region. It examines several Chinese textual studies of Southeast Asia, navigational rutters, and maps, and uses geographic information system mapping to visualise and compare the extent of the authors’ and cartographers’ knowledge of the region. The article then takes the findings and situates them in the context of early modern Southeast Asian economic history to explain how the Chinese networks were transformed.
Many components in diet have regulated oxidative stress, inflammatory reaction and even balance oestrogen levels. Because these factors are closely associated with depressive symptoms in postmenopausal women, it is considered that dietary factors are able to prevent and control depressive symptoms. On the other hand, a dietary pattern that considers the correlations and synergies between foods and nutrients is expected to have a greater impact on disease risk. The aim of the present study is to evaluate whether dietary patterns are associated with depressive symptoms in Chinese postmenopausal women. A cross-sectional study of 2051 postmenopausal women (mean age: 58·8 (sd 7·4) years) was conducted in Tianjin, China. Dietary consumption was assessed by a valid self-administered FFQ. Principal component analysis was used to derive three major dietary patterns: ‘healthy’, ‘sweets’ and ‘traditional Tianjin’ from eighty-eight food items. Depressive symptoms were assessed using the Zung Self-Rating Depression Scale, and cut-off point of 48 indicating serious depressive symptoms. The association between quartile of dietary patterns and depressive symptoms was assessed using multiple logistic regression analysis. The multivariable-adjusted OR of having depressive symptoms for increasing quartile of dietary patterns were as follows: healthy, 1·00, 0·79 (95 % CI 0·49, 1·28), 0·62 (95 % CI 0·37, 1·04) and 0·57 (95 % CI 0·33, 0·97); sweets, 1·00, 0·75 (95 % CI 0·42, 1·3), 1·08 (95 % CI 0·64, 1·81) and 1·66 (95 % CI 1·03, 2·71); and traditional Tianjin, 1·00, 1·02 (95 % CI 0·58, 1·79), 0·96 (95 % CI 0·54, 1·71) and 2·53 (95 % CI 1·58, 4·16), respectively. The present study demonstrated that a healthy dietary pattern was inversely associated with depressive symptoms. On the contrary, greater adherence to sweets and traditional Tianjin dietary patterns was associated with a higher prevalence of depressive symptoms.
In this study, we investigate spray pyrolysis as an approach to synthesis of tunnel structure sodium manganese oxide, as it is a cost-effective and scalable technology. The powders synthesized with Na/Mn ratio of 0.50 displayed a pure tunnel structure, and demonstrated the best electrochemical performance, with a discharge capacity of 115 mAh/g. The material also showed good cycleability and rate capability. Noticeable decay in performance was seen in materials with Na/Mn ratios other than 0.50, indicating that this material is sensitive to minor compositional deviations. This study has demonstrated that spray pyrolysis is a promising synthesis method for this material.
Hypoxia is the primary stimulus for the production of erythropoietin (EPO) in both fetal and adult life. Here, we investigated fetal plasma EPO concentrations in monochorionic (MC) twin pregnancies with selective intrauterine growth restriction (sIUGR) and abnormal umbilical artery (UA) Doppler. We diagnosed sIUGR in presence of (1) birth-weight discordance >20% and (2) either twin with a birth weight <10th percentile. An abnormal UA Doppler was defined as a persistent absent-reverse end diastolic flow (AREDF). The intertwin EPO ratio was calculated as the plasma EPO level of the smaller (or small-for-gestational-age) twin divided by the EPO concentration of the larger (or appropriate-for-gestational-age (AGA)) twin. Thirty-two MC twin pairs were included. Of these, 17 pairs were normal twins (Group 1), seven pairs were twins with sIUGR without UA Doppler abnormalities (Group 2), and eight pairs were twins with sIUGR and UA Doppler abnormalities (Group 3). The highest EPO ratio was identified in Group 3 (p < .001) but no significant differences were observed between Groups 1 and 2. Fetal hemoglobin levels did not differ significantly in the three groups, and fetal EPO concentration did not correlate with gestational age at birth. We conclude that fetal plasma EPO concentrations are selectively increased in MC twin pregnancies with sIUGR and abnormal UA Doppler, possibly as a result of uncompensated hypoxia.
An abnormal central nervous system excitability level was found in patients with migraine. Whether it is hyper- or hypo-excitable is still debated. This study aimed to compare the somatosensory high-frequency oscillations (HFOs), which reflected subcortical excitability (early phase) and intracortical inhibition (late phase), between patients with migraine and control subjects.
Methods:
HFOs were recorded from C3'-Fz, using a 500-1000 Hz frequency filter after stimulation at right median nerves at the wrists, and divided into early and late phases based on the N20 peak. Fifty-nine untreated patients (n=24 during ictal period; n=35, interictal) and 22 controls finished the study.
Results:
In early HFOs, patients both during ictal and interictal periods had higher maximal amplitudes (p =0.039) and area-under-curve (p =0.029) than those of the controls. Regarding the late HFOs, there were no significant differences among these groups.
Conclusion:
Our study suggests a hyper-excitable state in the subcortical regions in patients with migraine both during interictal and ictal periods.
Nanoparticles of ∼55 nm in diameter have been found to significantly increase the fracture toughness of nanocomposites with a ductile polymer matrix. This paper presents a comparative study of the effectiveness of micrometer-sized and nanosized elastomeric particles in improving the fracture toughness and strength of polymeric adhesives. Particular focuses are on the effects of particle size, matrix ductility, and adhesive thickness on the shear strength and fracture toughness. The results reveal that for an epoxy adhesive cured with a J400 hardener, nanosized particles can produce nearly 18 times more increase in fracture toughness than what can be achieved using micrometer-sized particles at the same volume fraction of 5.0 vol%. This huge improvement of adhesives' fracture toughness by nanosized particles is similar to that observed in bulk nanocomposites, indicating that the superior toughening mechanism of nanosized elastomeric particles is equally effective in thin adhesives constrained by stiff adherends.
The potential relationship between anaesthesia, surgery and onset of
dementia remains elusive.
Aims
To determine whether the risk of dementia increases after surgery with
anaesthesia, and to evaluate possible associations among age, mode of
anaesthesia, type of surgery and risk of dementia.
Method
The study cohort comprised patients aged 50 years and older who were
anaesthetised for the first time since 1995 between 1 January 2004 and 31
December 2007, and a control group of randomly selected patients matched
for age and gender. Patients were followed until 31 December 2010 to
identify the emergence of dementia.
Results
Relative to the control group, patients who underwent anaesthesia and
surgery exhibited an increased risk of dementia (hazard ratio = 1.99) and
a reduced mean interval to dementia diagnosis. The risk of dementia
increased in patients who received intravenous or intramuscular
anaesthesia, regional anaesthesia and general anaesthesia.
Conclusions
The results of our nationwide, population-based study suggest that
patients who undergo anaesthesia and surgery may be at increased risk of
dementia.
In this article, we investigated the effect of Sn grain structure on the electromigration (EM) reliability of Sn–2.5Ag (wt%) solder joints used in flip-chip packages. The electron backscattering diffraction technique was applied to characterize the Sn grain size and orientation of the solder joints. Failure analyses on Sn–2.5Ag solder joints after EM tests showed that the Sn grain structure was important in controlling the kinetics of the intermetallic compound growth and void formation under EM. Further microstructural analysis revealed that the grain sizes and orientations of the solder joints after multiple solder reflows were statistically different from those with a single solder reflow and resulted in an improved EM reliability. Thermal annealing effect was also investigated to separate the thermal effect from the EM-induced effect. Results obtained in this study demonstrated that EM reliability of Pb-free solder joints could be improved by optimization of the Sn grain structure.
We used x-ray diffractometry (XRD), x-ray photoelectron spectrometry (XPS), and secondary-ion mass spectrometry (SIMS) to investigate the mechanism of the interfacial room-temperature (RT) chemical reaction between cation-deficient La0.56Li0.33TiO3 solid electrolytes and metallic lithium anodes in all-solid-state lithium batteries. A stoichiometric mixture of La2O3, Li2CO3, and TiO2 powders was calcined at 1250 °C for 8 h to obtain a single perovskite structure of La0.56Li0.33TiO3. When this La0.56Li0.33TiO3 sample and lithium were placed in contact at room temperature for 24 h, the phase of the La0.56Li0.33TiO3 remained unchanged. The XPS results indicate that 12% of the tetravalent Ti4+ ions were converted into trivalent Ti3+ ions. The valence conversion and degree of conversion were limited by the structural rigidity of the host crystal. Our SIMS analysis suggests the existence of a local electric field near the contact surface and indicates that the 6Li+ isotope ions were inserted into the specimen through the effect of this field. The change in the electrical properties of La0.56Li0.33TiO3 supports this mechanism for the interfacial reaction. The ionic conductivities of the grain and total grain boundary decreased and increased, respectively, after the insertion of Li+, and the total electronic conductivity increased as a result of the presence of intervalence electron hopping between mixed Ti3+/Ti4+ states. The mechanism of the lithium-activated RT interfacial reaction is associated with the reduction of Ti4+ transition metal ions from tetravalent to trivalent states and the local-electric-field-induced Li+ insertion into La3+/Li+-site vacancies of La0.56Li0.33TiO3.
A total of six amplified fragment length polymorphism (AFLP) primer combinations were used to detect genetic variation of pooled DNA in a sample of 12 chicken breeds indigenous to China, and AFLP DNA fingerprinting of each chicken breed was constructed. Polymorphic bands, specific bands and genetic similarity coefficients of 12 chicken breeds were calculated from AFLP data. A total of 279 polymorphic bands were generated by the six primer combinations, giving, on average, 46.5 polymorphic markers detected per primer combination. Nine specific bands were produced in the pooled DNA of Jiuyuan black and Dongxiang black chickens. However, one specific band was produced in the pooled DNA of Wenchang and Xingyi bantam chickens. An unweighted-pair-group method using average linkages (UPGMA) cluster analysis revealed that the 12 chicken breeds could be divided into three groups. Genetic similarity coefficients and the UPGMA tree of the 12 chicken breeds were consistent with their breeding history as well as their geographical distribution. Based on AFLP DNA fingerprinting, genetic diversity, genetic relationship and identification of chicken breeds can be analysed.
Objectives: To evaluate the applicability of the Chinese version of the Neuropsychiatric Inventory Scale (NPI), and to explore the neuropsychiatric manifestations of Taiwanese patients with Alzheimer's disease (AD) and caregiver distress. Method: The Mini-Mental State Examination (MMSE) was administered to 95 patients with AD, and their caregivers were interviewed with the NPI. To assess the test-retest reliability of the Chinese version of the NPI, 86 caregivers underwent a second NPI 3 weeks later. Results: The Cronbach's alpha coefficient of the Chinese version of the NPI was .76. The test-rest reliabilities of frequency, severity, and caregiver burden scores were significantly correlated; overall correlations were .85 for frequency (p < .001), .82 for severity (p < .001), and .79 (p < .001) for distress. Factor analysis was carried out, and three groups, “mood and psychosis,” “psychomotor regulation,” and “social engagement,” were found. Aberrant motor behavior was the most frequently recorded behavior; euphoria was the least. There was no significant correlation between the patient's MMSE and the caregiver distress score, except for aberrant motor activity (r = −.23, p = .03). The symptoms most frequently reported to be severely distressing to caregivers were aberrant motor activity, anxiety, agitation, and delusions. Conclusions: These results indicate that the NPI is a reliable tool to assess behavioral disturbance and caregiver distress in Taiwanese AD patients. These findings also confirm the high prevalence of psychopathology among AD patients and the marked distress produced by many of these behaviors.