[Clinical characteristics of perimenopausal female patients with rheumatoid arthritis].

Objective: To explore the menopause status of patients with rheumatoid arthritis (RA) and clinical characteristics of perimenopausal RA patients. Methods: A cross-sectional study. Female RA patients were recruited retrospectively in the Sun Yat-Sen Memorial Hospital from August 2015 to August 2023. Clinical data were collected, including onset age, disease duration, RA disease activity indicators, functional assessment, and radiographic scores. According to menopausal status, the patients were categorized as pre-menopausal, perimenopausal and post-menopausal groups to explore their menopausal and clinical characteristics. Results: A total of 1 151 female patients were enrolled, with a mean age of (50.2±13.0) years. At enrollment, there were 470 (40.8%), 140 (12.2%) and 541 (47.0%) patients in pre-menopause, perimenopause and post-menopause status, respectively. The mean age of menopause was (49.0±4.2) years. Compared with pre-menopausal group, perimenopausal RA patients had higher disease activity indicators [clinical disease activity index (CDAI) 17 (6, 26) vs 10 (3, 19) ], higher levels of inflammation [erythrocyte sedimentation rate (ESR) 35 (21, 65) vs 26 (14, 44) mm/1h, C-reactive protein (CRP) 6.2 (3.2, 16.8) vs 3.3 (3.2, 13.6) mg/L], and a higher proportion of functional limitation [25.0%(35/140) vs 10.4%(49/470)] (all P<0.016 7); while there was no significant differences in disease activity[M(Q1, Q3)] [CDAI 17 (6, 26) vs 14 (6, 25)], levels of inflammation [ESR 35(21, 65) vs 42 (23, 72) mm/1h, CRP 6.2 (3.2, 16.8) vs 6.2 (3.3, 23.9) mg/L] and functional limitation [25.0%(35/140) vs 28.8%(156/541)] when compared with those in post-menopausal group (all P>0.016 7). In RA patients during the perimenopausal period, 49 cases (35.0%) developed RA during this period. Compared with patients with RA onset during reproductive age, patients with RA onset during the perimenopausal period had higher numbers of 28-joint tender joints [7 (2, 10) vs 4 (0, 8)], higher CDAI [20 (12, 29) vs 14 (4, 24)], and higher ESR [45 (25, 72) vs 32 (18, 56) mm/1h] (all P<0.05). Conclusion: Perimenopausal patients with RA have severe disease activity and functional limitation.

[Hepatitis B virus infection status and clinical characteristics in patients with rheumatoid arthritis].

Objective: To investigate the epidemiology of hepatitis B virus (HBV) infection in patients with rheumatoid arthritis (RA) in China and its association with RA disease characteristics. Methods: A cross-sectional study. A retrospective study was conducted on RA patients recruited from January 2001 to February 2023 in the Department of Rheumatology and Immunology, Sun Yat-Sen Memorial Hospital. Demographic and clinical data were collected including age, gender, disease duration, active smoking, RA disease activity, physical function, radiographic assessment, serological markers of HBV infection and liver function indicators. According to the status of HBV infection, RA patients were grouped as chronic HBV infection, resolved HBV infection and no HBV infection groups. The distribution of each group and the clinical characteristics of RA patients were analyzed. Results: Among 1 941 RA patients, 1 461 (75.3%) completed HBV screening, including 335 males (22.9%) and 1 126 females (77.1%), with a mean age of (55.4±13.1) years. The prevalence of chronic HBV infection was 10.1%(148/1 461), which was significantly higher in male patients than in females [14.6%(49/335) vs 8.8%(99/1 126), P<0.001], especially among those males born from 1970 to 1979[20.0%(7/35) vs 8.5%(17/201), P=0.037] and 1980-1989 [31.8%(7/22) vs 10.5%(14/133), P=0.007]. Among 148 RA patients with chronic HBV infection, there were 5 cases (3.4%) of chronic hepatitis B, 2 cases (1.4%) of HBV-associated cirrhosis and 1 case (0.7%) of hepatocellular carcinoma. The prevalence of resolved HBV infection was 57.6%(841/1 461). There were 472(32.3%) patients with no HBV infection and 267(56.6%) of them showed negative anti-HBs. Among all RA patients, 15 (1.0%) patients had abnormal liver function, of which 7 cases were drug-induced liver injury, 5 cases were chronic hepatitis B, 2 cases were non-alcoholic fatty liver disease, and 1 case was primary biliary cholangitis. Conclusion: Chronic HBV infection remains a common complication in RA patients in China, the infection rate is 10.1%, and the screening and management of HBV infection should be strengthened in clinical practice.

High-field magnetization and electronic spin resonance study in the twisted honeycomb latticeα-Mn2V2O7.

We report the single-crystal growth of Mn2V2O7and the results of magnetic susceptibility, high-field magnetization up to 55 T and high-frequency electric spin resonance (ESR) measurements for its low-temperatureαphase. Two antiferromagnetic (AFM) ordering at 17.5 K and 3 K and obvious magnetic anisotropy are observed inα-Mn2V2O7upon cooling. In pulsed high magnetic fields, the compound reaches the saturation magnetic moment of ∼10.5µBfor each molecular formula at around 45 T after two undergoing AFM phase transitions atHc1≈ 16 T,Hc2≈ 34.5 T forH//[11-0] andHsf1= 2.5 T,Hsf2= 7 T forH//[001]. In these two directions, two and seven resonance modes are detected by ESR spectroscopy, respectively. Theω1andω2modes ofH//[11-0] can be well described by two-sublattice AFM resonance mode with two zero-field gaps at 94.51 GHz and 169.28 GHz, indicating a hard-axis feature. The seven modes forH//[001] are partially separated by the critical fields ofHsf1andHsf2, displaying the two signs of spin-flop transition. The fittings ofωc1andωc2modes yield zero-field gaps at 69.50 GHz and 84.73 GHz forH//[001], confirming the axis-type anisotropy. The saturated moment and gyromagnetic ratio indicate the Mn2+ion inα-Mn2V2O7is in a high spin state with orbital moment completely quenched. A quasi-one-dimensional magnetism with a zig-zag-chain spin configuration is suggested inα-Mn2V2O7, due to the special neighbor interactions caused by a distorted network structure with honeycomb layer.

[Immune checkpoint inhibitor-induced eosinophilic fasciitis: a case report and literature review].

A 58-year-old male patient with angioimmunoblastic T-cell lymphoma developed a rash and skin tightness on the face, limbs, and trunk together with joint stiffness and dysfunction after 6 months of treatment with the programmed cell death protein-1 inhibitor camrelizumab. Laboratory tests revealed progressive eosinophilia over 6 months, with the eosinophil count increasing from 0.07×109/L to 3.3×109/L. Magnetic resonance imaging showed thickened skin of both forearms, while T2-weighted imaging showed markedly increased signal intensity within the myofascia. Skin biopsy of the right forearm showed thickened and fibrosed fascia and infiltration of inflammatory cells, including lymphocytes, plasma cells, and eosinophils. The patient was diagnosed with immune checkpoint inhibitor (ICI)-induced eosinophilic fasciitis (EF). After beginning treatment with methylprednisolone (40 mg daily), methotrexate (10 mg/week), and baricitinib (4 mg daily), his symptoms of skin tightness and joint dysfunction significantly improved within 1 month, and his peripheral blood eosinophil count decreased to 0.17×109/L. ICI-induced EF is a rare immune-related adverse reaction. To date, only 20 cases have been reported in published foreign literature, and their clinical characteristics are summarized here. The time from ICI treatment to EF was 12 (8,15) months, and the main clinical manifestations included skin involvement (n=19), joint dysfunction (n=11), myalgia/muscle weakness (n=9), and peripheral eosinophilia (n=16). After treatment, the clinical symptoms of EF improved in 17 patients, and eosinophil counts returned to normal after 3 (1,8) months. EF is a dysfunctional adverse response to ICI therapy. Tumor patients undergoing immunotherapy should be monitored for symptoms of EF. Early treatment is essential for preventing complications.

Risk factors for Clostridioides difficile infection in children: a systematic review and meta-analysis.

BACKGROUND: Clostridioides difficile is considered an urgent threat to human health by the US Centers for Disease Control and Prevention. In recent years, C. difficile has been reported increasingly as a cause of gastrointestinal disease in children, and the prevalence of hospital-acquired C. difficile infection and community-acquired CDI in children is increasing. AIM: To perform a systematic review and meta-analysis of risk factors for CDI in children. METHODS: MEDLINE/PubMed, EMBASE, Web of Science, Scopus, OVID, China National Knowledge Infrastructure, Wanfang (Chinese), SinoMed (Chinese) and Weipu (Chinese) were searched from inception to 12th January 2022. Observational studies (cohort, case-control and cross-sectional) on CDI in children were included in the analysis. Data were pooled using a fixed or random-effects model, and odds ratios (OR) were calculated. FINDINGS: In total, 25 observational studies were included in the analysis. Prior antibiotic exposure [OR 1.93, 95% confidence interval (CI) 1.25-2.97], prolonged hospitalization (OR 14.68, 95% CI 13.24-16.28), history of hospitalization (OR 3.67, 95% CI 1.91-7.06), gastric acid suppressants (OR 1.96, 95% CI 1.41-2.73), male gender (OR 1.18, 95% CI 1.05-1.32), neoplastic disease (OR 3.40, 95% CI, 2.85-4.07), immunodeficiency (OR 4.18, 95% CI 3.25-5.37), solid organ transplantation (OR 4.56, 95% CI 3.95-5.27) and enteral feeding (OR 2.21, 95% CI 1.05-4.62) were associated with increased risk of CDI. CONCLUSION: This systematic review and meta-analysis provides further evidence for the susceptibility factors of CDI to improve clinicians' awareness of CDI, and prevent C. difficile-associated diarrhoea in children.

Angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br.

We report angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br by angle-dependent magnetization and ESR measurements. The results show that the antiferromagnetic easy magnetization axis is the diagonal direction (θ= 45°) of theac*plane, i.e., the orientation of Cu1 spins based on the magnetic structure (2020Phys. Rev. Lett.125037204), whereas the spin-flop axis is thebaxis. A phenomenological model is proposed to describe the angle-dependent spin-flop transitions. Based on this model, Cu1 spins are sensitive to external magnetic field, while Cu2 spins are robust against to the field, showing partial decoupling. The model is expected to be used in other uniaxial antiferromagnets with a more general easy axis and complex spin-flop transitions.

Speed determinacy of travelling waves for a three-component lattice Lotka-Volterra competition system.

In this paper, the invasive speed selection of the monostable travelling wave for a three-component lattice Lotka-Volterra competition system is studied via the upper and lower solution method, as well as the comparison principle. By constructing several special upper and lower solutions, we establish sufficient conditions such that the linear or nonlinear selection is realized.

Characterizing the impact of high temperature during grain filling on phytohormone levels, enzyme activity and metabolic profiles of an early indica rice variety.

Global warming results in high temperature stress (HTS), which presents severe challenges worldwide for modern agricultural production and will have significant impacts on the yield and quality of crops. Accumulation of photosynthetic products, activity of enzymes involved in sucrose-starch metabolism, phytohormone levels and metabolic profiling using LC-MS were analysed in the flag leaves and/or developing grains subjected to HTS during the grain-filling stage of an indica rice. HTS induced significant yield loss and reduced the grain quality, with lower amylose content. HTS reduced photosynthetic product accumulation in flag leaves and reduced starch accumulation in developing grains, compared to growth under normal temperatures. The activity of enzymes related to sucrose-starch metabolism were dis-regulated in developing grains grown under high temperature (HT). Moreover, phytohormone homeostasis in flag leaves and developing grains was also dramatically disturbed by HT. Metabolic profiling detected many metabolites with remarkably different relative fold abundances at different time points in the developing grain at HT versus normal temperatures, these metabolites were enriched in several HTS response pathways. The change in phytohormone ratio and auxin level might be associated with the reduction in photosynthetic products and their translocation, and ultimately with reduced starch accumulation in the developing grain. The detected metabolites might have different roles in response to the HTS in developing grain at different development stages. These results provide a theoretical reference and basis for future rice production towards higher quality and yield when grown under HTS.

Field-induced magnetic transitions and strong anisotropy in α-CoV2O6 single crystal.

The Ising-like antiferromagnet α-CoV2O6 has received considerable interests because of stabilized 1/3 magnetization plateau around 5 K under magnetic field applied along magnetic easy c-axis. In this work, this magnetization plateau was studied by varying temperature or rotating magnetic field. As temperature decreased, this stabilized plateau collapsed, and additional magnetic transitions were observed. As a result, a rich magnetic phase diagram was constructed and extended to temperature lower than previously reported. When magnetic field moved from the c to b (or a) axis, the magnetization plateau developed with field directions and vanished finally when the field was restricted in the ab plane. An impressive observation is that this 1/3-plateau can be stabilized and remain robust even when magnetic field deviated from the c axis, accompanied by the evolutions of the magnetic moments and the critical transition fields. We suppose that the origins of these temperature and angular dependences of the 1/3 magnetization plateau are related to strong spin-orbital coupling. Indeed, electron spin resonance (ESR) measurement gives large Landé factor of 8.9, evidencing that there exists strong spin-orbital coupling.

[Influence of family integrated care on the intestinal microbiome of preterm infants in the neonatal intensive care unit].

Objective: To investigate the influence of family integrated care (FICare) on the intestinal microbiome of preterm infants in neonatal intensive care unit (NICU). Methods: This was a prospective observational pilot study. A total of 44 preterm infants (23 boys, 52%) admitted to NICU of the Third Xiangya Hospital of Central South University from July, 2015 to June, 2017 were enrolled and divided into FICare, non-FICare groups. Totally 20 term infants (11 boys, 55%) were enrolled into control group, who were sent to the Pediatric Healthcare Clinic for regular health check on postnatal 28-31 days. All infants were free from probiotics after birth and on full enteral feeding. Clinical data of all infants were collected. Two fresh stool specimens of infants in FICare group were collected after 2 weeks of FICare implementation, without use of antibiotics during the prior 1 week. Stool specimens of infants in non-FICare group were collected at the meantime;while for the infants in control group, stool samples were collected at 4 weeks of age. All specimens were stored in-80 ℃ freezer, subsequently investigated by 16 S rRNA sequencing. The results were filtered by paired-end reads software based on RNA overlapping-splicing and tags calculation. Operational taxonomic units (OTU) were analyzed for intestinal microbiome richness. Intestinal microbiome diversity was measured with Shannon index. One-way ANOVA or Kruskal-Wallis H statistic analysis or Chi-square test was used for statistical analysis. Results: There were no significant differences among FICare, non-FICare and control groups in male proportion (52% (11/21) vs. 52% (12/23) vs. 55% (11/20), χ(2)=0.041, P=0.980), in-born ratio (90% (19/21) vs. 87% (20/23) vs. 85% (17/20), χ(2)=0.000, P=1.000), and percentage of infants with Apgar scores<7 at 5 minutes after birth (14% (3/21) vs. 9% (2/23) vs. 5% (1/20), χ(2)=0.120, P=0.729). Similarly, no significant differences were found between FICare and non-FICare groups in terms of gestational age ((29.7±1.8) vs. (29.9±1.7) weeks, t=0.378, P=0.707), birth weight ((1 266±310) vs. (1 326±318) g, t=0.631, P=0.531), median age of initiating feeds (4 vs. 4 days old, Z=0.666, P=0.505), and median age of achieving feeding volume of 120 ml/(kg·d)(13 vs. 11 days old, Z=1.014, P=0.310). However, the breast-feeding rate in FICare group (18/21, 86%) was significantly higher than that in non-FICare group (8/23, 35%) (t=11.780, P=0.001). The medium Shannon index was 0.72 (0.27,2.66), 0.61 (0.18,1.83), and 0.52 (0.08,1.71) in control, FICare, and non-FICare groups, respectively, without significant difference (H=1.823, P=0.402). The domain flora was Lactobacillus Firmicutes in all three groups, which was of the highest percentage in FICare group (71.6±5.4)%, followed by control group (65.4±6.6)% and non-FICare group (55.6±8.8)%, with a significant difference (F=27.919, P=0.000). Conclusions: FICare can improve the richness and diversity of intestinal microbiome, stimulate the establishment of flora close to those of normal breast-feeding infants in preemies in NICU, making its establishment being more similar to normal term breast-feeding infants. This effect might be caused by the increased skin-to-skin contact and increased fresh breast-milk-feeding in FICare.

[Analysis of the entrance and suture method of umbilical incision in gynecological laparoscopy].

Objective: To explore the entrance and suture method of umbilical incision in gynecological laparoscopy. Methods: A total of 204 cases of gynecologic laparoscopy in our hospital from 2013 to 2016 were reviewed respectively. All the cases used two kinds of approach of umbilical incision: intra-umbilical incision and peri-umbilical incision (longitudinal/transverse oblique/arc incision according to the bellybutton natural skin folds) and two methods of suture: the suture of "U" and the suture of the whole subcutaneous tissue. Two groups were randomly assigned based on the entrance and suture method with each group 102 cases. The peri-operative outcomes were compared, including intra-operative and postoperative bleeding, postoperative incision fat liquefaction and infection, incision pain, incision appearance satisfaction and incision healing satisfaction. Results: The difference was statistically significant in the intra-operative and postoperative bleeding between two groups of intra-umbilical incision and peri-umbilical incision (P<0.05). There was statistically significant difference in postoperative incision fat liquefaction, infection and incision pain between two groups of the suture of "U" and the suture of the whole subcutaneous tissue (P<0.05). The incision appearance satisfaction showed no difference (P>0.05), but the difference was statistically significant (P<0.05) in the incision healing satisfaction between two groups. Conclusion: The peri-umbilical incision (longitudinal/transverse oblique/arc incision according to the bellybutton natural skin folds) and suture of the whole subcutaneous tissue can be the feasible modified methods with high practicability and security, good cosmetic result. It should be promoted in gynecologic laparoscopy.

[The expressions and the roles of SDF-1/CXCR-4 and SDF-1/CXCR-4 in human endometriosis].

Objective: To investigate the expressions and significances of SDF-1 and its receptor CXCR-4 in endometriosis. Methods: 50 hysteromyoma patients treated at Beijing Tongren Hospital, Capital Medical University between 1(st) January 2016 and 31(st) December 2017 were divided into control group, that is, non-endometriosis group, while another 50 endometriosis patients were divided into experimental group.The endometrial tissues, endometriosis lesions, and peritoneal fluid samples of hysteromyoma patients were collected by operation.RT-PCR, ELISA and immunohistochemistry were adopted to detect the expressions of SDF-1 and CXCR-4 in the two groups.Cell count was used to analyze the roles of SDF-1 and CXCR4 in the mitosis and proliferation of endometrial stromal cells. Results: The mean value of SDF-1 and CXCR-4 expressions in ascites or peritoneal fluid of endometriosis patients were (2.56±0.33) mg/L and (4.47±0.32) mg/L, respectively. The mean concentrations in ascites or peritoneal fluid in hysteromyoma patients were (1.39±0.36) mg/L and (3.16±0.32) mg/L, respectively.The expressions of SDF-1 and CXCR-4 in ascites or peritoneal fluid of endometriosis patients were both significantly higher than those of patients in non-endometriosis group (P<0.05). SDF-1 and CXCR-4 were expressed in both endometriosis lesions and the glandular epithelial cells and mesenchymal cells of normal endometrial tissue.Positive staining sites were located in the cytoplasm.A value was used to calculate and analyze the expression of immune staining.The mean A value of SDF-1 and CXCR-4 in endometriosis group were 0.21±0.13 and 0.21±0.13, respectively, and the mean A value in normal endometrial tissues were 0.15±0.13 and 0.14±0.13, respectively.The expressions of these two in endometrial tissues were significantly higher than that in normal endometrial tissues, and the differences were statistically significant (P<0.05). The expression of CXCR-4 mRNA was abundant in the mesenchymal cells of endometriosis cultured in vitro.SDF-1 promoted the mitosis and proliferation of endometrial stromal cells cultured in vitro in a dose-dependent manner.The neutralizing antibody against CXCR-4 was obviously inhibited. Conclusion: The high expressions of SDF-1 and CXCR-4 in endometriosis as well as SDF-1 through its specific receptor CXCR-4 promoted the mitosis and proliferation of endometrial stromal cells, suggesting that SDF-1 and CXCR-4 played important roles in the pathogenesis of endometriosis.

Genome-wide DNA methylation profiling reveals cancer-associated changes within early colonic neoplasia.

Colorectal cancer (CRC) is characterized by genome-wide alterations to DNA methylation that influence gene expression and genomic stability. Less is known about the extent to which methylation is disrupted in the earliest stages of CRC development. In this study, we have combined laser-capture microdissection with reduced representation bisulfite sequencing to identify cancer-associated DNA methylation changes in human aberrant crypt foci (ACF), the earliest putative precursor to CRC. Using this approach, methylation profiles have been generated for 10 KRAS-mutant ACF and 10 CRCs harboring a KRAS mutation, as well as matched samples of normal mucosa. Of 811 differentially methylated regions (DMRs) identified in ACF, 537 (66%) were hypermethylated and 274 (34%) were hypomethylated. DMRs located within intergenic regions were heavily enriched for AP-1 transcription factor binding sites and were frequently hypomethylated. Furthermore, gene ontology analysis demonstrated that DMRs associated with promoters were enriched for genes involved in intestinal development, including homeobox genes and targets of the Polycomb repressive complex 2. Consistent with their role in the earliest stages of colonic neoplasia, 75% of the loci harboring methylation changes in ACF were also altered in CRC samples, though the magnitude of change at these sites was lesser in ACF. Although aberrant promoter methylation was associated with altered gene expression in CRC, this was not the case in ACF, suggesting the insufficiency of methylation changes to modulate gene expression in early colonic neoplasia. Altogether, these data demonstrate that DNA methylation changes, including significant hypermethylation, occur more frequently in early colonic neoplasia than previously believed, and identify epigenomic features of ACF that may provide new targets for cancer chemoprevention or lead to the development of new biomarkers for CRC risk.

Size reduction-induced chain breaking in Haldane-chain compounds SrNi2-x Mg x V2O8 (x = 0 and 0.1).

We report size reduction-induced chain breaking in the spin-1 Haldane-chain SrNi2-x Mg x V2O8 (x = 0 and 0.1) by magnetization and electron spin resonance measurements. For x = 0.0, the magnetic susceptibility of all samples can be well described by a temperature-independent term, a Curie-Weiss term and a Haldane-gap term. This implies that a reduced sample grain size breaks the long chain and creates a considerable number of S = 1/2 edge spins, resulting in the enhancement of magnetization and the decrease of Haldane gap in the samples. These edge spins as well as the other paramagnetic ions at grain boundary and surface might be weakly coupled with each other. For the Mg-doped sample with x = 0.1, there are more S = 1/2 spins creased in relative to x = 0.0 because of a combined effect of lattice defects, Mg-doping and reduced size. In addition, the antiferromagnetic resonance of x = 0.1 is also presented.

3D spin-flop transition in enhanced 2D layered structure single crystalline TlCo2Se2.

The enhanced 2D layered structure single crystalline TlCo2Se2 has been successfully fabricated, which exhibits field-induced 3D spin-flop phase transitions. In the case of the magnetic field parallel to the c-axis (B//c), the applied magnetic field induces the evolution of the noncollinear helical magnetic coupling into a ferromagnetic (FM) state with all the magnetization of the Co ion parallel to the c-axis. A striking variation of the field-induced strain within the ab-plane is noticed in the magnetic field region of 20-30 T. In the case of the magnetic field perpendicular to the c-axis (B ⊥ c), the inter-layer helical antiferromagnetic (AFM) coupling may transform to an initial canted AFM coupling, and then part of it transforms to an intermediate metamagnetic phase with the alignment of two-up-one-down Co magnetic moments and finally to an ultimate FM coupling in higher magnetic fields. The robust noncollinear AFM magnetic coupling is completely destroyed above 30 T. In combination with the measurements of magnetization, magnetoresistance and field-induced strain, a complete magnetic phase diagram of the TlCo2Se2 single crystal has been depicted, demonstrating complex magnetic structures even though the crystal geometry itself gives no indication of the magnetic frustration.

Chemical profiling of cerebrospinal fluid by multiple reaction monitoring mass spectrometry.

We report an accelerated biomarker discovery workflow and results of sample screening by mass spectrometry based on multiple reaction monitoring (MRM). This methodology shows promising initial results for the currently unsolved challenge of Parkinson's disease (PD) laboratory diagnosis by biomarker screening. Small molecules present in cerebrospinal fluid (CSF) at low parts per million levels are monitored using specific transitions connecting ion pairs. A set of such transitions constitutes a multidimensional chemical profile used to distinguish and characterize different CSF samples using multivariate statistical methods.

A compact, all-optical, THz wave generator based on self-modulation in a slab photonic crystal waveguide with a single sub-nanometer graphene layer.

We design a compact, all-optical THz wave generator based on self-modulation in a 1-D slab photonic crystal (PhC) waveguide with a single sub-nanometer graphene layer by using enhanced nonlinearity of graphene. It has been shown that at the bandgap edge of higher bands of a 1-D slab PhC, through only one sub-nanometer graphene layer we can obtain a compact, high modulation factor (about 0.98 percent), self-intensity modulator at a high frequency (about 0.6 THz) and low threshold intensity (about 15 MW per square centimeter), and further a compact, all-optical THz wave generator by integrating the self-modulator with a THz photodiode or photonic mixer. Such a THz source is expected to have a relatively high efficiency compared with conventional sources based on optical methods. The proposed THz source can find wide applications in THz science and technology, e.g., in THz imaging, THz sensors and detectors, THz communication systems, and THz optical integrated logic circuits.

Slow magnetic relaxation in mononuclear seven-coordinate cobalt(II) complexes with easy plane anisotropy.

Two mononuclear seven-coordinate cobalt(II) complexes [Co(L)3(NO3)2] (L = 4-tert-butylpyridine, 1; L = isoquinoline, 2) were prepared and structurally analyzed by single-crystal X-ray crystallography. The coordination spheres of 1 and 2 exhibit distorted pentagonal bipyramid geometry. Analysis of their direct-current magnetic data reveals the existence of easy plane anisotropy (D > 0) with a small transverse anisotropy (E), which was further confirmed by high-field electron paramagnetic resonance (HFEPR) spectroscopy. Field-induced slow magnetic relaxations were observed under the applied dc field in complexes 1 and 2 by alternating-current magnetic susceptibility measurements. Importantly, these complexes are new instances of mononuclear high-coordinate cobalt(II)-based single-molecule magnets.

Association between loop diuretic use and fracture risk.

SUMMARY: Loop diuretic use has been shown to be associated with an increased fracture risk, but the findings have been inconsistent. The present meta-analysis suggests that loop diuretics show a significant positive association with the overall risk of total fractures and, specifically, hip fractures. INTRODUCTION: Despite being widely used, there is limited, prospective randomized trial evidence regarding the skeletal effects of loop diuretics. Previous observational studies have reported conflicting findings regarding the association between loop diuretic use and the risk of fractures. METHODS: This meta-analysis of observational studies assessed the association between loop diuretic use and the risk of fractures. The PubMed, EMBASE, and OVID databases were searched for prospective cohort and case-control studies. Relative risks (RR) with 95% confidence intervals (CI) were derived using random-effects models throughout the analysis. RESULTS: Thirteen studies (4 cohort studies and 9 case-control studies) were included, involving 842,644 participants and 108,247 fracture cases. Compared with non-users, people who had taken loop diuretics had an approximately 15% higher risk of total fractures (95% CI, 1.04-1.26; p<0.01), with high heterogeneity between studies (I2=80.5%; p<0.01). The RR was 1.14 (95% CI, 1.08-1.19) for hip fractures and 0.99 (95% CI, 0.93-1.05) for lower arm or wrist fractures. The RR was 1.05 (95% CI, 1.00-1.11) in prospective cohort studies and 1.22 (95% CI, 1.00-1.44) in case-control studies. There was no evidence of publication bias. CONCLUSION: The results suggest that loop diuretics show a significant positive association with the overall risk of total fractures and hip fractures.