Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.

Pyrosequencing Analysis of Subgingival Microbiota in Distinct Periodontal Conditions

Subgingival microorganisms are potentially associated with periodontal diseases. However, changes in the subgingival microbiota during the progress of periodontal diseases are poorly understood. In this study, we analyzed bacterial communities in the subgingival paper point samples from 32 Korean individuals with no sign of disease, gingivitis, or periodontitis using 454 FLX Titanium pyrosequencing. A total of 256,113 reads representing 26 phyla, 433 genera, and 1,016 species were detected. Bacteroidetes, Fusobacteria, Synergistetes, and Spirochaetes were the abundant phyla in periodontitis subjects, whereas Firmicutes and Proteobacteria were identified as the dominant phyla in the gingivitis and healthy subjects, respectively. Although high levels of Porphyromonas, Fusobacterium, Fretibacterium, Rothia, Filifactor, and Treponema genera were observed in the periodontitis subjects, Streptococcus, Capnocytophaga, Leptotrichia, and Haemophilus genera were found at high frequency in the gingivitis subjects. Species including Porphyromonas gingivalis, Fusobacterium nucleatum, and Fretibacterium fastidiosum were significantly increased in periodontitis subjects. On the other hand, Streptococcus pseudopneumoniae, Haemophilus parainfluenzae, and Leptotrichia hongkongensis were preferentially observed in the gingivitis subjects. Intriguingly, the halophile Halomonas hamiltonii was revealed as a predominant species in the healthy subjects. Based on Fast UniFrac analysis, distinctive bacterial clusters were classified for the healthy, gingivitis, and periodontitis state. The current findings might be useful for understanding the pathogenesis, diagnosis, and treatment of periodontal diseases.

Fluoxetine and S-citalopram inhibit M1 activation and promote M2 activation of microglia in vitro

Increasing evidence has suggested that microglia dysfunction plays an important role in the pathogenesis of depression. Both classical activation (M1 activation) and alternative activation (M2 activation) may be involved in the process. M1-activated microglia secrete various pro-inflammatory cytokines and neurotoxic mediators, which may contribute to the development of depression, while M2-activated microglia promote tissue reconstruction by releasing anti-inflammatory cytokines involved in the process of depression. Selective serotonin reuptake inhibitors (SSRIs) are first-line treatments for depression, and their effects on immune system modulation have recently gained attention. Several studies have suggested that SSRIs affect the M1 activation of microglia, but results have varied. In addition, little is known about the effect of SSRIs on M2 activation in depression. The aim of this study was to investigate the effects of fluoxetine and S-citalopram, two widely used SSRIs in clinical, on both the M1 and M2 activation of microglia (the murine BV2 cell line and mouse primary microglia cell). The indexes of activation were measured by real-time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA) and Western blot. The present results showed that both fluoxetine and S-citalopram significantly down-regulated the indexes of M1 activation and up-regulated the M2 activation indexes on mRNA and protein levels either in cell line or primary cells. Taken together, the results suggested that fluoxetine and S-citalopram modulated the immune system by inhibiting M1 activation and by improving M2 activation of microglia and that the immune system modulation may partially mediate the therapeutic effects of antidepressant drugs-SSRIs.

Precision Measurement of the (e^{+}+e^{-}) Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station

We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e^{+}+e^{-}) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale).

Evaluation of a 2-channel portable device and a predictive model to screen for obstructive sleep apnea in a laboratory environment

BACKGROUND

Various portable monitors for identifying obstructive sleep apnea (OSA) have been investigated and reported to enable accurate recording of OSA severity. However, more information is needed from different populations. This study was conducted to evaluate the efficiency of a portable 2-channel sleep apnea device (SleepView) for screening OSA in the Chinese population.

METHODS

Ninety-three consecutive subjects underwent simultaneous SleepView testing and laboratory polysomnography (PSG) monitoring. Data were collected and blindly analyzed. The efficiency of the SleepView device and a newly established predictive model for identifying OSA was evaluated in comparison with PSG.

RESULTS

Good agreement was evident between the SleepView and PSG based on the apnea-hypopnea index (AHI; r(2) = 0.84, P < .01). The median AHI yielded by the SleepView was higher than that of PSG: 33.2 (interquartile range of 10.5-53.3) versus 19.2 (interquartile range of 5.2-53.6). The sensitivity and specificity of the SleepView for a PSG AHI of ≥ 5 were 80.28% and 95.45%, respectively, and the cutoff was 16.8. The area under the receiver operating curve for PSG AHIs of ≥ 5, > 15, and > 30 was 0.923, 0.924, and 0.979, respectively. When the AHI and oxygen desaturation index calculated by the SleepView were combined with waist circumference, the new predictive model showed a higher sensitivity of 92.96% and a specificity of 95.45% for a PSG AHI of ≥ 5, and the corresponding area under the receiver operating curve was 0.983.

CONCLUSIONS

The SleepView device exhibited acceptable diagnostic accuracy for OSA in the Chinese population, especially in the severe OSA group. A practical predictive model comprising waist circumference, AHI, and oxygen desaturation index obtained with the SleepView was highly effective for screening even mild OSA. This simple and practical device may serve as a useful tool to screen for OSA. Further studies are required to validate the diagnostic efficiency of the SleepView in the home environment and in different populations.

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station

A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy.

Respiratory syncytial virus prophylaxis in Down syndrome: a prospective cohort study

BACKGROUND AND OBJECTIVES

Children with Down syndrome (DS) are at significant risk for respiratory syncytial virus (RSV) infection and related hospitalization. We compared hospitalization rates due to respiratory tract infection in children with DS aged <2 years who prospectively received palivizumab during the RSV season with a previously published, similar untreated DS birth cohort.

METHODS

A total of 532 children with DS who prospectively received palivizumab were assembled from the prospective Canadian RSV Evaluation Study of Palivizumab registry between 2005 and 2012. The untreated group included 233 children with DS derived from a nationwide Dutch birth cohort from 2003 to 2005. Events during the RSV seasons were counted. Poisson regression analysis was performed to compare incidence rate ratios (95% confidence intervals [CIs]) between groups while controlling for observation length and known risk factors for severe RSV infection.

RESULTS

In total, 31 (23 untreated, 8 treated) RSV-related hospitalizations were documented. The adjusted risk of RSV-related hospitalizations was higher in untreated subjects than in palivizumab recipients (incidence rate ratio 3.63; 95% CI, 1.52-8.67). The adjusted risk of hospitalization for all respiratory tract infection (147 events; 73 untreated, 74 treated) was similar (incidence rate ratio untreated versus palivizumab 1.11; 95% CI, 0.80-1.55).

CONCLUSIONS

These results suggest that palivizumab is associated with a 3.6-fold reduction in the incidence rate ratio for RSV-related hospitalization in children with DS during the first 2 years of life. A randomized trial is needed to determine the efficacy of RSV immunoprophylaxis in this specific high-risk patient population.

Fenton Oxidation Kinetics and Intermediates of Nonylphenol Ethoxylates

Removal of nonylphenol ethoxylates (NPEOs) in aqueous solution by Fenton oxidation process was studied in a laboratory-scale batch reactor. Operating parameters, including initial pH temperature, hydrogen peroxide, and ferrous ion dosage, were thoroughly investigated. Maximum NPEOs reduction of 84% was achieved within 6 min, under an initial pH of 3.0, 25°C, an H₂O₂ dosage of 9.74×10^-3 M, and a molar ratio of [H₂O₂]/[Fe²⁺] of 3. A modified pseudo-first-order kinetic model was found to well represent experimental results. Correlations of reaction rate constants and operational parameters were established based on experimental data. Results indicated that the Fenton oxidation rate and removal efficiency were more dependent on the dosage of H₂O₂ than Fe²⁺, and the apparent activation energy (ΔE) was 17.5 kJ/mol. High-performance liquid chromatography and gas chromatograph mass spectrometer analytical results indicated degradation of NPEOs obtained within the first 2 min stepwise occurred by ethoxyl (EO) unit shortening. Long-chain NPEOs mixture demonstrated a higher degradation rate than shorter-chain ones. Nonylphenol (NP), short-chain NPEOs, and NP carboxyethoxylates were identified as the primary intermediates, which were mostly further degraded.

The novel miR-9500 regulates the proliferation and migration of human lung cancer cells by targeting Akt1

MicroRNAs have crucial roles in lung cancer cell development. They regulate cell growth, proliferation and migration by mediating the expression of tumor suppressor genes and oncogenes. We identified and characterized the novel miR-9500 in human lung cancer cells. The miR-9500 forms a stem-loop structure and is conserved in other mammals. The expression levels of miR-9500 were reduced in lung cancer cells and lung cancer tissues compared with normal tissues, as verified by TaqMan miRNA assays. It was confirmed that the putative target gene, Akt1, was directly suppressed by miR-9500, as demonstrated by a luciferase reporter assay. The miR-9500 significantly repressed the protein expression levels of Akt1, as demonstrated via western blot, but did not affect the corresponding mRNA levels. Akt1 has an important role in lung carcinogenesis, and depletion of Akt1 has been shown to have antiproliferative and anti-migratory effects in previous studies. In the current study, the overexpression of miR-9500 inhibited cell proliferation and the expression of cell cycle-related proteins. Likewise, the overexpression of miR-9500 impeded cell migration in human lung cancer cells. In an in vivo assay, miR-9500 significantly suppressed Fluc expression compared with NC and ASO-miR-9500, suggesting that cell proliferation was inhibited in nude mice. Likewise, miR-9500 repressed tumorigenesis and metastasis by targeting Akt1. These data indicate that miR-9500 might be applicable for lung cancer therapy.

Hospitalization for respiratory syncytial virus illness in Down syndrome following prophylaxis with palivizumab

BACKGROUND

Down syndrome (DS) is a risk factor for respiratory syncytial virus (RSV) hospitalization, but little is known about prophylaxis in these children.

METHODS

CARESS is a prospective registry of children who received ≥1 dose of palivizumab during the 2006-2012 RSV seasons across 32 sites in Canada. The objective was to compare respiratory illness hospitalization and RSV hospitalization (RSVH) hazard ratios in DS children aged <2 years who received palivizumab versus children who received prophylaxis for standard indications (SI) and for other medical illnesses (MI).

RESULTS

13,310 children were enrolled; DS (600; 4.5%), SI (11,081; 83.3%) and MI (1629, 12.2%), with DS children increasing over the duration from 0.1% (2006) to 4.5% (2012). Participants were significantly different in mean birth weight, gestational and enrollment age and risk factors. Children in each group received an average of 4.3 ± 1.4 (DS), 4.1 ± 1.6 (SI) and 4.5 ± 1.4 (MI) palivizumab injections per RSV season, with DS, differing significantly from SI [F(2, 13,307) = 43.6, P = 0.01] but not MI [F(2, 13 307) = 43.6, P = 0.07]. Compliance rates were similar across the groups. While a significantly greater proportion of SI children had RIHs compared with DS, [hazard ratio: 0.64 (0.48-0.84); P = 0.001] hazard ratios were similar for DS and MI. RSVH incidence rates were: 1.53%, 1.45% and 2.27% for DS, SI and MI, respectively. Neither group nor compliance affected time to RSVH.

CONCLUSIONS

The proportion of DS children who received palivizumab in CARESS has increased almost 45-fold. RSVH rates were low in DS following prophylaxis and hazards were similar to those found in SI and MI.

Kynurenine and depressive symptoms in a poststroke population

BACKGROUND AND PURPOSE

Depression is a commonly occurring and persistent sequel of stroke affecting approximately 29% of patients. An immunological hypothesis has been put forward, and synthesis of kynurenine from tryptophan has been proposed to link inflammatory activity with neurotoxicity and neurotransmitter dysfunction. This study assessed the relationship between peripheral blood kynurenine and poststroke depressive symptoms.

PATIENTS AND METHODS

This was a multisite cross-sectional observational cohort study of patients with ischemic stroke. Depressive symptoms were assessed using the Center for Epidemiological Studies Depression (CES-D) scale and divided into high, medium, and low depressive symptom tertiles. Concentrations of kynurenine and tryptophan were assayed from fasting serum samples, and the kynurenine/tryptophan ratio was compared between tertiles. Serum cytokine concentrations were assayed in a subgroup of patients, and the ratio of proinflammatory (IL-6, IL-18, IFNγ, TNF, IL-1β) to anti-inflammatory (IL-10) cytokines compared.

NLM IDENTIFIER

NCT00254020.

RESULTS

In these patients (n=86, 52.3% male, mean age 71.7±14.2 years), there were no differences in kynurenine/tryptophan ratios between CES-D scale tertiles (F 2,76=0.04, P=0.96) controlling for relevant covariates. For cytokines (n=53), serum IL-1β concentrations (F 2,52=3.55, P=0.037) and serum ratios of IL-18/IL-10 (F 2,52=3.30, P=0.046), IFNγ/IL-10 (F 2,52=4.02, P=0.025), and IL-1β/IL-10 (F 2,52=4.34, P=0.019) were elevated in the middle CES-D tertile. Post hoc analyses suggested that serum ratios of IL-18/IL-10 (ρ=0.28, P=0.04), and IL-1β/IL-10 (ρ=0.43, P=0.001), as well as IL-1β (ρ=0.29, P=0.04), were significantly associated with fatigue.

CONCLUSION

Peripheral kynurenine/tryptophan ratios were not associated with depressive symptoms in a poststroke population. However, in exploratory analyses a proinflammatory bias was identified specifically in patients with mild depressive symptoms and associated with poststroke fatigue, suggesting an avenue for future research.

Structure and photoluminescence properties of a rare-earth free red-emitting Mn2+-activated KMgBO3

Abnormal strong absorptions are observed in a Mg-based host KMgBO₃ doped by single Mn²⁺ ions, which lead to a strong red emission band centered at 636 nm.

Changes in gut microbial populations, intestinal morphology, expression of tight junction proteins, and cytokine production between two pig breeds after challenge with Escherichia coli K88: a comparative study

This study hypothesized that the gut microbial populations, intestinal morphology, and cytokine production are differentially altered in 2 different pig breeds, namely, Chinese native Jinhua pigs and European Landrace pigs, after orally challenge with enterotoxigenic Escherichia coli (ETEC) K88. A total of 12 Jinhua pigs and 12 Landrace pigs were allocated to either the nonchallenged or the challenged groups (6 pigs per group). The challenged pigs were orally administered ETEC K88, and their nonchallenged counterparts were given sterile Luria-Bertani broth. Selected gut microbial populations, intestinal morphology, mRNA expression of tight junction proteins, and the levels of ileal cytokines and secretory immunoglobulin A (sIgA) production were measured in Jinhua and Landrace pigs. The results showed that the challenged Jinhua pigs exhibited a significantly (P < 0.05) lower incidence of diarrhea compared with their Landrace counterparts. The Escherichia coli (E.coli) population and the percentage of E. coli in the total bacteria population were increased in response to ETEC K88 challenge in both Jinhua and Landrace pigs. The challenged Landrace pigs shed more E. coli (P < 0.05) and had higher percentage of E. coli in the total bacteria population in the colon (P < 0.05) compared with their Jinhua counterparts. Both pig breeds tended to exhibit greater villous atrophy and crypt depth reduction in all of the intestinal segments with challenge. The expression of tight junction proteins decreased in response to ETEC K88 challenge in both pig breeds. The levels of the proinflammatory cytokines interferon (IFN)-γ, tumor necrosis factor-α, and IL-6 and the secretion of sIgA were positively altered whereas the levels of the anti-inflammatory cytokine IL-4 and transforming growth factor (TGF)-β were negatively altered by ETEC K88 challenge in both breeds. Jinhua pigs exhibited significantly higher levels of IFN-γ and TGF-β (P < 0.05) in the challenged group. Our findings provide valuable evidence to explain the differences in the intestinal physiology between Jinhua and Landrace pigs; that is, Jinhua pigs appeared to show better growth performance, a lower incidence of diarrhea, and a lower extent of immune activation in response to ETEC K88 challenge and a higher Lactobacillus population, a higher percentage of Lactobacillus in the total bacteria population, a higher ratio of Lactobacillus to E. coli, and higher levels of tight junction proteins with and without challenge.

First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.

Urban energy mining from sewage sludge

This work showed that sewage sludge could be a strong candidate for biodiesel production. High lipid content (18-20%) with C(16-18)-carbon range was experimentally identified and measured. These lipids from sewage sludge were converted into biodiesel via the transesterification reaction with MgO-CaO/Al(2)O(3) derived from magnesium slag, and biodiesel conversion was ~98%. The experimental work enabled explaining that temperature is the main driving force for the transesterification reaction, which can be enhanced in the presence of CO(2). This also enables combination of esterification of free fatty acids and transesterification of triglycerides into a single process within 1 min in the temperature range of 350-500°C. Sewage sludge residue after extracting lipids was also a good feedstock for recovering energy via thermo-chemical processes. The impact of CO(2) co-feed on the pyrolysis/gasification process of SS residue was also investigated in this work. The CO(2) injected into the thermo-chemical process remarkably increased the generation of CO by a factor of 2. Moreover, the introduction of CO(2) into the pyrolysis/gasification process enabled reducing condensable hydrocarbons (tar) by expediting cracking; thus, utilizing CO(2) as chemical feedstock for the gasification process not only leads to higher thermal efficiency but also has environmental benefits.

Adsorption stripping voltammetry of phenol at Nafion-modified glassy carbon electrode in the presence of surfactants

In this paper, a new voltammetric method for the determination of phenol is described. In pH 8.00 phosphate buffer and in the presence of long-chain cationic surfactant-cetyltrimethylammonium bromide-phenol has a very sensitive oxidation peak at 0.47 V (vs. SCE) on the Nafion-modified glassy carbon electrode (GCE). The experimental parameters, such as supporting electrolyte and pH values, amounts of Nafion, varieties and concentration of surfactants, accumulation potential and time, as well as scan rate were optimized. The peak current is linear with the concentration of phenol in the range from 8x10(-9) to 1x10(-5) M, and the detection limit is 1x10(-9) M after being accumulated at -0.50 V (vs. SCE) for 3 min. Trace levels of phenol in water samples were determined by using this voltammetric method, the average recovery was calculated to be 99.56%.