1,551 research outputs found
The Study of Dust Formation of Six Tidal Disruption Events
This paper investigates eleven (UV-)optical-infrared (IR) spectral energy
distributions (SEDs) of six tidal disruption events (TDEs), which are
ASASSN-14li, ASASSN-15lh, ASASSN-18ul, ASASSN-18zj, PS18kh, and ZTF18acaqdaa.
We find that all the SEDs show evident IR excesses. We invoke the blackbody
plus dust emission model to fit the SEDs, and find that the model can account
for the SEDs. The derived masses of the dust surrounding ASASSN-14li,
ASASSN-15lh, ASASSN-18ul, ASASSN-18zj, PS18kh, and ZTF18acaqdaa are
respectively ,
,
,
,
, and , if the dust is graphite (silicate). The
temperature of the graphite (silicate) dust of the six TDEs are respectively
\,K, \,K,
\,K, \,K, \,K, and
\,K. By comparing the derived temperatures to the
vaporization temperature of graphite (\,K) and silicate (\,K), we suggest that the IR excesses of PS18kh can be explained by
both the graphite and silicate dust, the rest five TDEs favor the graphite dust
while the silicate dust model cannot be excluded. Moreover, we demonstrate the
lower limits of the radii of the dust shells surrounding the six TDEs are
significantly larger than those of the radii of the photospheres at the first
epochs of SEDs, indicating that the dust might exist before the the TDEs
occurred.Comment: 13 pages, 4 figures, 4 tables, submitted to Ap
Pentaaqua(1H-benzimidazole-5,6-dicarboxylato-κN 3)cobalt(II) pentahydrate
In the title mononuclear complex, [Co(C9H4N2O4)(H2O)5]·5H2O, the CoII atom exhibits a distorted octahedral geometry involving an N atom of a 1H-benzimidazole-5,6-dicarboxylate ligand and five water O atoms. A supramolecular network is generated through intermolecular O—H⋯O hydrogen-bonding interactions involving the coordinated and uncoordinated water molecules and the carboxyl O atoms of the organic ligand. An intermolecular N—H⋯O hydrogen bond is also observed
Bifid mandibular canals and their cortex thicknesses: A comparison study on images obtained from cone-beam and multislice computed tomography
AbstractBackground/purposeHigh prevalence of bifid mandibular canals has been visualized with various types of computerized tomography (CT). Along the canals, a various ranged corticalization was recently reported. The depiction of the fine anatomic structures on multislice and cone-beam CT images was compared.Material and methodsThe presence or absence of the bifid canal was assessed on 327 images obtained by multislice CT (MSCT; n = 173) or by cone-beam CT (CBCT; n = 154), according to the configuration. The cortex thickness and distribution were also assessed.ResultsThe prevalence of bifid canal detected by CBCT was significantly greater than that detected by MSCT (42.2% vs. 18.7% for hemi-mandibles and 58.4% vs. 30.6% for patients). Cortical thickness recorded by CBCT was significantly thinner than that recorded by MSCT (0.48 mm vs. 0.65 mm, P < 0.001); however, the distributions of corticalization detected by the two tomography methods were similar. There was a significant association of cortex thickness with CT type and corticalization degree (R2 = 0.530, P < 0.001).ConclusionThinner cortices, but greater prevalence of bifid canals recorded by CBCT, compared to MSCT, suggests that clinicians should be cautious when using CT to interpret this fine anatomic structure
catena-Poly[[diaqua(1,10-phenanthroline-κ2 N,N′)nickel(II)]-μ-1H-benzimidazole-5,6-dicarboxylato-κ2 N 3:O 6]
In the title complex, [Ni(C9H4N2O4)(C12H8N2)(H2O)2]n, the NiII atom is hexacoordinated by one N and one O atom from two different 1H-benzimidazole-5,6-dicarboxylate ligands, two N atoms from one 1,10-phenanthroline ligand and two water molecules. The flexible 1H-benzimidazole-5,6-dicarboxylate ligands link the NiII centres, forming an infinite zigzag chain parallel to [001]. The crystal packing is governed by intermolecular hydrogen-bonding interactions of the O—H⋯O, N—H⋯O and C—H⋯O types
Clinical Characteristics of Hydrocephalus Following the Treatment of Pyogenic Ventriculitis Caused by Multi/Extensive Drug-Resistant Gram-Negative Bacilli, Acinetobacter Baumannii, and Klebsiella Pneumoniae
ObjectiveHydrocephalus is common after ventriculitis. This study explores hydrocephalus's clinical characteristics following pyogenic ventriculitis due to multidrug-resistant and extensively drug-resistant Acinetobacter baumannii and Klebsiella pneumoniae.Patients and MethodsWe retrospectively reviewed patients with post-neurosurgical pyogenic ventriculitis due to multidrug-resistant and extensively drug-resistant A. baumannii and K. pneumoniae in our department between January 2014 and June 2020. Once diagnosed, patients received intraventricular lavage followed by daily intraventricular administration of Colistin (polymyxin-E). The patient's clinical/radiographic findings were analyzed and evaluated 6 months after discharge.ResultsIn total, 48 cases were included in this study, and 25% were female. The median age was 45 (SD ± 15) years old. Median intraventricular Colistin administration to acquire sterile cerebrospinal fluid (CSF) was 20 days. Forty-one patients developed hydrocephalus; among them, 18 (43%) had multiloculated hydrocephalus (MLH), 23 (56%) had uni/non-loculated hydrocephalus (ULH/NLH), and 7 (17%) did not develop hydrocephalus. The patients with MLH had (15 days) delayed initiation of intraventricular irrigation (p < 0.022). They had (32 days) longer intraventricular Colistin (p < 0.003) and showed worse outcomes in terms of Glasgow outcome score (GOS) at 6 months follow-up than those without hydrocephalus. The mean score of the MLH group was 1.67 (SD1.23), and ULH/NLH was 2.61 (SD1.4) at p < 0.008.ConclusionMultiloculated hydrocephalus is common in patients receiving delayed intraventricular administration of Colistin and required a longer duration on intraventricular Colistin to treat the pyogenic ventriculitis caused by multidrug/extensive drug-resistant A. baumannii and K. pneumoniae. It is associated with worse clinical outcomes
A network meta-analysis on the improvement of cognition in patients with vascular dementia by different acupuncture therapies
IntroductionThe second most prevalent cause of dementia is vascular dementia (VaD). Furthermore, acupuncture is a relatively safe and effective traditional therapy for individuals with VaD. We performed a network meta-analysis to assess the effectiveness and safety of various acupuncture therapies for VaD based on existing research.MethodsWe searched six electronic databases to screen for randomized controlled trials (RCTs) comparing different acupuncture treatments in VaD patients. The Cochrne tool (Review Manager 5.3) was used to evaluate the risk of bias of the included RCTs. Based on the Grading of Recommendations Assessment, Development and Evaluation framework, we assessed the confidence in the evidence using the Confidence In the results from Network Meta-Analysis approach. We used the frequency approach to perform the network meta-analysis. Data were analyzed using R 4.1.1.ResultsIn total, we included 46 eligible studies. The results of the network analysis showed that the combined interventions of moxibustion (MB) with body acupuncture (BA) (MB + BA) and electroacupuncture (EA) with scalp acupuncture (SA) with BA (EA + SA + BA) were more effective in improving cognitive functions and activities of daily living compared with SA or BA alone. However, in the subgroup analysis, EA + SA + BA showed better efficacy in short- and mid-term acupuncture compared with other acupuncture therapies.ConclusionCombined acupuncture therapy may be a safe and effective intervention for individuals with VaD, and MB + BA and EA + SA + BA appear to be the most effective interventions. However, because the analysis of this study was based on low-to-moderate evidence, there remains no strong supporting evidence. Thus, high-quality, large-scale, and long-term studies should be conducted in the future to assess the effectiveness and safety of acupuncture in VaD.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier: CRD42022354573
Mitochondrial Dysfunction in Neural Injury
Mitochondria are the double membrane organelles providing most of the energy for cells. In addition, mitochondria also play essential roles in various cellular biological processes such as calcium signaling, apoptosis, ROS generation, cell growth, and cell cycle. Mitochondrial dysfunction is observed in various neurological disorders which harbor acute and chronic neural injury such as neurodegenerative diseases and ischemia, hypoxia-induced brain injury. In this review, we describe how mitochondrial dysfunction contributes to the pathogenesis of neurological disorders which manifest chronic or acute neural injury
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