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Heating experiments of the Tagish Lake meteorite: Investigation of the effects of short-term heating on chondritic organics
We present in this study the effects of short-term heating on organics in the Tagish Lake meteorite and how the difference in the heating conditions can modify the organic matter (OM) in a way that complicates the interpretation of a parent body’s heating extent with common cosmothermometers. The kinetics of short-term heating and its influence on the organic structure are not well understood, and any study of OM is further complicated by the complex alteration processes of the thermally metamorphosed carbonaceous chondrites—potential analogues of the target asteroid Ryugu of the Hayabusa2 mission—which had experienced posthydration, short-duration local heating. In an attempt to understand the effects of short-term heating on chondritic OM, we investigated the change in the OM contents of the experimentally heated Tagish Lake meteorite samples using Raman spectroscopy, scanning transmission X-ray microscopy utilizing X-ray absorption near edge structure spectroscopy, and ultraperformance liquid chromatography fluorescence detection and quadrupole time of flight hybrid mass spectrometry. Our experiment suggests that graphitization of OM did not take place despite the samples being heated to 900 °C for 96 h, as the OM maturity trend was influenced by the heating conditions, kinetics, and the nature of the OM precursor, such as the presence of abundant oxygenated moieties. Although both the intensity of the 1s σ* exciton cannot be used to accurately interpret the peak metamorphic temperature of the experimentally heated Tagish Lake sample, the Raman graphite band widths of the heated products significantly differ from that of chondritic OM modified by long-term internal heating
DYNAMICS OF MARXISM BEFORE AND AFTER THE DIGITAL ERA
This paper explains the role of the mass media. In this digital era, almost all people know or use this media to receive or seek various information, which is undoubtedly unlimited. In this digital era, everything is advanced from technology increasingly being developed over time—speed in its delivery from the source to the broader community. Without limitation, the information can be spread among countries—the large variety of media platforms available. Now, of course, the media are also a political tool. Not left behind in the discussion of this paper regarding the policies of Marxism
The prevalence, clinical characteristics, and brain MRI changes in intracranial artery hypoplasia: a retrospective single-center cross-sectional study
reduced cerebral blood flow, increased atherosclerosis, and aneurysm formation. This study aimed to describe the profile of vertebral artery hypoplasia (VAH), anterior CAH (ACAH), and posterior CAH (PCAH) in symptomatic subjects.
Methods: This was a retrospective cross-sectional study using medical record in a secondary private hospital in Jakarta, Indonesia, in January-December 2022. The inclusion criteria were age ≥18 years with neurological symptoms, underwent brain MRI, and being diagnosed with CAH using DSA. The exclusion criteria were findings of other vascular pathologies including dissection and >50% intracranial vessel stenosis. Demographics of age, sex, body mass index (BMI), hypertension, diabetes, cardiac disorder, and previous stroke were analyzed among VAH, PCAH, and ACAH groups.
Results: Of 769 subjects with clinical symptoms undergoing DSA, there were 66 (8.6%) cases of intracranial artery hypoplasia, including VAH (4.6%), PCAH (1.2%), and ACAH (2.9%). Subjects were predominantly old (53.2±10.1 years), male (53.0%), with BMI of 24.9±3.9 kg/m2 and hypertension (69.7%). Previous stroke (69.7%) was more prevalent than in previous study (28.1%). Stroke and brain ischemic lesion were detected in 89.4% and 84.8% cases. No differences were found in all parameters among all groups, but posterior circulation symptoms tended to be found in VAH (28.1%) than general stroke (20.3%).
Conclusions: The high percentage of recurrent stroke and corresponding clinical symptoms associated with CAH supported that CAH may be a risk factor for clinical symptoms, including stroke, regardless of the involved artery
Whom do we trust - Booters and SSL/TLS certificates
SPRING 2016, 11th edition of the SPRING series, is a single-track event that was sponsored by the special interest group Security – Intrusion Detection and Response (SIDAR) of the German Informatics Society (GI). The purpose of SPRING is to provide young researchers the opportunity to discuss their work with other students and specialists in the research area of IT security. In particular, SPRING is a venue for presentation of early-stage research and solicits submission of scientific papers presenting novel research on malware analysis, intrusion detection, and related systems security topics. As per our tradition, SPRING encourages submissions from the following broad areas: Analysis of vulnerabilities, intrusion detection, malware, incident management and forensics. This year the SPRING 2016 graduate workshop was held in Darmstadt, Germany, and was hosted at the University of Applied Sciences. SPRING took place from the 2nd to the 3rd of June 2016 and was the eleventh edition of the graduate workshop on IT security. It followed the successful events in Neubiberg in 2015, Bochum in 2014, Munich in 2013, Berlin in 2012, Bochum in 2011, Bonn in 2010, Stuttgart in 2009, Mannheim in 2008, Dortmund in 2007 and Berlin in 2006. SPRING 2016 was organized in a 2-day program to encourage interactions between all participants. The program consists of a main track and opening research keynotes. The presented volume includes all extended abstracts presented at SPRING 2016 as defined within the overall final program
A FALSE POSITIVE FOR OCEAN GLINT ON EXOPLANETS: THE LATITUDE-ALBEDO EFFECT
ABSTRACT Identifying liquid water on the surface of planets is a high priority, as this traditionally defines habitability. One proposed signature of oceans is specular reflection ("glint"), which increases the apparent albedo of a planet at crescent phases. We post-process a global climate model of an Earth-like planet to simulate reflected light curves. Significantly, we obtain glint-like phase variations even though we do not include specular reflection in our model. This false positive is the product of two generic properties: (1) for modest obliquities, a planet's poles receive less orbit-averaged stellar flux than its equator, so the poles are more likely to be covered in highly reflective snow and ice; and (2) we show that reflected light from a modest-obliquity planet at crescent phases probes higher latitudes than at gibbous phases, therefore a planet's apparent albedo will naturally increase at crescent phase. We suggest that this "latitude-albedo effect" will operate even for large obliquities: in that case the equator receives less orbit-averaged flux than the poles, and the equator is preferentially sampled at crescent phase. Using rotational and orbital color variations to map the surfaces of directly imaged planets and estimate their obliquity will therefore be a necessary pre-condition for properly interpreting their reflected phase variations. The latitude-albedo effect is a particularly convincing glint false positive for zero-obliquity planets, and such worlds are not amenable to latitudinal mapping. This effect severely limits the utility of specular reflection for detecting oceans on exoplanets
A case of esophageal cancer with mesojejunal lymph node metastasis after total gastrectomy
A 56-year-old man was diagnosed with esophageal cancer by upper gastrointestinal endoscopy for examination of dysphagia. The patient had undergone total gastrectomy and jejunal interposition 4 years previously for a gastric cancer at the pT1N0M0 stage according to the UICC-TNM classification. Enhanced CT findings revealed a 3-cm-diameter mass located near the superior mesenteric artery. We conducted subtotal esophagectomy associated with partial jejunectomy including mesojejunectomy. The mass was histologically diagnosed to be mesojejunal lymph node metastasis from esophageal cancer. Mesojejunal lymph node metastasis from esophageal cancer developing after total gastrectomy has been reported in only three cases including ours. The present lymph node metastases may have occurred via the newly developed lymphatic drainage route through the esophagojejunostomy, and this metastatic lymph node can be considered the regional lymph node. Therefore, resection of the interposed jejunal limb with mesojejunectomy may be rational in surgery on esophageal cancer developing after total gastrectomy
Thermal Phases of Earth-Like Planets: Estimating Thermal Inertia from Eccentricity, Obliquity, and Diurnal Forcing
In order to understand the climate on terrestrial planets orbiting nearby
Sun-like stars, one would like to know their thermal inertia. We use a global
climate model to simulate the thermal phase variations of Earth-analogs and
test whether these data could distinguish between planets with different heat
storage and heat transport characteristics. In particular, we consider a
temperate climate with polar ice caps (like modern Earth), and a snowball state
where the oceans are globally covered in ice. We first quantitatively study the
periodic radiative forcing from, and climatic response to, rotation, obliquity,
and eccentricity. Orbital eccentricity and seasonal changes in albedo cause
variations in the global-mean absorbed flux. The responses of the two climates
to these global seasons indicate that the temperate planet has 3 times the bulk
heat capacity of the snowball planet due to the presence of liquid water
oceans. The temperate obliquity seasons are weaker than one would expect based
on thermal inertia alone; this is due to cross-equatorial oceanic and
atmospheric energy transport. Thermal inertia and cross-equatorial heat
transport have qualitatively different effects on obliquity seasons, insofar as
heat transport tends to reduce seasonal amplitude without inducing a phase lag.
For an Earth-like planet, however, this effect is masked by the mixing of
signals from low thermal inertia regions (sea ice and land) with that from high
thermal inertia regions (oceans), which also produces a damped response with
small phase lag. We then simulate thermal lightcurves as they would appear to a
high-contrast imaging mission (TPF-I/Darwin) and consider the inverse problem
of estimating thermal inertia based solely on time-resolved photometry.
[Abridged]Comment: 14 pages, 12 figures, ApJ accepte
Efficacy of a hybrid assistive limb in post-stroke hemiplegic patients: a preliminary report
<p>Abstract</p> <p>Background</p> <p>Robotic devices are expected to be widely used in various applications including support for the independent mobility of the elderly with muscle weakness and people with impaired motor function as well as support for nursing care that involves heavy laborious work. We evaluated the effects of a hybrid assistive limb robot suit on the gait of stroke patients undergoing rehabilitation.</p> <p>Methods</p> <p>The study group comprised 16 stroke patients with severe hemiplegia. All patients underwent gait training. Four patients required assistance, and 12 needed supervision while walking. The stride length, walking speed and physiological cost index on wearing the hybrid assistive limb suit and a knee-ankle-foot orthosis were compared.</p> <p>Results</p> <p>The hybrid assistive limb suit increased the stride length and walking speed in 4 of 16 patients. The patients whose walking speed decreased on wearing the hybrid assistive limb suit either had not received sufficient gait training or had an established gait pattern with a knee-ankle-foot orthosis using a quad cane. The physiological cost index increased after wearing the hybrid assistive limb suit in 12 patients, but removal of the suit led to a decrease in the physiological cost index values to equivalent levels prior to the use of the suit.</p> <p>Conclusions</p> <p>Although the hybrid assistive limb suit is not useful for all hemiplegic patients, it may increase the walking speed and affect the walking ability. Further investigation would clarify its indication for the possibility of gait training.</p
Hypercapnia increases ACE2 expression and pseudo-SARS-CoV-2 entry in bronchial epithelial cells by augmenting cellular cholesterol
Patients with chronic lung disease, obesity, and other co-morbid conditions are at increased risk of severe illness and death when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hypercapnia, the elevation of CO2 in blood and tissue, commonly occurs in patients with severe acute and chronic lung disease, including those with pulmonary infections, and is also associated with high mortality risk. We previously reported that hypercapnia increases viral replication and mortality of influenza A virus infection in mice. We have also shown that culture in elevated CO2 upregulates expression of cholesterol synthesis genes in primary human bronchial epithelial cells. Interestingly, factors that increase the cholesterol content of lipid rafts and lipid droplets, platforms for viral entry and assembly, enhance SARS-CoV-2 infection. In the current study, we investigated the effects of hypercapnia on ACE2 expression and entry of SARS-CoV-2 pseudovirus (p-SARS-CoV-2) into airway epithelial cells. We found that hypercapnia increased ACE2 expression and p-SARS-CoV-2 uptake by airway epithelium in mice, and in cultured VERO and human bronchial epithelial cells. Hypercapnia also increased total cellular and lipid raft-associated cholesterol in epithelial cells. Moreover, reducing cholesterol synthesis with inhibitors of sterol regulatory element binding protein 2 (SREBP2) or statins, and depletion of cellular cholesterol, each blocked the hypercapnia-induced increases in ACE2 expression and p-SARS-CoV-2 entry into epithelial cells. Cigarette smoke extract (CSE) also increased ACE2 expression, p-SARS-CoV-2 entry and cholesterol accumulation in epithelial cells, an effect not additive to that of hypercapnia, but also inhibited by statins. These findings reveal a mechanism that may account, in part, for poor clinical outcomes of SARS-CoV-2 infection in patients with advanced lung disease and hypercapnia, and in those who smoke cigarettes. Further, our results suggest the possibility that cholesterol-lowering therapies may be of particular benefit in patients with hypercapnia when exposed to or infected with SARS-CoV-2
Reflex conditioning: a new strategy for improving motor function after spinal cord injury: Chen et al.
Spinal reflex conditioning changes reflex size, induces spinal cord plasticity, and modifies locomotion. Appropriate reflex conditioning can improve walking in rats after spinal cord injury (SCI). Reflex conditioning offers a new therapeutic strategy for restoring function in people with SCI. This approach can address the specific deficits of individuals with SCI by targeting specific reflex pathways for increased or decreased responsiveness. In addition, once clinically significant regeneration can be achieved, reflex conditioning could provide a means of re-educating the newly (and probably imperfectly) reconnected spinal cord
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