Energy-dispersive X-ray fluorescence (EDXRF) analysis is one of the standard techniques for the evaluation of mineral deposits. The advantage of EDXRF is the fast delivery of information about the ...bulk elemental composition as well as the elemental composition of each mineral class. With micro energy-dispersive X-ray fluorescence (µ-EDXRF) analysis, information can be obtained with a micrometer resolution. However, it has some limitations. With EDXRF, light elements (e.g., lithium) cannot be detected, and the count rates for carbon, fluorine and sodium are very low. This might lead to a misinterpretation of the mineral classes and the worth of the deposit. Furthermore, the identification of the alteration phases of primary minerals is ambiguous. Here, we will present an approach to overcome the limitations of µ-EDXRF by complementing it with combined laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy. In contrast to EDXRF, LIBS is able to detect all elements, including light elements. Raman spectroscopy can identify mineral phases and eventually provide additional information on their alterations and modifications. In the present paper, we show results for two different samples covering a certain chemical and mineralogical range that demonstrate the potential of the proposed combination of methods for the chemical and mineralogical analysis of geological samples.
The endocannabinoid (eCB) 2-arachidonoylglycerol (2-AG) is a known modulator of inflammation and ligand to both, pro-inflammatory cannabinoid receptor 1 (CB1) and anti-inflammatory CB2. While the ...role of both receptors in atherogenesis has been studied extensively, the significance of 2-AG for atherogenesis is less well characterized.
The impact of 2-AG on atherogenesis was studied in two treatment groups of ApoE-/- mice. One group received the monoacylglycerol lipase (MAGL)-inhibitor JZL184 5 mg/kg i.p., which impairs 2-AG degradation and thus causes elevated 2-AG levels, the other group received vehicle for four weeks. Simultaneously, both groups were fed a high-cholesterol diet. The atherosclerotic plaque burden was assessed in frozen sections through the aortic sinus following oil red O staining and infiltrating macrophages were detected by immunofluorescence targeting CD68. In vitro, the effect of 2-AG on B6MCL macrophage migration was assessed by Boyden chamber experiments. Transcription of adhesion molecules and chemokine receptors in macrophages was assessed by qPCR.
As expected, application of the MAGL-inhibitor JZL184 resulted in a significant increase in 2-AG levels in vascular tissue (98.2 ± 16.1 nmol/g vs. 27.3 ± 4.5 nmol/g; n = 14-16; p < 0.001). ApoE-/- mice with elevated 2-AG levels displayed a significantly increased plaque burden compared to vehicle treated controls (0.44 ± 0.03 vs. 0.31 ± 0.04; n = 14; p = 0.0117). This was accompanied by a significant increase in infiltrating macrophages within the atherosclerotic vessel wall (0.33 ± 0.02 vs. 0.27 ± 0.01; n = 13-14; p = 0.0076). While there was no alteration to the white blood counts of JZL184-treated animals, 2-AG enhanced macrophage migration in vitro by 1.8 ± 0.2 -fold (n = 4-6; p = 0.0393) compared to vehicle, which was completely abolished by co-administration of either CB1- or CB2-receptor-antagonists. qPCR analyses of 2-AG-stimulated macrophages showed an enhanced transcription of the chemokine CCL5 (1.59 ± 0.23 -fold; n = 5-6; p = 0.0589) and its corresponding receptors CCR1 (2.04 ± 0.46 -fold; n = 10-11; p = 0.0472) and CCR5 (2.45 ± 0.62 -fold; n = 5-6; p = 0.0554).
Taken together, elevated 2-AG levels appear to promote atherogenesis in vivo. Our data suggest that 2-AG promotes macrophage migration, possibly by the CCL5-CCR5/CCR1 axis, and thereby contributes to vascular inflammation. Thus, decreasing vascular 2-AG levels might represent a promising therapeutic strategy in patients suffering from atherosclerosis and coronary heart disease.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Humans draw maps when communicating about places or verbally describe routes between locations. Honeybees communicate places by encoding distance and direction in their waggle dances 1. Controversy ...exists not only about the structure of spatial memory but also about the efficiency of dance communication 2–5. Some of these uncertainties were resolved by studies in which recruits' flights were monitored using harmonic radar 6, 7. We asked whether the two sources of vector information—the previously learned flight vector to a food source and the communicated vector—are represented in a common frame of spatial reference. We found that recruits redirect their outbound flights and perform novel shortcut flights between the communicated and learned locations in both directions. Guidance by beacons at the respective locations or by the panorama of the horizon was excluded. These findings indicate a spatial reference based on either large-scale vector integration or a common geocentric map-like spatial memory. Both models predict a memory structure that stores the spatial layout in such a way that decisions are made according to estimated distances and directions. The models differ with respect to the role of landmarks and the time of learning of spatial relations.
► Dance communication in honeybees is symbolic and does not require any odor signals ► Dance followers decide between the learned flight vector and the communicated vector ► Shortcutting flights are performed between communicated and learned locations ► The spatial relations of these locations are embedded in a common frame of reference
Malignancies with an extended encasement or infiltration of the aorta were previously considered inoperable. This series demonstrates replacement and subsequent resection of the thoracoabdominal ...aorta and its large branches as an adjunct to curative radical retroperitoneal and spinal tumor resection. Five consecutive patients were enrolled between 2016 and 2020, suffering from cancer of unknown primary, pleomorphic carcinoma, chordoma, rhabdoid sarcoma, and endometrial cancer metastasis. Wide surgical resection was the only curative option for these patients. For vascular replacement, extracorporeal membrane oxygenation (ECMO) was used as a partial left-heart bypass. The early technical success rate was 100% for vascular procedures and all patients underwent complete radical tumour resection with negative margins. All patients required surgical revision (liquor leak,
= 2; hematoma,
= 3; bypass revision,
= 1; bleeding,
= 1; biliary leak,
= 1). During follow-up (average 47 months, range 22-70) primary patency rates of aortic reconstructions and arterial bypasses were 100%; no patient suffered from recurrent malignant disease. Thoracoabdominal aortic replacement with rerouting of visceral and renal vessels is feasible in oncologic patients. In highly selected young patients, major vascular surgery can push the limits of oncologic surgery further, allowing a curative approach even in extensive retroperitoneal and spinal malignancies.
Cyclical parthenogenesis presents an interesting challenge for the study of sex allocation, as individuals’ allocation decisions involve both the choice between sexual and asexual reproduction, and ...the choice between sons and daughters. Male production is therefore expected to depend on ecological and evolutionary drivers of overall investment in sex, and those influencing male reproductive value during sexual periods. We manipulated experimental populations, and made repeated observations of natural populations over their growing season, to disentangle effects of population density and the timing of sex from effects of adult sex ratio on sex allocation in cyclically parthenogenetic Daphnia magna. Male production increased with population density, the major ecological driver of sexual reproduction; however, this response was dampened when the population sex ratio was more male‐biased. Thus, in line with sex ratio theory, we show that D. magna adjust offspring sex allocation in response to the current population sex ratio.
► Citation counts are a function of many variables besides scientific quality. ► Our study shows that citation counts are correlated with four further factors. ► No significant correlation was found ...between citation counts and number of authors.
A number of bibliometric studies point out that citation counts are a function of many variables besides scientific quality. In this paper our aim is to investigate these factors that usually impact the number of citation counts, using an extensive data set from the field of chemistry. The data set contains roughly 2000 manuscripts that were submitted to the journal
Angewandte Chemie International Edition (AC-IE) as short communications, reviewed by external reviewers, and either published in AC-IE or, if not accepted for publication by AC-IE, published elsewhere. As the reviewers’ ratings of the importance of the manuscripts’ results are also available to us, we can examine the extent to which certain factors that previous studies demonstrated to be generally correlated with citation counts increase the impact of papers, controlling for the quality of the manuscripts (as measured by reviewers’ ratings of the importance of the findings) in the statistical analysis. As the results show, besides being associated with quality, citation counts are correlated with the citation performance of the cited references, the language of the publishing journal, the chemical subfield, and the reputation of the authors. In this study no statistically significant correlation was found between citation counts and number of authors.
Innate lymphocyte cells (ILCs), a novel family of innate immune cells are considered to function as key orchestrators of immune defences at mucosal surfaces and to be crucial for maintaining an ...intact intestinal barrier. Accordingly, first data suggest depletion of ILCs to be involved in human immunodeficiency virus (HIV)-associated damage of the intestinal mucosa and subsequent microbial translocation. However, although ILCs are preferentially localized at mucosal surfaces, only little is known regarding distribution and function of ILCs in the human gastrointestinal tract. Here, we show that in HIV(-) individuals composition and functional capacity of intestinal ILCs is compartment-specific with group 1 ILCs representing the major fraction in the upper gastrointestinal (GI) tract, whereas ILC3 are the predominant population in ileum and colon, respectively. In addition, we present first data indicating that local cytokine concentrations, especially that of IL-7, might modulate composition of gut ILCs. Distribution of intestinal ILCs was significantly altered in HIV patients, who displayed decreased frequency of total ILCs in ileum and colon owing to reduced numbers of both CD127(+)ILC1 and ILC3. Of note, frequency of colonic ILC3 was inversely correlated with serum levels of I-FABP and sCD14, surrogate markers for loss of gut barrier integrity and microbial translocation, respectively. Both expression of the IL-7 receptor CD127 on ILCs as well as mucosal IL-7 mRNA levels were decreased in HIV(+) patients, especially in those parts of the GI tract with reduced ILC frequencies, suggesting that impaired IL-7 responses of ILCs might contribute to incomplete reconstitution of ILCs under effective anti-retroviral therapy. This is the first report comparing distribution and function of ILCs along the intestinal mucosa of the entire human gastrointestinal tract in HIV(+) and HIV(-) individuals.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This article assesses the role of the recent introduction of the minimum wage for collective bargaining coverage and works councils in Germany. The new minimum wage was initiated to strengthen German ...tariff autonomy, but effects on collective bargaining coverage are theoretically ambivalent. Using the IAB Establishment Panel, descriptive regressions show that firms covered by a collective bargaining contract are much less likely affected by the minimum wage. To construct a counterfactual for the group of affected establishments, the authors apply an entropy balancing procedure. Subsequent difference-in-differences estimates reveal a slight decline in collective bargaining participation, which falls short of statistical significance. Although the effect on opting into collective bargaining is even slightly positive, the authors observe a significant decrease in coverage through firms that exit collective agreements.
Ratings in journal peer review can be affected by sources of bias. The bias variable investigated here was the information on whether authors had suggested a possible reviewer for their manuscript, ...and whether the editor had taken up that suggestion or had chosen a reviewer that had not been suggested by the authors. Studies have shown that author-suggested reviewers rate manuscripts more favorably than editor-suggested reviewers do.
Reviewers' ratings on three evaluation criteria and the reviewers' final publication recommendations were available for 552 manuscripts (in total 1145 reviews) that were submitted to Atmospheric Chemistry and Physics, an interactive open access journal using public peer review (authors' and reviewers' comments are publicly exchanged). Public peer review is supposed to bring a new openness to the reviewing process that will enhance its objectivity. In the statistical analysis the quality of a manuscript was controlled for to prevent favorable reviewers' ratings from being attributable to quality instead of to the bias variable.
Our results agree with those from other studies that editor-suggested reviewers rated manuscripts between 30% and 42% less favorably than author-suggested reviewers. Against this backdrop journal editors should consider either doing without the use of author-suggested reviewers or, if they are used, bringing in more than one editor-suggested reviewer for the review process (so that the review by author-suggested reviewers can be put in perspective).
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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► The mean correlation between the
h index and variants of the
h index (such as the
g index) varies between .8 and .9. ► There is redundancy between most of the
h index variants and ...the
h index. ► The
h index variants MII and
m index make a non-redundant contribution to the
h index.
This paper presents the first meta-analysis of studies that computed correlations between the
h index and variants of the
h index (such as the
g index; in total 37 different variants) that have been proposed and discussed in the literature. A high correlation between the
h index and its variants would indicate that the
h index variants hardly provide added information to the
h index. This meta-analysis included 135 correlation coefficients from 32 studies. The studies were based on a total sample size of
N
=
9005; on average, each study had a sample size of
n
=
257. The results of a three-level cross-classified mixed-effects meta-analysis show a high correlation between the
h index and its variants: Depending on the model, the mean correlation coefficient varies between .8 and .9. This means that there is redundancy between most of the
h index variants and the
h index. There is a statistically significant study-to-study variation of the correlation coefficients in the information they yield. The lowest correlation coefficients with the
h index are found for the
h index variants MII and
m index. Hence, these
h index variants make a non-redundant contribution to the
h index.
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