julilili42/papers huggingface dataset:
Resolution enhancement for low-temperature scanning microscopy by cryo-immersion
2016-06-06

Here we report a simple way to enhance the resolution of a confocal scanning microscope under cryogenic conditions. Using a microscope objective (MO) with high numerical aperture (NA = 1.25) and 1-propanol as an immersion fluid with low freezing temperature we were able to reach an imaging resolution at 160 K comparable to ambient conditions. The MO and the sample were both placed inside the inner chamber of the cryostat to reduce distortions induced by temperature gradients. The image quality of our commercially available MO was further enhanced by scanning the sample (sample scanning) in contrast to beam scanning. The ease of the whole procedure marks an essential step towards the development of cryo high-resolution microscopy and correlative light and electron cryo microscopy (cryoCLEM).
Labor income risk and households’ risky asset holdings
2016-06-06

Purpose Financial theory suggests that with increasing labor income risk, the reluctance of households to hold stocks increases. Therefore, this paper aims to investigate the determinants of a household’s decision on whether to invest in risky financial assets. Design/methodology/approach Income risk is measured as the observed variation of household income over a five-year period. The authors use both the time and the cross-sectional dimension of the German socio-economic panel to control for unobserved heterogeneity. Findings The authors find that indeed higher variation, i.e. higher income risk, reduces the propensity to invest in risky assets. However, when controlling for household heterogeneity, as well as subjective measures of a household’s financial situation (income satisfaction, worries about financial situation), the impact of observed labor income variation vanishes. It is therefore concluded that in particular the perception of investment risk and of the riskiness of the environment determines the investment decision to a great extent. Originality/value The paper contributes to a better understanding of a household’s investment decision-making process. To the best of the authors’ knowledge, it is the first to fully exploit the panel structure of the data to control for unobserved heterogeneity which leads to novel conclusions with respect to the effect of labor income.
Molecular Origin of the Charge Carrier Mobility in Small Molecule Organic Semiconductors
2016-06-07

Small‐molecule organic semiconductors are used in a wide spectrum of applications, ranging from organic light emitting diodes to organic photovoltaics. However, the low carrier mobility severely limits their potential, e.g., for large area devices. A number of factors determine mobility, such as molecular packing, electronic structure, dipole moment, and polarizability. Presently, quantitative ab initio models to assess the influence of these molecule‐dependent properties are lacking. Here, a multiscale model is presented, which provides an accurate prediction of experimental data over ten orders of magnitude in mobility, and allows for the decomposition of the carrier mobility into molecule‐specific quantities. Molecule‐specific quantitative measures are provided how two single molecule properties, the dependence of the orbital energy on conformation, and the dipole‐induced polarization determine mobility for hole‐transport materials. The availability of first‐principles based models to compute key performance characteristics of organic semiconductors may enable in silico screening of numerous chemical compounds for the development of highly efficient optoelectronic devices.
The Prion-Like Properties of Amyloid-β Assemblies: Implications for Alzheimer's Disease
2016-06-07

Since the discovery that prion diseases can be transmitted to experimental animals by inoculation with afflicted brain matter, researchers have speculated that the brains of patients suffering from other neurodegenerative diseases might also harbor causative agents with transmissible properties. Foremost among these disorders is Alzheimer's disease (AD), the most common cause of dementia in the elderly. A growing body of research supports the concept that the pathogenesis of AD is initiated and sustained by the endogenous, seeded misfolding and aggregation of the protein fragment amyloid-β (Aβ). At the molecular level, this mechanism of nucleated protein self-assembly is virtually identical to that of prions consisting of the prion protein (PrP). The formation, propagation, and spread of Aβ seeds within the brain can thus be considered a fundamental feature of AD pathogenesis.
Informal processing of electronic waste at Agbogbloshie, Ghana: workers’ knowledge about associated health hazards and alternative livelihoods
2016-06-07

Aims: This study was conducted to investigate the electronic waste workers’ knowledge about the potential health hazards associated with their work as well as the livelihood alternatives that they would prefer if they were given the opportunity. Methods: A qualitative cross-sectional study was conducted to gather empirical information on e-waste workers’ knowledge about the potential hazards associated with their work and the livelihood alternatives to e-waste recycling with a sample consisting of twenty all-male electronic waste workers at the Agbogbloshie scrap metal yard in Accra, Ghana. Results: Electronic waste workers at Agbogbloshie were found to be exposed to a variety of injuries and illnesses. The workers’ knowledge of the association between their health status and their work was generally poor. Apart from the physical injuries, they did not believe their work played any negative role in their health conditions. They preferred occupations such as farming or professional driving located in the northern region of Ghana to be closer to their families. Conclusions: The study concludes that the low knowledge level of the workers on the hazards that are associated with their work has implications for them accepting technologies to protect them and the natural environment from contamination. It is therefore imperative for any intervention to consider the current low level of knowledge and actively educate the workers to raise their awareness level, taking into account the provision of opportunities for workers to acquire applicable skills for future employment in other fields.
Associations Between Helminth Infections, Plasmodium falciparum Parasite Carriage and Antibody Responses to Sexual and Asexual Stage Malarial Antigens
2016-06-07

Infections with helminths and Plasmodium spp. overlap in their geographical distribution. It has been postulated that helminth infections may influence malarial transmission by altering Plasmodium falciparum gametocytogenesis. This cross-sectional study assessed the effect of helminth infections on P. falciparum gametocyte carriage and on humoral immune responses to sexual stage antigens in Gabon. Schistosoma haematobium and filarial infections as well as P. falciparum asexual forms and gametocyte carriage were determined. The antibody responses measured were to sexual (Pfs230, Pfs48/45) and asexual P. falciparum antigens (AMA1, MSP1, and GLURP). A total of 287 subjects were included. The prevalence of microscopically detectable P. falciparum asexual parasites was higher in S. haematobium –infected subjects in comparison to their uninfected counterparts (47% versus 26%, P = 0.003), but this was not different when filarial infections were considered. Plasmodium falciparum gametocyte carriage was similar between Schistosoma - or filaria-infected and uninfected subjects. We observed a significant decrease of Pfs48/45 immunoglobulin G titer in S. haematobium –infected subjects ( P = 0.037), whereas no difference was seen for Pfs230 antibody titer, nor for antibodies to AMA1, MSP1, or GLURP. Our findings suggest an effect of S. haematobium on antibody responses to some P. falciparum gametocyte antigens that may have consequences for transmission-blocking immunity.
Intramolecular Tetrylene Lewis Adducts: Synthesis and Reactivity
2016-06-07

Abstract A series of benzyl(diphenylphosphino) and o ‐phenyl(diphenlyphosphino) substituted germylenes and plumbylenes were synthesized by nucleophilic substitution between the respective lithium reagent and tetrylene halide. The Lewis pairs were characterized by X‐ray crystallography and NMR spectroscopy. The reactivity of the tetrylenes was investigated with respect to azide addition. In the germylene case, the germaniumimide was formed as the kinetically controlled product, which rearranges upon heating to give the phosphinimide. The stannylene and plumbylene derivatives react with adamantylazide to give the azide adducts. 1‐Pentene reacts diastereoselectively with the phosphagermirane to give a cyclic addition product. Trimethysilylacetylene shows an addition with the benzylphosphino‐substituted germylene and plumbylene to give the cycloheteropentene molecules. The addition product between phenylacetylene and the four membered Ge‐P adduct shows after addition at room temperature a 1,4‐phenylmigration to give a cyclic phosphine. Alkylnitrene insertion into a Ge−C bond of the alkyne addition product of the phosphagermirane was found in reaction with adamantylazide.
Structural Ultrasound of the Medial Temporal Lobe in Alzheimer’s Disease
2016-06-07

Abstract Purpose One of the anatomical hallmarks of Alzheimer’s disease (AD) is the atrophy of the medial temporal lobe (MTL), yet cost-effective and broadly available methodological alternatives to the current imaging tools for screening of this brain area are not currently available. Materials and Methods Using structural transcranial ultrasound (TCS), we attempted to visualize and measure the MTL, and compared the results of 32 AD patients and 84 healthy controls (HC). The MTL and the surrounding space were defined in the coronal plane on TCS. A ratio of the height of the MTL/height of the choroidal fissure (M/F) was calculated in order to obtain a regional proportion. Results An insufficient temporal bone window was identified in 22 % of the AD patients and 12 % of the HCs. The results showed that the ratio of M/F was significantly smaller in the AD group on both sides (p = 0.004 right, p = 0.007 left side). Furthermore, the M/F ratio made it possible to discriminate AD patients from HCs with a sensitivity of 83 % (right)/73 % (left) and a specificity of 76 % (right)/72 % (left) which is basically comparable to results published for magnetic resonance imaging. The measurements showed substantial intra/interrater reliability (ICC:0.79/0.69). Conclusion These results suggest that utilization of structural TCS may possibly constitute a cheap and easy-to-use supplement to other techniques for the diagnosis of AD. It may be especially useful as a screening tool in the large population of individuals with cognitive decline. Further studies are needed to validate this novel method.
Towards tracer dose reduction in PET studies: Simulation of dose reduction by retrospective randomized undersampling of list-mode data.
2016-06-07

Simulation of PET tracer dose reduction is possible with retrospective undersampling of list-mode data. Resulting simulated low-dose images have equivalent characteristics with PET images actually measured at lower doses and can be used to derive optimal tracer dose regimes.
GK Persei and EX Hydrae: Intermediate polars with small magnetospheres
2016-06-07

\\n Observed hard X-ray spectra of intermediate polars are determined mainly by the accretion flow velocity at the white dwarf surface, which is normally close to the free-fall velocity. This allows us to estimate the white dwarf masses as the white dwarf mass-radius relation M − R and the expected free-fall velocities at the surface are well known. This method is widely used. However, derived white dwarf masses M can be systematically underestimated because the accretion flow is stopped at, and re-accelerates from, the magnetospheric boundary Rm and, therefore, its velocity at the surface is lower than free fall. To avoid this problem, we computed a two-parameter set of model hard X-ray spectra, which allows us to constrain a degenerate M − Rm dependence. Previous works showed that power spectra of accreting X-ray pulsars and intermediate polars exhibit breaks at frequencies corresponding to Keplerian frequencies at the magnetospheric boundary. Therefore, the break frequency νb in an intermediate polar power spectrum gives another relation in the M − Rm plane. The intersection of the two dependences allows us, therefore, to determine the white dwarf mass and magnetospheric radius simultaneously. To verify the method, we analysed the archival Suzaku observation of EX Hya, obtaining M/M⊙ = 0.73 ± 0.06 and Rm/R = 2.6 ± 0.4, which is consistent with the values determined by other authors. Subsequently, we applied the same method to a recent NuSTAR observation of another intermediate polar GK Per performed during an outburst and found M/M⊙ = 0.86 ± 0.02 and Rm/R = 2.8 ± 0.2. The long duration observations of GK Per in quiescence performed by Swift/BAT and INTEGRAL observatories indicate increase of magnetosphere radius Rm at lower accretion rates.\\n
Evaluation of the rule-of-thumb: calculation of the toe allowance for developing feet
2016-06-07

The amount of toe allowance (TA, the space in front of the toes) in children's shoes is physiologically important and often estimated by the rule-of-the-parent's-thumb. Besides this, other rules-of-thumb exist mainly based on experiences or footprint analysis. The aim of this study is to scientifically evaluate these rules-of-thumb. TA was calculated as a function of growth rate, foot extension, and walking advance based on three-dimensional (3D) foot scans of 2554 children (6–16 years) during standing and walking. Foot extension was determined as the difference in foot length between static and dynamic weight-bearing, walking advance as movement of the most anterior point of toes, and growth rate as semi-annual foot growth. TA was smaller than all rules-of-thumb and was influenced by gender and foot length. These findings primarily present TA based on 3D foot scans which is important for shoe construction. It is recommended to use 90th percentiles instead of mean values for the construction of TA.
Cav1.4 L-Type Calcium Channels Contribute to Calpain Activation in Degenerating Photoreceptors of rd1 Mice
2016-06-07

Retinitis pigmentosa is an inherited blinding disorder characterized by progressive degeneration and loss of photoreceptors. The exact mechanism of degeneration and cell death of photoreceptors is not known, but is thought to involve disturbed Ca2+-signaling. Ca2+ can enter the photoreceptor cell via outer segment cyclic nucleotide-gated (CNG) channels or synaptic Cav1.4 L-type voltage-gated calcium channels (VGCC). Previously, we have shown that genetic ablation of the Cngb1 gene encoding the B subunit of the rod CNG channel delays the fast progressing degeneration in the rd1 mutant mouse model of retinitis pigmentosa. In this study, we crossbred rd1 mice with the Cacna1f-deficient mouse lacking the Cav1.4 α1 subunit of the L-type VGCC. Longitudinal in vivo examinations of photoreceptor layer thickness by optical coherence tomography revealed a significant, but not sustained delay of retinal degeneration in Cacna1f x rd1 double mutant mice compared to rd1 mice. This was accompanied by a reduction of TUNEL positive cells in the early phase of rod degeneration. Remarkably, Cacna1f x rd1 double mutant mice displayed a strong decrease in the activation of the Ca2+-dependent protease calpain during photoreceptor loss. Our results show that genetic deletion of the synaptic Cav1.4 L-type VGCCs impairs calpain activation and leads to a short-term preservation of photoreceptors in the rd1 mouse.
The Penefit of Salience: Salient Accented, but Not Unaccented Words Reveal Accent Adaptation Effects
2016-06-07

In two eye-tracking experiments, the effects of salience in accent training and speech accentedness on spoken-word recognition were investigated. Salience was expected to increase a stimulus' prominence and therefore promote learning. A training-test paradigm was used on native German participants utilizing an artificial German accent. Salience was elicited by two different criteria: production and listening training as a subjective criterion and accented (Experiment 1) and canonical test words (Experiment 2) as an objective criterion. During training in Experiment 1, participants either read single German words out loud and deliberately devoiced initial voiced stop consonants (e.g., Balken-"beam" pronounced as (*) Palken), or they listened to pre-recorded words with the same accent. In a subsequent eye-tracking experiment, looks to auditorily presented target words with the accent were analyzed. Participants from both training conditions fixated accented target words more often than a control group without training. Training was identical in Experiment 2, but during test, canonical German words that overlapped in onset with the accented words from training were presented as target words (e.g., Palme-"palm tree" overlapped in onset with the training word (*) Palken) rather than accented words. This time, no training effect was observed; recognition of canonical word forms was not affected by having learned the accent. Therefore, accent learning was only visible when the accented test tokens in Experiment 1, which were not included in the test of Experiment 2, possessed sufficient salience based on the objective criterion "accent." These effects were not modified by the subjective criterion of salience from the training modality.
An Encounter of al-ʿAbbās b. Ḥamza (d. 288/901) with Dhū l-Nūn al-Miṣrī (d. ca. 245/859-60): Edition and Study of ms. Vollers 875d
2016-06-07

This article presents and analyzes a new source on the relationship between ḥadīth and Sufism, a juzʾ in the library of the University of Leipzig titled Juzʾ fīhi qiṣṣat al-ʿAbbās b. Ḥamza maʿa Dhī l-Nūn al-Miṣrī raḥmat Allāh ʿalayhi , “An Encounter of al-ʿAbbās b. Ḥamza with Dhū l-Nūn al-Miṣrī.” The text is an account of the visit of Abū l-Faḍl al-ʿAbbās b. Ḥamza b. Ashūsh of Nishapur (d. 288/901) to Dhū l-Nūn al-Miṣrī (d. ca 245/859-860), an influential figure in the early mystical tradition. By underlying the difference between a mainstream ḥadīth transmission and what the text calls ḥadīth al-riqāq (“heart-melting traditions”), the text helps to defend early ascetics and mystics against accusations of being “weak transmitters” of prophetical traditions.
Diagnostic tests for Niemann-Pick disease type C (NP-C): A critical review
2016-06-08

Niemann-Pick disease type C (NP-C) is a neurovisceral lysosomal cholesterol trafficking and lipid storage disorder caused by mutations in one of the two genes, NPC1 or NPC2. Diagnosis has often been a difficult task, due to the wide range in age of onset of NP-C and clinical presentation of the disease, combined with the complexity of the cell biology (filipin) laboratory testing, even in combination with genetic testing. This has led to substantial delays in diagnosis, largely depending on the access to specialist centres and the level of knowledge about NP-C of the physician in the area. In recent years, advances in mass spectrometry has allowed identification of several sensitive plasma biomarkers elevated in NP-C (e.g. cholestane-3β,5α,6β-triol, lysosphingomyelin isoforms and bile acid metabolites), which, together with the concomitant progress in molecular genetic technology, have greatly impacted the strategy of laboratory testing. Specificity of the biomarkers is currently under investigation and other pathologies are being found to also result in elevations. Molecular genetic testing also has its limitations, notably with unidentified mutations and the classification of new variants. This review is intended to increase awareness on the currently available approaches to laboratory diagnosis of NP-C, to provide an up to date, comprehensive and critical evaluation of the various techniques (cell biology, biochemical biomarkers and molecular genetics), and to briefly discuss ongoing/future developments. The use of current tests in proper combination enables a rapid and correct diagnosis in a large majority of cases. However, even with recent progress, definitive diagnosis remains challenging in some patients, for whom combined genetic/biochemical/cytochemical markers do not provide a clear answer. Expertise and reference laboratories thus remain essential, and further work is still required to fulfill unmet needs.
Communicative Success in Spatial Dialogue: The Impact of Functional Features and Dialogue Strategies
2016-06-08

This paper addresses the impact of dialogue strategies and functional features of spatial arrangements on communicative success. To examine the sharing of cognition between two minds in order to achieve a joint goal, we collected a corpus of 24 extended German-language dialogues in a referential communication task that involved furnishing a dolls’ house. Results show how successful communication, as evidenced by correct placement of furniture items, is affected by: (a) functionality of the furniture arrangement; (b) previous task experience; and (c) dialogue features such as description length and orientation information. To enhance research in this area, our ‘Dolldialogue’ corpus ( www.dolldialogue.space ) is now available as a free resource.
Harnessing Fluorine–Sulfur Contacts and Multipolar Interactions for the Design of p53 Mutant Y220C Rescue Drugs
2016-06-08

Many oncogenic mutants of the tumor suppressor p53 are conformationally unstable, including the frequently occurring Y220C mutant. We have previously developed several small-molecule stabilizers of this mutant. One of these molecules, PhiKan083, 1-(9-ethyl-9H-carbazole-3-yl)-N-methylmethanamine, binds to a mutation-induced surface crevice with a KD = 150 μM, thereby increasing the melting temperature of the protein and slowing its rate of aggregation. Incorporation of fluorine atoms into small molecule ligands can substantially improve binding affinity to their protein targets. We have, therefore, harnessed fluorine-protein interactions to improve the affinity of this ligand. Step-wise introduction of fluorines at the carbazole ethyl anchor, which is deeply buried within the binding site in the Y220C-PhiKan083 complex, led to a 5-fold increase in affinity for a 2,2,2-trifluoroethyl anchor (ligand efficiency of 0.3 kcal mol(-1) atom(-1)). High-resolution crystal structures of the Y220C-ligand complexes combined with quantum chemical calculations revealed favorable interactions of the fluorines with protein backbone carbonyl groups (Leu145 and Trp146) and the sulfur of Cys220 at the mutation site. Affinity gains were, however, only achieved upon trifluorination, despite favorable interactions of the mono- and difluorinated anchors with the binding pocket, indicating a trade-off between energetically favorable protein-fluorine interactions and increased desolvation penalties. Taken together, the optimized carbazole scaffold provides a promising starting point for the development of high-affinity ligands to reactivate the tumor suppressor function of the p53 mutant Y220C in cancer cells.