julilili42/papers huggingface dataset:
Evaluating directional cost models in navigation
2014-03-03

A common approach to social distancing in robot navigation are spatial cost functions around humans that cause the robot to prefer paths that do not come too close to humans. However, in unpredictably dynamic scenarios, following such paths may produce robot behavior that appears confused. The concept of directional costs in cost functions [9] is supposed to alleviate this problem without incurring the problem of combinatorial explosions using temporal planning. With directional cost functions, a robot attempts to solve spatial conflicts by adjusting the velocity instead of the path, where possible. To complement results from simulations, in this paper we describe a user study we conducted with a PR2 robot and human participants to evaluate the new cost function type. The study shows that the real robot behavior is similar to the observations in simulation, and that participants rate the robot behavior less confusing with the adapted cost model. The study also shows other important behavior cues that can influence motion legibility.
Pitfalls in comparing modern hair and fossil bone collagen C and N isotopic data to reconstruct ancient diets: a case study with cave bears (Ursus spelaeus)
2014-03-03

Stable isotope analyses provide one of the few means to evaluate diet of extinct taxa. However, interpreting isotope data from bone collagen of extinct animals based on isotopic patterns in different tissues of modern animal proxies is precarious. For example, three corrections are needed before making comparisons of recent hair and ancient bone collagen: calibration of carbon-13 variations in atmospheric CO2, different isotopic discrimination between diet-hair keratin and diet-bone collagen, and time averaging of bone collagen versus short-term record in hair keratin. Recently, Robu et al. [Isotopic evidence for dietary flexibility among European Late Pleistocene cave bears (Ursus spelaeus). Can J Zool. 2013;91:227-234] published an article comparing extant carbon (δ(13)C) and nitrogen (δ(15)N) stable isotopic data of European cave bear bone collagen with those of Yellowstone Park grizzly bear hair in order to test the prevailing assumption of a largely vegetarian diet among cave bears. The authors concluded that cave bears were carnivores. This work is unfortunately unfounded as the authors failed to consider the necessary corrections listed above. When these corrections are applied to the Romanian cave bears, these individuals can be then interpreted without involving consumption of high trophic-level food, and environmental changes are probably the reason for the unusual isotopic composition of these cave bears in comparison with other European cave bears, rather than a change of diet. We caution researchers to pay careful attention to these factors when interpreting feeding ecology of extinct fauna using stable isotope techniques.
Goal-predictability vs. trajectory-predictability
2014-03-03

With the work at hand we investigate the legibility factors goal-predictability and trajectory-predictability in a human-robot path crossing scenario and their correlation with other HRI properties like safety, comfort, and reliability in order to assess which factor is more important for a safe and comfortable interaction.
23-Year-Old Female with an Inflammatory Myofibroblastic Tumour of the Breast: A Case Report and a Review of the Literature
2014-03-04

<b>Purpose:</b> Inflammatory myofibroblastic tumours (IMT) are a subcategory of inflammatory pseudotumours (IPT). They arise most commonly in the abdominopelvic region, lung and retroperitoneum, but virtually any anatomical site may be involved. Predominantly children and adolescents are affected and there is a tendency for local recurrence. In the literature up to the present, 20 patients have been reported with an IPT/IMT of the breast. We would like to present another patient with this unusual tumour entity of the breast and discuss the literature. <b>Patient and Examinations:</b> A 23-year-old woman presented with a painless lump in her left breast. There was no history of breast cancer in her family. Sonography showed a hypoechoic heterogeneous solid mass with irregular margins. A core needle biopsy revealed a tumour of high cellularity and a densely collagenous background. Immunohistochemically, the spindle-shaped cells were immunoreactive to smooth muscle actin and ALK-1 protein. Additional FISH analysis proved ALK rearrangements on chromosome 2p23 leading to the diagnosis of an IMT. Wide surgical excision was performed with no evidence of local recurrence after 12 months. <b>Conclusion:</b> Three of the above mentioned 20 patients with IMT/IPT of the breast developed a recurrent tumour, none presented with distant metastasis. A significant recurrence rate of 15 % leads to a clinically and sonographically close follow-up in these patients.
Cyr61 activates retinal cells and prolongs photoreceptor survival in rd1 mouse model of retinitis pigmentosa
2014-03-04

Abstract Subretinal injections with glial cell line‐derived neurotrophic factor ( GDNF ) rescue morphology as well as function of rod cells in mouse and rat animal models of retinitis pigmentosa. At the same time, it is postulated that this effect is indirect, mediated by activation of retinal Müller glial ( RMG ) cells. Here, we show that Cyr61/CCN1, one of the secreted proteins up‐regulated in primary RMG after glial cell line‐derived neurotrophic factor stimulation, provides neuroprotective and pro‐survival capacities: Recombinant Cyr61 significantly reduced photoreceptor ( PR ) cells death in organotypic cultures of Pde6b rd1 retinas. To identify stimulated pathways in the retina, we treated Pde6b rd1 retinal explants with Cyr61 and observed an overall increase in activated Erk1/2 and Stat3 signalling molecules characterized by activation‐site‐specific phosphorylation. To identify Cyr61 retinal target cells, we isolated primary porcine PR , RMG and retinal pigment epithelium ( RPE ) cells and exposed them separately to Cyr61. Here, RMG as well as RPE cells responded with induced phosphorylation of Erk1/2, Stat3 and Akt. In PR , no increase in phosphorylation in any of the studied proteins was detected, suggesting an indirect neuroprotective effect of Cyr61. Cyr61 may thus act as an endogenous pro‐survival factor for PR , contributing to the complex repertoire of neuroprotective activities generated by RMG and RPE cells. image We propose the following model of Cyr61 neuroprotection within the retina: Cyr61 stimulates retinal Müller glial (RMG) and retinal pigment epithelium (RPE) cells and activates PI3K/Akt, mitogen‐activated protein kinase(MAPK)/Erk and Janus kinase(JAK)/Stat‐signalling pathways in these cells. Phosphorylated Stat3 and Erk1/2 presumably translocate to the nucleus, induce transcriptional changes, which increase secretion of neuroprotective agents that protect photoreceptors (PR) from mutation‐induced death.
Membrane androgen receptor sensitive Na+/H+ exchanger activity in prostate cancer cells
2014-03-04

Membrane androgen receptors (mAR) are expressed in several tumors. mAR activation by testosterone albumin conjugates (TAC) suppresses tumor growth and migration. mAR signaling involves phosphoinositide‐3‐kinase (PI3K) and Rho‐associated protein kinase (ROCK). PI3K stimulates serum‐ and glucocorticoid‐inducible kinase SGK1, which in turn activates Na + /H + ‐exchangers (NHE). In prostate cancer cells cytosolic pH (pH i ) was determined utilizing 2′,7′‐bis‐(2‐carboxyethyl)‐5‐(and‐6)‐carboxyfluorescein‐fluorescence and NHE‐activity utilizing Na + ‐dependent cytosolic realkalinization following an ammonium pulse. TAC (100 nM) significantly increased pH i and NHE‐activity, effects abrogated by NHE1‐inhibitor cariporide (10 μM), SGK1‐inhibitors EMD638683 (50 μM) and GSK650349 (10 μM) and ROCK‐inhibitors Y‐27632 (10 μM) and fasudil (100 μM). TAC treatment rapidly and significantly increased cell volume and actin polymerization, effects abolished in the presence of cariporide. Thus, mAR‐activation activates cariporide‐sensitive Na + /H + ‐exchangers, an effect requiring SGK1 and ROCK activity.
3D simulations of disc winds extending radially self-similar MHD models
2014-03-04

Disc-winds originating from the inner parts of accretion discs are considered\\nas the basic component of magnetically collimated outflows. The only available\\nanalytical MHD solutions to describe disc-driven jets are those characterized\\nby the symmetry of radial self-similarity. However, radially self-similar MHD\\njet models, in general, have three geometrical shortcomings, (i) a singularity\\nat the jet axis, (ii) the necessary assumption of axisymmetry, and (iii) the\\nnon-existence of an intrinsic radial scale, i.e. the jets formally extend to\\nradial infinity. Hence, numerical simulations are necessary to extend the\\nanalytical solutions towards the axis, by solving the full three-dimensional\\nequations of MHD and impose a termination radius at finite radial distance. We\\nfocus here on studying the effects of relaxing the (ii) assumption of\\naxisymmetry, i.e. of performing full 3D numerical simulations of a disc-wind\\ncrossing all magnetohydrodynamic critical surfaces. We compare the results of\\nthese runs with previous axisymmetric 2.5D simulations. The structure of the\\nflow in all simulations shows strong similarities. The 3D runs reach a steady\\nstate and stay close to axisymmetry for most of the physical quantities, except\\nfor the poloidal magnetic field and the toroidal velocity which slightly\\ndeviate from axisymmetry. The latter quantities show signs of instabilities,\\nwhich, however, are confined to the region inside the fast magnetosonic\\nseparatrix surface. The forces present in the flow, both of collimating and\\naccelerating nature, are in good agreement in both the 2.5D and the 3D runs. We\\nconclude that the analytical solution behaves well also after relaxing the\\nbasic assumption of axisymmetry.\\n
Lower Plasma Creatinine and Urine Albumin in Individuals at Increased Risk of Type 2 Diabetes with Factor V Leiden Mutation
2014-03-04

The factor V Leiden (FVL) mutation is the most frequent genetic cause of venous thrombosis in Caucasians. However, protective effects have been suggested to balance the disadvantages. We have recently observed protective effects of FVL mutation on experimental diabetic nephropathy in mice as well as an association with reduced albuminuria in two human cohorts of diabetic patients. In the present study we aimed to reevaluate these findings in an independent, larger cohort of 1905 Caucasians at risk of developing type 2 diabetes and extend possible associations to earlier disease stages of nephropathy. Carriers of FVL mutation had a significantly lower urine albumin excretion (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.03</mml:mn></mml:mrow></mml:math>) and tended to have lower plasma creatinine concentrations (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.07</mml:mn></mml:mrow></mml:math>). The difference in plasma creatinine concentrations was significant after adjustment for the influencing factors: age, gender, and lean body mass (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.048</mml:mn></mml:mrow></mml:math>). These observations at a very early “disease” stage are an important extension of previous findings and suggest that modification of glomerular dysfunction by FVL mutation is relevant during very early stages of diabetic nephropathy. This makes the underlying mechanism an interesting therapeutic target and raises the question whether FVL mutation may also exert protective effects in other glomerulopathies.
2-(3-{(3R,4R)-4-Methyl-3-[methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino]piperidin-1-yl}oxetan-3-yl)acetonitrile monohydrate
2014-03-04

In the title compound, C 18 H 24 N 6 O·H 2 O, the piperidine ring adopts a chair conformation with an N—C—C—C torsion angle of 39.5 (5)° between the cis -related substituents. The pyrrole N—H group forms a water-mediated intermolecular hydrogen bond to one of the N atoms of the annelated pyrimidine ring. The water molecule connects two organic molecules and is disorderd over two positions (occupancies of 0.48 and 0.52). The crystal packing shows zigzag chains of alternating organic and water molecules running parallel to the a axis.
Ultralow-Dose Chest Computed Tomography for Pulmonary Nodule Detection
2014-03-05

Our study suggests that chest CT for the detection of pulmonary nodules can be performed with third-generation dual-source CT producing high image quality, sensitivity, and diagnostic confidence at a very low effective radiation dose of 0.06 mSv when using a single-energy protocol at 100 kVp with spectral shaping and when using advanced iterative reconstruction techniques.
Coupling brain-machine interfaces with cortical stimulation for brain-state dependent stimulation: enhancing motor cortex excitability for neurorehabilitation
2014-03-05

Motor recovery after stroke is an unsolved challenge despite intensive rehabilitation training programs. Brain stimulation techniques have been explored in addition to traditional rehabilitation training to increase the excitability of the stimulated motor cortex. This modulation of cortical excitability augments the response to afferent input during motor exercises, thereby enhancing skilled motor learning by long-term potentiation-like plasticity. Recent approaches examined brain stimulation applied concurrently with voluntary movements to induce more specific use-dependent neural plasticity during motor training for neurorehabilitation. Unfortunately, such approaches are not applicable for the many severely affected stroke patients lacking residual hand function. These patients require novel activity-dependent stimulation paradigms based on intrinsic brain activity. Here, we report on such brain state-dependent stimulation (BSDS) combined with haptic feedback provided by a robotic hand orthosis. Transcranial magnetic stimulation (TMS) of the motor cortex and haptic feedback to the hand were controlled by sensorimotor desynchronization during motor-imagery and applied within a brain-machine interface (BMI) environment in one healthy subject and one patient with severe hand paresis in the chronic phase after stroke. BSDS significantly increased the excitability of the stimulated motor cortex in both healthy and post-stroke conditions, an effect not observed in non-BSDS protocols. This feasibility study suggests that closing the loop between intrinsic brain state, cortical stimulation and haptic feedback provides a novel neurorehabilitation strategy for stroke patients lacking residual hand function, a proposal that warrants further investigation in a larger cohort of stroke patients.
Ex vivo dissection of optogenetically activated mPFC and hippocampal inputs to neurons in the basolateral amygdala: implications for fear and emotional memory
2014-03-05

Many lines of evidence suggest that a reciprocally interconnected network comprising the amygdala, ventral hippocampus (vHC), and medial prefrontal cortex (mPFC) participates in different aspects of the acquisition and extinction of conditioned fear responses and fear behavior. This could at least in part be mediated by direct connections from mPFC or vHC to amygdala to control amygdala activity and output. However, currently the interactions between mPFC and vHC afferents and their specific targets in the amygdala are still poorly understood. Here, we use an ex-vivo optogenetic approach to dissect synaptic properties of inputs from mPFC and vHC to defined neuronal populations in the basal amygdala (BA), the area that we identify as a major target of these projections. We find that BA principal neurons (PNs) and local BA interneurons (INs) receive monosynaptic excitatory inputs from mPFC and vHC. In addition, both these inputs also recruit GABAergic feedforward inhibition in a substantial fraction of PNs, in some neurons this also comprises a slow GABAB-component. Amongst the innervated PNs we identify neurons that project back to subregions of the mPFC, indicating a loop between neurons in mPFC and BA, and a pathway from vHC to mPFC via BA. Interestingly, mPFC inputs also recruit feedforward inhibition in a fraction of INs, suggesting that these inputs can activate dis-inhibitory circuits in the BA. A general feature of both mPFC and vHC inputs to local INs is that excitatory inputs display faster rise and decay kinetics than in PNs, which would enable temporally precise signaling. However, mPFC and vHC inputs to both PNs and INs differ in their presynaptic release properties, in that vHC inputs are more depressing. In summary, our data describe novel wiring, and features of synaptic connections from mPFC and vHC to amygdala that could help to interpret functions of these interconnected brain areas at the network level.
Decision-Related Activity in Sensory Neurons May Depend on the Columnar Architecture of Cerebral Cortex
2014-03-05

Many studies have reported correlations between the activity of sensory neurons and animals' judgments in discrimination tasks. Here, we suggest that such neuron-behavior correlations may require a cortical map for the task relevant features. This would explain why studies using discrimination tasks based on disparity in area V1 have not found these correlations: V1 contains no map for disparity. This scheme predicts that activity of V1 neurons correlates with decisions in an orientation-discrimination task. To test this prediction, we trained two macaque monkeys in a coarse orientation discrimination task using band-pass-filtered dynamic noise. The two orientations were always 90° apart and task difficulty was controlled by varying the orientation bandwidth of the filter. While the trained animals performed this task, we recorded from orientation-selective V1 neurons ( n = 82, n = 31 for Monkey 1, n = 51 for Monkey 2). For both monkeys, we observed significant correlation (quantified as “choice probabilities”) of the V1 activity with the monkeys' perceptual judgments (mean choice probability 0.54, p = 10 −5 ). In one of these animals, we had previously measured choice probabilities in a disparity discrimination task in V1, which had been at chance (0.49, not significantly different from 0.5). The choice probabilities in this monkey for the orientation discrimination task were significantly larger than those for the disparity discrimination task ( p = 0.032). These results are predicted by our suggestion that choice probabilities are only observed for cortical sensory neurons that are organized in maps for the task-relevant feature.
Heterologous Expression of the Thiopeptide Antibiotic GE2270 from Planobispora rosea ATCC 53733 in Streptomyces coelicolor Requires Deletion of Ribosomal Genes from the Expression Construct
2014-03-05

GE2270 is a thiopeptide antibiotic generated by extensive posttranslational modifications of a ribosomally generated precursor peptide. Thiopeptides are especially active against Gram-positive bacteria, including methicillin resistant Staphylococcus aureus (MRSA). In this study the GE2270 biosynthetic gene cluster (pbt) from Planobispora rosea ATCC 53733 was successfully expressed in the heterologous host strain Streptomyces coelicolor M1146. Notably, exconjugants containing the pbt gene cluster could only be obtained after deletion of the major part of the ribosomal genes flanking the gene cluster. This is a striking example that genes belonging to primary metabolism can prevent the successful conjugative transfer of DNA from phylogenetic distant species and thus complicate heterologous expression of secondary metabolite gene clusters. GE2270 production in the heterologous producer strain increased after introduction of the constitutive ermE* promoter upstream of the GE2270 resistance gene tuf from P. rosea. Insertion of the inducible tcp830 promoter resulted in inducible GE2270 production. When the regulatory gene pbtR was deleted, the resulting strain ceased to produce GE2270, suggesting an essential role of PbtR as a putative transcriptional activator of GE2270 expression.
Hippocampal corticosterone impairs memory consolidation during sleep but improves consolidation in the wake state
2014-03-05

ABSTRACT We studied the interaction between glucocorticoid (GC) level and sleep/wake state during memory consolidation. Recent research has accumulated evidence that sleep supports memory consolidation in a unique physiological process, qualitatively distinct from consolidation occurring during wakefulness. This appears particularly true for memories that rely on the hippocampus, a region with abundant expression of GC receptors. Against this backdrop we hypothesized that GC effects on consolidation depend on the brain state, i.e., sleep and wakefulness. Following exploration of two objects in an open field, during 80 min retention periods rats received an intrahippocampal infusion of corticosterone (10 ng) or vehicle while asleep or awake. Then the memory was tested in the hippocampus‐dependent object‐place recognition paradigm. GCs impaired memory consolidation when administered during sleep but improved consolidation during the wake retention interval. Intrahippocampal infusion of GC or sleep/wake manipulations did not alter novel‐object recognition performance that does not require the hippocampus. This work corroborates the notion of distinct consolidation processes occurring in sleep and wakefulnesss, and identifies GCs as a key player controlling distinct hippocampal memory consolidation processes in sleep and wake conditions. © 2014 Wiley Periodicals, Inc.
Mineralocorticoid receptor signaling reduces numbers of circulating human naïve T cells and increases their CD62L, CCR7, and CXCR4 expression
2014-03-05

The role of mineralocorticoid receptors (MRs) in human T‐cell migration is not yet understood. We have recently shown that the MR antagonist spironolactone selectively increases the numbers of circulating naïve and central memory T cells during early sleep, which is the time period in the 24 h cycle hallmarked by predominant MR activation. To investigate whether this effect is specific to spironolactone's blockade of MRs and to study the underlying molecular mechanisms, healthy humans were given the selective MR‐agonist fludrocortisone or placebo and numbers of eight T‐cell subsets and their CD62L and CXCR4 expression were analyzed. Fludrocortisone selectively reduced counts of naïve CD4 + , central memory CD4 + , and naïve CD8 + T cells and increased CXCR4 expression on the naïve subsets. In complementing in vitro studies, fludrocortisone enhanced CXCR4 and CD62L expression, which was counteracted by spironolactone. Incubation of naïve T cells with spironolactone alone reduced CD62L and CCR7 expression. Our results indicate a regulatory influence of MR signaling on human T‐cell migration and suggest a role for endogenous aldosterone in the redistribution of T‐cell subsets to lymph nodes, involving CD62L, CCR7, and CXCR4. Facilitation of T‐cell homing following sleep‐dependent aldosterone release might thus essentially contribute to sleep's well‐known role in supporting adaptive immunity.
A general decomposition formula with interaction effects
2014-03-05

This note presents a general way to decompose differences over time or between objects into the ceteris paribus effects and the interaction effects of an arbitrary number of factors. The decomposition addresses the issue of interaction effects between factors which have been neglected in the decomposition literature. It has the additional advantage of being path-independent and aggregation consistent. An empirical application studying distributional change demonstrates that interaction effects may be a relevant feature of reality that is overlooked if other decomposition methods are used.