Stable masking by H-2Dd cis ligand limits Ly49A relocalization to the site of NK cell/target cell contact.

Ly49A is an inhibitory receptor, which counteracts natural killer (NK) cell activation on the engagement with H-2D(d) (D(d)) MHC class I molecules (MHC-I) on target cells. In addition to binding D(d) on apposed membranes, Ly49A interacts with D(d) ligand expressed in the plane of the NK cells' membrane. Indeed, multivalent, soluble MHC-I ligand binds inefficiently to Ly49A unless the NK cells' D(d) complexes are destroyed. However, it is not known whether masked Ly49A remains constitutively associated with cis D(d) also during target cell interaction. Alternatively, it is possible that Ly49A has to be unmasked to significantly interact with its ligand on target cells. These two scenarios suggest distinct roles of Ly49A/D(d) cis interaction for NK cell function. Here, we show that Ly49A contributes to target cell adhesion and efficiently accumulates at synapses with D(d)-expressing target cells when NK cells themselves lack D(d). When NK cells express D(d), Ly49A no longer contributes to adhesion, and ligand-driven recruitment to the cellular contact site is strongly reduced. The destruction of D(d) complexes on NK cells, which unmasks Ly49A, is necessary and sufficient to restore Ly49A adhesive function and recruitment to the synapse. Thus, cis D(d) continuously sequesters a considerable fraction of Ly49A receptors, preventing efficient Ly49A recruitment to the synapse with D(d)+ target cells. The reduced number of Ly49A receptors that can functionally interact with D(d) on target cells explains the modest inhibitory capacity of Ly49A in D(d) NK cells. This property renders Ly49A NK cells more sensitive to react to diseased host cells.

Crystal size distribution of periclase in contact metamorphic dolomite marbles from the southern Adamello Massif, Italy

Crystal size distributions (CSD) of periclase in contact metamorphic dolomite marbles are presented for two profiles near the Cima Uzza summit in the southern Adamello Massif (Italy). The database was combined with geochemical and petrological information to deduce the controls on the periclase-forming reaction. The contact metamorphic dolomite marbles are exposed at the contact of mafic intrusive rocks and are partially surrounded by them. Brucite is retrograde and pseudomorphs spherical periclase crystals. Prograde periclase growth is the consequence of limited infiltration of water-rich fluid at T near 605C. Stable isotope data show depletion in (13)C and (18)O over a narrow region (40 cm) near the magmatic contact, whereas the periclase-forming reaction front extends up to 4 m from the contact. CSD analyses along the two profiles show that the median grain size of the periclase crystals does not change, but that there is a progressively greater distribution of grain sizes, including a greater proportion of larger grains, with increasing distance from the contact. A qualitative model, based on the textural and geochemical data, attributes these variations in grain size to changing reaction affinities along a kinetically dispersed infiltration front. This study highlights the need to invoke disequilibrium processes for metamorphic mineral growth and expands the use of CSDs to systems of mineral formation driven by fluid infiltration.

Update Regarding Disproportionate Minority Contact (DMC) Progress of Iowa Communities, December 1, 2015

The Iowa State Court Administrator’s Office (SCA) created the CASP Advisory Committee in October 2013 to develop a state plan addressing disproportionate minority contact (DMC) in the juvenile justice system. The planning was assisted with a discretionary grant awarded from the federal Office of Juvenile Justice and Delinquency Prevention (OJJDP).

Mothers' experience of their contact with their stillborn infant: an interpretative phenomenological analysis.

BACKGROUND: Guidelines surrounding maternal contact with the stillborn infant have been contradictory over the past thirty years. Most studies have reported that seeing and holding the stillborn baby is associated with fewer anxiety and depressive symptoms among mothers of stillborn babies than not doing so. In contrast, others studies suggest that contact with the stillborn infant can lead to poorer maternal mental health outcomes. There is a lack of research focusing on the maternal experience of this contact. The present study aimed to investigate how mothers describe their experience of spending time with their stillborn baby and how they felt retrospectively about the decision they made to see and hold their baby or not. METHOD: In depth interviews were conducted with twenty-one mothers three months after stillbirth. All mothers had decided to see and the majority to hold their baby. Qualitative analysis of the interview data was performed using Interpretive Phenomenological Analysis. RESULTS: Six superordinate themes were identified: Characteristics of Contact, Physicality; Emotional Experience; Surreal Experience; Finality; and Decision. Having contact with their stillborn infant provided mothers with time to process what had happened, to build memories, and to 'say goodbye', often sharing the experience with partners and other family members. The majority of mothers felt satisfied with their decision to spend time with their stillborn baby. Several mothers talked about their fear of seeing a damaged or dead body. Some mothers experienced strong disbelief and dissociation during the contact. CONCLUSIONS: Results indicate that preparation before contact with the baby, professional support during the contact, and professional follow-up are crucial in order to prevent the development of maternal mental health problems. Fears of seeing a damaged or dead body should be sensitively explored and ways of coping discussed. Even in cases where mothers experienced intense distress during the contact with their stillborn baby, they still described that having had this contact was important and that they had taken the right decision. This indicates a need for giving parents an informed choice by engaging in discussions about the possible benefits and risks of seeing their stillborn baby.

Contact force transitions in regrasp tasks of planar objects

This paper presents a simple and fast solution to the problem of finding the time variations of the forces that keep the object equilibrium when a finger is removed from a three contact point grasp or a finger is added to a two contact point grasp, assuming the existence of an external perturbation force (that can be the object weight itself). The procedure returns force set points for the control system of a manipulator device in a regrasping action. The approach was implemented and a numerical example is included in the paper to illustrate how it works.

High-pressure metamorphism in the Adula nappe - Guide to the excursion of the Swiss Society of Mineralogy and Petrology (September 29 - October 5, 1991)

1st day: Lithology and structure of the northern Adula nappe around Zervreila 2nd day: High-pressure rocks of the Suretta nappe, the middle Adula nappe and its Mesozoic cover - Eclogite near Innerferrara, Suretta nappe - Crossite-bearing prasinite from schistes lustres near Nufenen - Eclogites south of Hinterrhein, Adula nappe - Blueschists and eclogites from Neu-Wahli, Misox zone 3 days: Eclogite boudin and associated whiteschists in the uppermost Calanca valley, middle Adula nappe 4th day: Eclogites, associated metapelites and granitoid gneisses of Trescolmen, middle Adula nappe 5th day: The ultramafic-mafic suite of the Cima Lunga nappe around Cima di Gagnone 6th day: Garnet peridotites and eclogites from Alpe Arami, Cima Lunga nappe

Unifying Time to Contact Estimation and Collision Avoidance across Species

The -function and the -function are phenomenological models that are widely used in the context of timing interceptive actions and collision avoidance, respectively. Both models were previously considered to be unrelated to each other: is a decreasing function that provides an estimation of time-to-contact (ttc) in the early phase of an object approach; in contrast, has a maximum before ttc. Furthermore, it is not clear how both functions could be implemented at the neuronal level in a biophysically plausible fashion. Here we propose a new framework the corrected modified Tau function capable of predicting both -type ("") and -type ("") responses. The outstanding property of our new framework is its resilience to noise. We show that can be derived from a firing rate equation, and, as , serves to describe the response curves of collision sensitive neurons. Furthermore, we show that predicts the psychophysical performance of subjects determining ttc. Our new framework is thus validated successfully against published and novel experimental data. Within the framework, links between -type and -type neurons are established. Therefore, it could possibly serve as a model for explaining the co-occurrence of such neurons in the brain.