Adaptive channel selection for DOA estimation in MIMO radar

We present adaptive strategies for antenna selection for Direction of Arrival (DoA) estimation of a far-field source using TDM MIMO radar with linear arrays. Our treatment is formulated within a general adaptive sensing framework that uses one-step ahead predictions of the Bayesian MSE using a parametric family of Weiss-Weinstein bounds that depend on previous measurements. We compare in simulations our strategy with adaptive policies that optimize the Bobrovsky- Zaka{\i} bound and the Expected Cram\'er-Rao bound, and show the performance for different levels of measurement noise.Comment: Submitted to the 25th European Signal Processing Conference (EUSIPCO), 201

Anti-bunched photons from a lateral light-emitting diode

We demonstrate anti-bunched emission from a lateral-light emitting diode. Sub-Poissonian emission statistic, with a g$^{(2)}$(0)=0.7, is achieved at cryogenic temperature in the pulsed low-current regime, by exploiting electron injection through shallow impurities located in the diode depletion region. Thanks to its simple fabrication scheme and to its modulation bandwidth in the GHz range, we believe our devices are an appealing substitute for highly-attenuated lasers in existing quantum-key-distribution systems. Our devices outperform strongly-attenuated lasers in terms of multi-photon emission events and can therefore lead to a significant security improvement in existing quantum key distribution systems

High blood pressure in older subjects with cognitive impairment

High blood pressure and cognitive impairment often coexist in old age, but their pathophysiological association is complex. Several longitudinal studies have shown that high blood pressure at midlife is a risk factor for cognitive impairment and dementia, although this association is much less clear in old age. The effect of blood pressure lowering in reducing the risk of dementia is only borderline significant in clinical trials of older subjects, partly due to the insufficient follow-up time. Conversely, dementia onset is associated with a decrease of blood pressure values, probably secondary to neurodegeneration. Prognostic effect of blood pressure values in cognitively impaired older subjects is still unclear, with aggressive blood pressure lowering being potentially harmful in this patients category. Brief cognitive screening, coupled with simple motor assessment, are warranted to identify frail older subjects who need a more cautious approach to antihypertensive treatment. Values obtained with ambulatory blood pressure monitoring seem more useful than clinical ones to predict the outcome of cognitively impaired older subjects. Future studies should identify the most appropriate blood pressure targets in older subjects with cognitive impairment.  Riassunto Ipertensione arteriosa e decadimento cognitivo spesso coesistono in età avanzata, sebbene la loro associazione sia complessa dal punto di vista fisiopatologico. Diversi studi longitudinali hanno mostrato che elevati valori pressori in età adulta rappresentano un fattore di rischio per decadimento cognitivo e demenza, sebbene tale associazione sia molto meno chiara in età avanzata. L’effetto della terapia antiipertensiva è risultato ai limiti della significatività statistica nel ridurre il rischio di demenza negli studi di intervento su soggetti anziani, in parte a causa della durata insufficiente del follow-up. D’altra parte, l’insorgenza di demenza è associata con una riduzione dei valori pressori, probabilmente secondaria alla neurodegenerazione. L’effetto prognostico dei valori pressori in anziani con decadimento cognitivo non è stato ancora chiarito, in presenza di un possibile effetto dannoso di un trattamento antiipertensivo aggressivo in questa categoria di pazienti. Un breve screening cognitivo, associato con una semplice valutazione motoria, è raccomandato per identificare gli anziani fragili, che necessitano di un approccio più cauto alla terapia antiipertensiva. I risultati del monitoraggio della pressione arteriosa nelle 24 ore sembrano più utili della misurazione clinica per predire la prognosi degli anziani cognitivamente compromessi. Studi futuri dovrebbero identificare gli obiettivi pressori più appropriati nel trattamento di anziani con decadimento cognitivo

Biomarkers of Alzheimer's Disease: From Central Nervous System to Periphery?

Alzheimer's Disease (AD) is the most frequent form of dementia and represents one of the main causes of disability among older subjects. Up to now, the diagnosis of AD has been made according to clinical criteria. However, the use of such criteria does not allow an early diagnosis, as pathological alterations may be apparent many years before the clear-cut clinical picture. An early diagnosis is even more valuable to develop new treatments, potentially interfering with the pathogenetic process. During the last decade, several neuroimaging and cerebrospinal fluid (CSF) parameters have been introduced to allow an early and accurate detection of AD patients, and, recently, they have been included among research criteria for AD diagnosis. However, their use in clinical practice suffers from limitations both in accuracy and availability. The increasing amount of knowledge about peripheral biomarkers will possibly allow the future identification of reliable and easily available diagnostic tests

Development of synthetic selfish elements based on modular nucleases in Drosophila melanogaster.

Selfish genes are DNA elements that increase their rate of genetic transmission at the expense of other genes in the genome and can therefore quickly spread within a population. It has been suggested that selfish elements could be exploited to modify the genome of entire populations for medical and ecological applications. Here we report that transcription activator-like effector nuclease (TALEN) and zinc finger nuclease (ZFN) can be engineered into site-specific synthetic selfish elements (SSEs) and demonstrate their transmission of up to 70% in the Drosophila germline. We show here that SSEs can spread via DNA break-induced homologous recombination, a process known as 'homing' similar to that observed for homing endonuclease genes (HEGs), despite their fundamentally different modes of DNA binding and cleavage. We observed that TALEN and ZFN have a reduced capability of secondary homing compared to HEG as their repetitive structure had a negative effect on their genetic stability. The modular architecture of ZFNs and TALENs allows for the rapid design of novel SSEs against specific genomic sequences making them potentially suitable for the genetic engineering of wild-type populations of animals and plants, in applications such as gene replacement or population suppression of pest species

Lasing in planar semiconductor diodes

We present a planar laser diode based on a simple fabrication scheme compatible with virtually any geometry accessible by standard semiconductor lithography technique. We show that our lasers exhibit ~1 GHz -3dB-modulation-bandwidth already in this prototypical implementation. Directions for a significant speed increase are discussed

Mental health pathways from interpersonal violence to health-related outcomes in HlV-Positive sexual minorify men

Objective: We examined mental health pathways between interpersonal violence (IPV) and healthrelated outcomes in HIV-positive sexual minority men engaged with medical care. Method: HIV-positive gay and bisexual men (N ϭ 178) were recruited for this cross-sectional study from 2 public HIV primary care clinics that treated outpatients in an urban setting. Participants (M age ϭ 44.1 years, 36% non-White) filled out a computer-assisted survey and had health-related data extracted from their electronic medical records. We used structural equation modeling to test associations among the latent factors of adult abuse and partner violence (each comprising indicators of physical, sexual, and psychological abuse) and the measured variables: viral load, health-related quality of life (HRQOL), HIV medication adherence, and emergency room (ER) visits. Mediation was tested for the latent construct mental health problems, comprising depression, anxiety, symptomatology of posttraumatic stress disorder, and suicidal ideation. Results: The final model demonstrated acceptable fit, 2 (123) ϭ 157.05, p ϭ .02, CFI ϭ .95, TLI ϭ .94, RMSEA ϭ .04, SRMR ϭ .06, accounting for significant portions of the variance in viral load (13%), HRQOL (41%), adherence (7%), and ER visits (9%), as well as the latent variable mental health problems (24%). Only 1 direct link emerged: a positive association between adult abuse and ER visits. Conclusions: Findings indicate a significant role of IPV and mental health problems in the health of people living with HIV/AIDS. HIV care providers should assess for IPV history and mental health problems in all patients and refer for evidence-based psychosocial treatments that include a focus on health behaviors

Neurocognitive profile of patients with continuous flow Left Ventricular Assist Device

The increase of severe heart failure and the consequent reduction of the organ availability for transplantation has led to, in recent years, the introduction of the LVAD as replacement therapy to heart transplantation. Severe Heart Failure patients show cognitive deficits in various domains especially in executive functions, memory and speed of proceedings, due to different neurophysiopathological processes including chronic hypoperfusion and subsequent damage to hippocampal and para-hippocampal cortical areas. It is also known that these deficits improve after heart transplantation. We carried out a literature review selecting studies that analyzed the cognitive changes in patients with severe heart failure after implantation of the Continuous Flow Left Ventricular Assist Device. According to the inclusion criteria, we selected four studies since 2005 that presented a comprehensive neurocognitive assessment. The results show that the cognitive profile, with the implantation of LVAD improves in memory and executive domains, and this improvements results stable in short- medium time. The effects would also be independent of the type of flow produced by the device (pulsatile vs continuous). We believe that further studies are required to explore the relationship between LVAD and cognitive function in severe heart failure