Emergent non-consumptive predator effects alter habitat colonization by mosquitoes

Top-down consumptive control (suppression) is an important driver of populations and communities of prey organisms. Diverse predator assemblages often yield non-linear suppression with respect to constituent species’ effects (emergence); most often diversity enhances suppression. Predators also affect prey organisms non-consumptively through changes in prey physiological, physical, spatial, temporal, and behavioral responses to predators. Role of predator diversity in non-consumptive response by prey is relatively un-studied. Role of predator diversity in shaping prey populations and communities through habitat colonization is a novel question

Intraseasonal characterization of tropospheric O3 in the North of the Buenos Aires Province: determining four months cycle and teleconnection evidence

Tropospheric ozone (O3T) is a secondary pollutant whose formation involved primarily solar radiation, NOx and volatile organic compounds. The North of the Buenos Aires Province has great agricultural-industrial activity; therefore, O3T study is an important issue in the area. In this paper, we present the first results tend to estimate and characterize O3T in San Nicol\'as de los Arroyos, North of Buenos Aires. Due to a lack of in situ data, we analyse the observations of the instrument OMI (Ozone Monitoring Instrument) of land remote sensing satellite AURA (GSFC/NASA). The data cover the years 2004-2013. Applying the multitaper technique (MTM), very suitable for short and noisy data series, spectral analysis is performed on a grid corresponding 1{\deg} in latitude by 1.5{\deg} in longitude, centred South of the Province of Santa Fe. The most remarkable result is the emergence of a significant peak (95%) of four months cycle. To test the validity of this signal in San Nicol\'as, daily solar radiation data (Q) were analysed in the area. The application of MTM to the daily values of Q, yields a spectral peak of 120 days. It is concluded that atmospheric opacity on the site has four months variations that modify the solar radiation at the troposphere, and consequently, the production rate of O3T. Evidence that these variations are due to teleconnection process originated in the Maritime Continent are presented.Comment: Conference paper presented at AFA (Asociaci\'on F\'isica Argentina), Bariloche, Argentina, September 2013; as a part of bigger paper to be submitted to an Earth Sciences Journa

JIST: just-in-time scheduling translation for parallel processors

The application fields of bytecode virtual machines and VLIW processors overlap in the area of embedded and mobile systems, where the two technologies offer different benefits, namely high code portability, low power consumption and reduced hardware cost. Dynamic compilation makes it possible to bridge the gap between the two technologies, but special attention must be paid to software instruction scheduling, a must for the VLIW architectures. We have implemented JIST, a Virtual Machine and JIT compiler for Java Bytecode targeted to a VLIW processor. We show the impact of various optimizations on the performance of code compiled with JIST through the experimental study on a set of benchmark programs. We report significant speedups, and increments in the number of instructions issued per cycle up to 50% with respect to the non-scheduling version of the JITcompiler. Further optimizations are discussed

libVersioningCompiler: An easy-to-use library for dynamic generation and invocation of multiple code versions

We present libVersioningCompiler, a C++ library designed to support the dynamic generation of multiple versions of the same compute kernel in a HPC scenario. It can be used to provide continuous optimization, code specialization based on the input data or on workload changes, or otherwise to dynamically adjust the application, without the burden of a full dynamic compiler. The library supports multiple underlying compilers but specifically targets the llvm framework.We also provide examples of use, showing the overhead of the library, and providing guidelines for its efficient use

Early intestinal perforation secondary to congenital mesenteric defects

Gastrointestinal perforation (GIP) in preterm neonates may be idiopathic, due to necrotizing enterocolitis (NEC), or mechanical obstruction. The predominant cause of GIP in the neonatal period is NEC. Differential diagnosis with congenital malformations, including mesenteric defects leading to internal hernias, is mandatory if the onset is early. We describe two newborns with trans-mesenteric herniation resulting in GIP, and we discuss the presence of possible additional risk factors such as prematurity and predisposing vascular disruption in connective tissue disorders (Ehlers-Danlos syndrome), twinning, and use of assisted reproductive technologies. These cases prompted us to review our exploratory laparotomies performed for intestinal obstruction, complicated/or not with perforation, to identify the frequency of neonatal trans-mesenteric hernias in a referral hospital. The prevalence of GIP and of internal hernia was 25% and 3.3%, respectively. In conclusion, time-onset and particular conditions associated with GIP should lead to a high index of suspicion for internal hernias in order to achieve appropriate diagnosis and therapy

The geometrical nature of optical resonances : from a sphere to fused dimer nanoparticles

We study the electromagnetic response of smooth gold nanoparticles with shapes varying from a single sphere to two ellipsoids joined smoothly at their vertices. We show that the plasmonic resonance visible in the extinction and absorption cross sections shifts to longer wavelengths and eventually disappears as the mid-plane waist of the composite particle becomes narrower. This process corresponds to an increase of the numbers of internal and scattering modes that are mainly confined to the surface and coupled to the incident field. These modes strongly affect the near field, and therefore are of great importance in surface spectroscopy, but are almost undetectable in the far field

Cognitive Functions and White Matter Tract Damage in Amyotrophic Lateral Sclerosis: A Diffusion Tensor Tractography Study

BACKGROUND AND PURPOSE: ALS is predominantly a disease of the motor system, but cognitive and behavioral symptoms also are observed. DT MR imaging is sensitive to microstructural changes occurring in WM tracts of patients with ALS. In this study, we investigated the association between cognitive functions and extramotor WM tract abnormalities in ALS patients. MATERIALS AND METHODS: DT MR imaging was obtained from 16 nondemented patients with ALS and 15 healthy controls. Patients with ALS underwent a neuropsychologic and behavioral evaluation. DT tractography was used to asses the integrity of the CST, corpus callosum, and the major long-range association tracts. The relationship between DT MR imaging metrics and cognitive functions was tested by using linear model analyses, adjusting for age and clinical disability. RESULTS: Eleven patients (69%) scored below the fifth percentile in at least 1 cognitive test, and 2 of them had a mild executive impairment. Performances at tests assessing attention and executive functions correlated with DT MR imaging metrics of the corpus callosum, CST, and long association WM tracts bilaterally, including the cingulum, inferior longitudinal, inferior fronto-occipital, and uncinate fasciculi. Verbal learning and memory test scores were associated with fornix DT MR imaging values, whereas visual-spatial abilities correlated with left uncinate fractional anisotropy. CONCLUSIONS: WM tract degeneration is associated with neuropsychologic deficits in patients with ALS. DT tractography holds promise to gain insight into the role of the brain WM network abnormalities in the development of cognitive impairment in patients with ALS

Patterns of Brain Structural Changes in First-Contact, Antipsychotic Drug-Naïve Patients with Schizophrenia

BACKGROUND AND PURPOSE: Previous studies have suggested that structural changes do occur in the brain of patients with schizophrenia compared with healthy control participants. However, findings from such studies are inconclusive, probably because of the different methodologic approaches, the clinical heterogeneity of patient samples, and also the fact that patients enrolled were treated with antipsychotic drugs. The aim of this study was to investigate brain GM volumes and intrinsic structural WM changes in first-contact, antipsychotic drug-naive patients with schizophrenia. MATERIALS AND METHODS: A total of 43 first-contact, drug-naive, patients with schizophrenia and 17 age-matched control participants were studied. All participants underwent T1-weighted MR imaging and DTI scans. Voxel-based morphometry and tract-based spatial statistics were used to compare GM volumes and WM DTI metrics between groups. MR imaging measures were correlated with the duration of the untreated psychosis and the clinical positive and negative symptoms. RESULTS: Compared with control participants, patients with schizophrenia showed smaller volumes of the temporal, parietal, and occipital GM, and a pattern of decreased mean diffusivity and increased fractional anisotropy in the brain stem and cerebellum bilaterally, interhemispheric and cortico-cortical connections bilaterally, and right anterior and posterior limb of the internal capsule. In patients, decreased mean diffusivity and increased fractional anisotropy in several brain regions were related to a longer duration of the untreated psychosis and the severity of positive symptoms. CONCLUSIONS: First-contact, drug-naive, patients with schizophrenia present with volumetric and DTI changes, which correlated with their clinical features. This study increases our knowledge on the neural networks involved in the pathophysiologic mechanisms of schizophrenia

Effectiveness and safety of virtual reality rehabilitation after stroke: an overview of systematic reviews

Background: Virtual reality (VR) is an innovative neurorehabilitation modality that has been variously examined in systematic reviews. We assessed VR effectiveness and safety after cerebral stroke. Methods: In this overview of systematic reviews, we searched eleven databases (Cochrane Database of Systematic Reviews, EMBASE, MEDLINE, SCOPUS, ISI Web of Science, CINAHL, PsycINFO, Pedro, Otseeker, Healthevidence.org, Epistemonikos) and grey literature from inception to January 17, 2023. Studies eligible for inclusion were systematic reviews published in English that included adult patients with a clinical diagnosis of stroke (acute to chronic phase) undergoing any kind of immersive, semi-immersive or non-immersive VR intervention with or without conventional therapy versus conventional therapy alone. The primary outcome was motor upper limb function and activity. The secondary outcomes were gait and balance, cognitive and mental function, limitation of activities, participation, and adverse events. We calculated the degree of overlap between reviews based on the corrected covered area (CCA). Methodological quality was assessed using the A MeaSurement Tool to Assess systematic Reviews (AMSTAR 2) and the Certainty of Evidence (CoE) using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Discordances between results were examined using a conceptual framework based on the Jadad algorithm. This overview is registered with PROSPERO, CRD42022329263. Findings: Of the 58 reviews included (n = 345 unique primary studies), 42 (72.4%) had conducted meta-analysis. More than half of the reviews (58.6%) were published between 2020 and 2022 and many (77.6%) were judged critically low in quality by AMSTAR 2. Most reported the Fugl Meyer Assessment scale (FMA-UE) to measure upper limb function and activity. For the primary outcome, there was a moderate overlap of primary studies (CCA 9.0%) with discordant findings. Focusing on upper limb function (FMA-UE), VR with or without conventional therapy seems to be more effective than conventional therapy alone, with low to moderate CoE and probable to definite clinical relevance. For secondary outcomes there was uncertainty about the superiority or no difference between groups due to substantial heterogeneity of measurement scales (eg, methodological choices). A few reviews (n = 6) reported the occurrence of mild adverse events. Interpretation: Current evidence suggests that multiple meta-analyses agreed on the superiority of VR with or without conventional therapy over conventional therapy on FME-UE for upper limb. Clinicians may consider embedding VR technologies into their practice as appropriate with patient's goals, abilities, and preferences. However, caution is needed given the poor methodological quality of reviews. Funding: Italian Ministry of Health