Symplectic connections, Noncommutative Yang Mills theory and Supermembranes

In built noncommutativity of supermembranes with central charges in eleven dimensions is disclosed. This result is used to construct an action for a noncommutative supermembrane where interesting topological terms appear. In order to do so, we first set up a global formulation for noncommutative Yang Mills theory over general symplectic manifolds. We make the above constructions following a pure geometrical procedure using the concept of connections over Weyl algebra bundles on symplectic manifolds. The relation between noncommutative and ordinary supermembrane actions is discussed.Comment: 18 page

Methylation of the Gpat2 promoter regulates transient expression during mouse spermatogenesis

Spermatogenesis is a highly regulated process that involves both mitotic and meiotic divisions, as well as cellular differentiation to yield mature spermatozoa from undifferentiated germinal stem cells. Although Gpat2 was originally annotated as a glycerol-3-phospate acyltransferase by sequence homology to Gpat1 , GPAT2 is highly expressed in testis but not in lipogenic tissues and is not up-regulated during adipocyte differentiation. New data show that GPAT2 is required for the synthesis of piRNAs, a group of small RNAs that protect the germ cell genome from retrotransposable elements. In order to understand the relationship between GPAT2 and its role in the testis, we focused on Gpat2 expression during the first wave of mouse spermatogenesis. Gpat2 expression was analyzed by qPCR, in situ hybridization, immunohistochemistry and Western blot. Gpat2 mRNA content and protein expression were maximal at 15 dpp and restricted to pachytene spermatocytes. To achieve this transient expression, both epigenetic mechanisms and trans-acting factors are involved. In vitro assays showed that Gpat2 expression correlates with DNA demethylation and histone acetylation and that it is up-regulated by retinoic acid. Epigenetic regulation by DNA methylation was confirmed in vivo in germ cells by bisulfite sequencing of the Gpat2 promoter. Consistent with the initiation of meiosis at 11 dpp, methylation decreased dramatically. Thus, Gpat2 is expressed at a specific stage of spermatogenesis, consistent with piRNA synthesis and meiosis I prophase, and its on-off expression pattern responds predominantly to epigenetic modifications.Fil: Garcia Fabiani, Maria Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Montanaro, Mauro Aldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Lacunza, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Inmunológicas Básicas y Aplicadas; ArgentinaFil: Cattaneo, Elizabeth Renee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Coleman, Rosalind A.. University of North Carolina; Estados UnidosFil: Pellon Maison, Magali. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Gonzalez-Baró; MR. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata ; Argentin

Towards the deformation quantization of linearized gravity

We present a first attempt to apply the approach of deformation quantization to linearized Einstein's equations. We use the analogy with Maxwell equations to derive the field equations of linearized gravity from a modified Maxwell Lagrangian which allows the construction of a Hamiltonian in the standard way. The deformation quantization procedure for free fields is applied to this Hamiltonian. As a result we obtain the complete set of quantum states and its discrete spectrum.Comment: 13 pages, no figures **preliminary entry **

Serotonin transporter in the temporal lobe, hippocampus and amygdala in SUDEP

Several lines of evidence link deficient serotonin function and SUDEP. Chronic treatment with serotonin reuptake inhibitors (SRIs) reduces ictal central apnoea, a risk factor for SUDEP. Reduced medullary serotonergic neurones, modulators of respiration in response to hypercapnia, were reported in a SUDEP post-mortem series. The amygdala and hippocampus have high serotonergic innervation and are functionally implicated in seizure-related respiratory dysregulation. We explored serotonergic networks in mesial temporal lobe structures in a surgical and post-mortem epilepsy series in relation to SUDEP risk. We stratified 75 temporal lobe epilepsy patients with hippocampal sclerosis (TLE/HS) into high (16), medium (11) and low risk (48) groups for SUDEP based on generalised seizure frequency. We also included the amygdala in 35 post-mortem cases, including SUDEP (17), epilepsy controls (10) and non-epilepsy controls (8). The immunohistochemistry labelling index (LI) and axonal length (AL) of serotonin transporter (SERT)-positive axons were quantified in 13 regions of interest with image analysis. SERT LI was highest in amygdala and subiculum regions. In the surgical series, higher SERT LI was observed in high risk than low risk cases in the dentate gyrus, CA1 and subiculum (p<0.05). In the post-mortem cases higher SERT LI and AL was observed in the basal and accessory basal nuclei of the amygdala and peri-amygdala cortex in SUDEP compared to epilepsy controls (p<0.05). Patients on SRI showed higher SERT in the dentate gyrus (p<0.005) and CA4 (p<0.05) but there was no difference in patients with or without a psychiatric history. Higher SERT in hippocampal subfields in TLE/HS cases with SUDEP risk factors and higher amygdala SERT in post-mortem SUDEP cases than epilepsy controls supports a role for altered serotonergic networks involving limbic regions in SUDEP. This may be of functional relevance through reduced 5-HT availability

Preliminary results from seismic monitoring at Nyiragongo Volcano (Democratic Republic Of Congo) through telemetered seismic network, Goma Volcano Observatory

Following the January 17, 2002 catastrophic eruption of the Nyiragongo Volcano (Democratic Republic of Congo) located in the western branch of the East African Rift, a great effort has been devoted to the seismic surveillance of this volcanic area. The 2002 eruption destroyed one/tenth of the city of Goma, leaving more than 100,000 homeless. In order to correctly monitor the seismic activity at Nyiragongo volcano for both scientific and civil defence purposes, the Istituto Nazionale di Geofisica e Vulcanologia in cooperation with GVO (Goma Volcanological Observatory), between November 2003 and May 2004 installed a new telemetered seismic network consisting of seven digital stations. The network is operational and seismic signals are continuously recorded at the GVO. In this study, we focus mainly on two aspects: (1) the deployment, in the field, of this new digital seismic network and the related real-time data acquisition system, and (2) the first results from a preliminary data analysis based on 6-month seismic recordings. Based on the waveforms and spectral analysis, long-period and very long period events (both, tectonic and volcanic-tectonic earthquakes), have been detected. Furthermore, we succeeded in locating more than 100 earthquakes. These results should strongly encourage the use of such a network data for seismotectonic studies of the area.Published117-1271.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveN/A or not JCRreserve

Preliminary results from seismic monitoring at Nyiragongo Volcano through telemetered seismic network, Goma Volcano Observatory (Gvo, Democratic Republic Of Congo).

Following the catastrophic eruption of Volcano Nyiragongo on January 17, 2002, a great effort has been devoted to the seismic surveillance of volcanoes Nyiragongo and Nyamuragira located at the North of Lake Kivu in the Western branch of the east African rift. The relatively small loss of life in the January 2002 eruption (less than 100 deaths in a population of 500,000) was remarkable, and psychological stress was reportedly the main health consequence in the aftermath of the eruption. In fact, after 2002 january eruption, which was triggered by tectonic spreading of the Kivu rift causing the ground to fracture and allow lava to flow from ground fissures out of the crater lava lake and possibly from a deeper conduit nearer Goma, was installed a telemetered seismic network of 6 permanent stations. Scientists agree that volcano monitoring and contingency planning are essential for forecasting and responding to future trends.OGS TRIESTEUnpublishedROMA1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attiveope

Comportamento diferencial do estado nutricional de cultivares de mamoeiros avaliados por meio das análises de macronutrientes em limbos e pecíolos foliares em condições edafoclimáticas do Amazonas.

Iniciou-se este trabalho com o objetivo geral de introduzir, avaliar e identificar cultivares adaptadas às condições de clima e solo do Estado do Amazonas, portadoras de elevado potencial produtivo e de características agronômicas favoráveis à qualidade, para futuras recomendações aos produtores. Nesta etapa, o objetivo específico foi avaliar o comportamento diferencial de quinze cultivares de mamoeiros em relação aos teores de macronutrientes nos tecidos do limbo foliar e do pecíolo, bem como comparar os teores entre essas duas partes da folha amostradas

The monitoring of seismic activity at Nyiragongo volcano through telemetered seismic network Goma Volcano Observatory (Democratic Republic of the Congo)

The eruption, in January 2002, of Mount Nyiragongo in eastern Congo, and the humanitarian disaster that followed in its wake, underlined the critical importance of accurate seismology to predict when such events will take place. Thus, a seismic telemeterd network, with centre in Goma Observatory, was built across Virunga area to help the moniotring of Volcano. Mount Nyiragongo is a volcano in the Virunga Mountains associated with the Great Rift Valley. The most prominent feature of the Democratic Republic of Congo's geology is the Western Rift Zone (WRZ), which runs through its eastern border regions and neighbouring countries (e.g. Uganda, Rwanda, Burundi, Tanzania) between 28°E to 32°E and 4°N to 12°S. The WRZ extends over a 1600 km arc, including lakes Albert, Eduard, Kivu and Tanganyika, until it joins the eastern branch. The Western Rift Valley of Africa has experienced severe earthquakes and volcanic eruptions in recent historical times. Earthquakes with magnitude >=6 are not frequent, but may cause significant destruction. They occur mostly in DRC and neighbouring countries (e.g. Uganda and Tanzania). In 1991, IAVCEI selected the Nyiragongo volcano as the ‘African decade volcano’ for the International Decade of Natural Disaster Reduction (IDNDR) program. Nyiragongo is located about 20 km north of Lake Kivu and 15 km north of Goma, a city of about 500,000 inhabitants. Goma is twinned to Gisenyi in Rwanda, which has a population of about 100,000. Several small villages are also located on the flank of the volcano. Population growth and poor or non-existent planning has led to relatively uncontrolled use of land for building, and the development of sites vulnerable to earthquake and/or volcanic risk.EUROPEAN CENTER FOR GEODYNAMICS AND SEISMOLOGY Royal Museum for Central Africa, B National Museum of Nat. History, LUnpublishedLuxembourg1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope

Review of low-cost sensors for indoor air quality: Features and applications

Humans spend the majority of their time indoors, where they are potentially exposed to hazardous pollutants. Within this context, over the past few years, there has been an upsurge of low-cost sensors (LCS) for the measurement of indoor air pollutants, motivated both by recent technological advances and by increased awareness of indoor air quality (IAQ) and its potential negative health impacts. Although not meeting the performance requirements for reference regulatory-equivalent monitoring indoors, LCS can provide informative measurements, offering an opportunity for high-resolution monitoring, emission source identification, exposure mitigation and managing IAQ and energy efficiency, among others. This article discusses the strengths and limitations that LCS offer for applications in the field of IAQ monitoring; it provides an overview of existing sensor technologies and gives recommendations for different indoor applications, considering their performance in the complex indoor environment and discussing future trends

Macrobrachium borellii Hepatopancreas Contains a Mitochondrial Glycerol-3-Phosphate Acyltransferase Which Initiates Triacylglycerol Biosynthesis

Mammals express four isoforms of glycerol-3-phosphate acyltransferase (GPAT). The mitochondrial isoform GPAT1 may have been the acyltransferase that appeared first in evolution. The hepatopancreas of the crustacean Macrobrachium borellii has a high capacity for triacylglycerol (TAG) biosynthesis and storage. In order to understand the mechanism of glycerolipid biosynthesis in M. borellii, we investigated its hepatopancreas GPAT activity. In hepatopancreas mitochondria, we identified a GPAT activity with characteristics similar to those of mammalian GPAT1. The activity was resistant to inactivation by SH-reactive N-ethylmaleimide, it was activated by polymyxin-B, and its preferred substrate was palmitoyl-CoA. The reaction products were similar to those of mammalian GPAT1. A 70-kDa protein band immunoreacted with an anti-rat liver GPAT1 antibody. Surprisingly, we did not detect high GPAT specific activity in hepato-pancreas microsomes. GPAT activity in microsomes was consistent with mitochondrial contamination, and its properties were similar to those of the mitochondrial activity. In microsomes, TAG synthesis was not dependent on the presence of glycerol-3 phosphate as a substrate, and the addition of monoacylglycerol as a substrate increased TAG synthesis 2-fold. We conclude that in M. borellii the de novo triacylglycerol biosynthetic pathway can be completed in the mitochondria. In contrast, TAG synthesis in the ER may function via the monoacylglycerol pathway