The effect of chronic peripheral nesfatin-1 application on blood pressure in normal and chronic restraint stressed rats: Related with circulating level of blood pressure regulators

Nesfatin is a peptide secreted by peripheral tissues, central and peripheral nervous system. It is involved in the regulation of homeostasis. Although the effects of nesfatin-1 on nutrition have been studied widely in the literature, the mechanisms of nesfatin-1 action and also relations with other physiological parameters are still not clarified well. We aimed to investigate the effect of peripheral chronic nesfatin-1 application on blood pressure regulation in normal and in rats exposed to restraint immobilization stress. In our study, three month-old male Wistar rats were used. Rats were divided into 4 groups as Control, Stress, Control+Nesfatin-1, Nesfatin-1+Stress. Angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-1, endothelial nitric oxide synthase, aldosterone, cortisol, nesfatin-1 levels were determined in plasma samples by ELISA. Our results have shown that chronic peripheral nesfatin-1 administration increases blood pressure in normal and in rats exposed to chronic restraint stress. Effect of nesfatin-1 on circulating level of angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-1, endothelial nitric oxide synthase, aldosterone and cortisol has been identified. We can conclude that elevated high blood pressure after chronic peripheral nesfatin-1 administration in rats exposed to chronic restraint stress may be related to decreased plasma level of endothelial nitric oxide synthase concentration

Geometric Quantization on the Super-Disc

In this article we discuss the geometric quantization on a certain type of infinite dimensional super-disc. Such systems are quite natural when we analyze coupled bosons and fermions. The large-N limit of a system like that corresponds to a certain super-homogeneous space. First, we define an example of a super-homogeneous manifold: a super-disc. We show that it has a natural symplectic form, it can be used to introduce classical dynamics once a Hamiltonian is chosen. Existence of moment maps provide a Poisson realization of the underlying symmetry super-group. These are the natural operators to quantize via methods of geometric quantization, and we show that this can be done.Comment: 17 pages, Latex file. Subject: Mathematical physics, geometric quantizatio

Relations between Entropies Produced in Nondeterministic Thermodynamic Processes

Landauer's erasure principle is generalized to nondeterministic processes on systems having an arbitrary number of non-symmetrical logical states. The condition that the process is applied in the same way, irrespective of the initial logical state, imposes some restrictions on the individual heat exchanges associated with each possible transition. The complete set of such restrictions are derived by a statistical analysis of the phase-space flow induced by the process. Landauer's erasure principle can be derived from and is a special case of these.Comment: 12 pages with one figure; a final major revision in presentation; physical assumptions are clarified no

Wind control on the accumulation of heavy metals in sediment of Lake Ulubat, Anatolia, Turkey

Freshwater Lake Ulubat (zmean = 1.5-2.0 m and Area = ~138 km2), NW Anatolia, Turkey was filled in by fine-to-medium-grain silts during the late Holocene. Deposition in Lake Ulubat has been 1.6 cm yr-1 for the last 50 years, but the sedimentation rate over the last ~1,600 years was lower (0.37 mm yr-1). The organic matter and carbonate contents of the infill show cyclic changes that reflect environmental fluctuations. The silt-dominated lithology and the vertically uniform heavy metal distributions are probably due to wind-controlled sedimentation in the lake. Heterogeneous mud, derived from a large, mountainous drainage basin, is deposited in the lake mostly during summer, June to October, when conditions are hot and calm. Winter months are stormier and sediments are re-suspended due to the shallow water depth and the effect of waves on the lake bottom. It is likely that re-suspended sediments, particularly fine-grained particles, together with the heavy metals, are transported out of the lake via the outlet, especially during periods of high lake level. This resuspension and removal process probably caused the lake sediments to become silt-dominated and depleted in heavy metals. The role of broad shallow lakes in sequestering sediments and heavy metals can be described more accurately when wind data are considered. Such information may also be helpful for land-use planning in downstream areas

Possible activation of the immune system by chronic peripheral nesfatin-1 application at the acute phase of ischemia/reperfusion injury

Objective: Organ transplantation is one of the clinical scenarios involving ischemia and reperfusion process. Ischemia/reperfusion is the pivotal mechanism of organ injury during transplantation. Thus, ischemia/reperfusion (I/R) injury is a biphasic phenomenon that can damage the graft by inflammatory responses. The hypothalamic-pituitary-adrenal (HPA) axis is the main hormonal system that is activated under the influence of stress. Normal HPA axis activity leading to the release of glucocorticoids is essential for homeostasis and survival during stress. Cortisol, a key controller of stress response, is released by the HPA axis. The disrupted release of cortisol in response to inflammation has been shown in animal models. Nesfatin-1 is a peptide involved in the regulation of homeostasis and has anti-inflammatory as well as anti-ischemic properties. Therefore, we aimed to identify the effect of chronic peripheral nesfatin-1 application on the plasma level of cortisol in a rat model of intestinal I/R-based stress. Materials and Methods: Two-month-old 28 Wistar Albino male rats that weighed an average of 200–250 g were used and were randomly divided into the following four experimental groups (n=7): laparotomy, I/R, nesfatin-1+laparotomy, nesfatin-1+I/R. Blood samples were collected in tubes with EDTA. Plasma cortisol levels were analyzed by rat enzyme-linked immunosorbent assay (ELISA) kits. Results: Statistically significant decrease was found in the plasma level of cortisol in nesfatin-1+I/R group compared with I/R group (p=0.026) Conclusion: Nesfatin-1 application can inhibit anti-inflammatory responses under the early phase of intestinal I/R and support immune reactions by reducing plasma cortisol level. This effect of nesfatin-1 may also increase the rejection of grafts during transplantation period. © 2015 by Erciyes University School of Medicine

Large N limit of SO(N) gauge theory of fermions and bosons

In this paper we study the large N_c limit of SO(N_c) gauge theory coupled to a Majorana field and a real scalar field in 1+1 dimensions extending ideas of Rajeev. We show that the phase space of the resulting classical theory of bilinears, which are the mesonic operators of this theory, is OSp_1(H|H )/U(H_+|H_+), where H|H refers to the underlying complex graded space of combined one-particle states of fermions and bosons and H_+|H_+ corresponds to the positive frequency subspace. In the begining to simplify our presentation we discuss in detail the case with Majorana fermions only (the purely bosonic case is treated in our earlier work). In the Majorana fermion case the phase space is given by O_1(H)/U(H_+), where H refers to the complex one-particle states and H_+ to its positive frequency subspace. The meson spectrum in the linear approximation again obeys a variant of the 't Hooft equation. The linear approximation to the boson/fermion coupled case brings an additonal bound state equation for mesons, which consists of one fermion and one boson, again of the same form as the well-known 't Hooft equation.Comment: 27 pages, no figure

Defense against Sybil attack in the initial deployment stage of vehicular ad hoc network based on roadside unit support

In this paper, we propose two certificate mechanisms for preventing the Sybil attack in a vehicular ad hoc network (VANET): the timestamp series approach and the temporary certificate approach. We focus on an early-stage VANET when the number of smart vehicles is only a small fraction of the vehicles on the road and the only infrastructure components available are the roadside units (RSUs). Our approach does not require a dedicated vehicular public key infrastructure to certify individual vehicles but RSUs are the only components issuing certificates. The vehicles can obtain certificates by simply driving by RSUs, without the need to pre-register at a certificate authority. The timestamp series approach exploits the fact that because of the variance of the movement patterns of the vehicles, it is extremely rare that the two vehicles pass by a series of RSUs at exactly the same time points. The vehicles obtain a series of certificates signed by the RSUs, which certify their passing by at the RSU at a certain time point. By exploiting the spatial and temporal correlation between vehicles and RSUs, we can detect the Sybil attack by checking the similarity of timestamp series. In the temporary certificate-based approach, an RSU issues temporary certificates valid only in a particular area for a limited time. To guarantee that each vehicle is assigned only a single certificate, at the issuance of the first certificate, it is required that the RSU physically authenticate the vehicle. When driving by the subsequent RSUs, however, the certificate can be updated in a chained manner. By guaranteeing that each vehicle is issued a single certificate in a single area, the Sybil attack is prevented. We provide mathematical analysis and simulation for the timestamp series approach. The simulation shows that it works with a small false-positive rate in simple roadway architecture