فهرست مطالب sedigheh ghasemi

The purpose of this research was the relationship between transformational leadership and collaborative management with the learning organization in Farashband schools.

The current research method was a descriptive correlational type and the research tool was the organizational learning questionnaire, creative leadership and participatory management, the validity and reliability of which have been examined and confirmed by previous researchers. The research community is all primary school teachers and The first and second secondary schools were in Farashband city, and a suitable number of classes were randomly selected from each section.

The results of the research showed that there is a significant relationship between transformational leadership and collaborative management with the learning organization in Farashband schools. Transformational leadership is correlated with organizational learning with a value of 0.873 and a coefficient of determination of 0.762 with a confidence interval of 90 percent and at the level of P<0.01. Also, there is a correlation between collaborative management and organizational learning with a value of 0.763 and a coefficient of determination of 0.582 with a confidence interval of 95 percent at the level of P < 0.001. Transformational leadership and collaborative management are significant predictors at the level (P < 0.01) for organizational learning, and among them, transformational leadership with a beta of 0.656 has a greater impact on teachers' organizational learning.

In summary, the evidence shows that transformational leadership and participatory management are positively related to organizational learning. By combining these two leadership styles, leaders can create an environment that fosters learning, innovation, and collaboration, and helps employees develop their skills and knowledge.

Heat, both in transient and steady state, changes the physical and chemical properties of concrete. In addition, the use of slag with Portland cement is very effective on development of concrete microstructure. The main products of hydration process are cement paste and slag, which plays important role in increasing concrete strength, C-S-H and C-A-Fe-H microstructures. Based on this, this paper has focused on the concrete containing varying degrees of steel slag in order to get a deeper perception of the changing behavior of C-S-H and C-A-Fe-H due to being exposed to high temperature. In this regard, 150 cubic samples of concrete with zero, 5%, 10%, 15% and 20% replacement of steel slag to Portland cement were treated for 28 days in a moisture bath. Then, all samples were exposed for 1 hour to 25 to 800 ºC. The percentage of weight change, compressive strength and cracking behavior of samples were investigated. Furthermore, in order to evaluate the microstructural behavior of test samples in different temperatures, SEM photos and EDS were used. Based on the results, the behavior of concrete samples depends on the variations of C-S-H and C-A-Fe-H microstructures under high temperature. The compressive strength of samples containing 5 to 15% steel slag increased as compared to conventional concrete sample. Based on SEM photos, the reason for this increase is higher density of C-S-H and C-A-Fe-H microstructures and FeO(OH).

Alzheimer's disease is a progressive brain dysfunction, which damages and destroys neurons and results in memory loss. Selective Alzheimer's disease indicator-1 (seladin-1) is a gene and protein that is found to be down-regulated in specific areas of the brain affected by Alzheimer's disease. Seladin-1 has neuroprotective properties and inhibits caspase-3 activity, a key mediator of apoptosis. Seladin-1 is a multi-functional protein and independently of its activity as a caspase-3 inhibitor, it acts as a cholesterol biosynthetic enzyme. Cholesterol enhances the formation of lipid rafts inhibits the production of β-amyloid in the membrane of neural cell. Cholesterol homeostasis disorder in neural cells may enhance susceptibility of cells to the toxic agents.
Studies have shown that the level of seladin-1 increases during brain development to prevent the loss of neuronal precursor cells. Estrogen and thyroid hormones stimulate the expression of seladin-1. It seems that seladin-1 may act as a mediator of these hormones.

Several investigations revealed that the activation of the innate immune system plays a crucial role in the pathogenesis of numerous diseases. The innate immune system activation occurs in response to pathogens or tissue injury via pattern-recognition receptors that recognize pathogen-associated molecular patterns. The innate immune system triggered by these interactions besides the general responses causes a specific response to pathogen. In addition, this pathogen-specific innate response affects the specificity of the adaptive immune response through directing the differentiation of T-cells into functionally distinct subtypes. Although the mechanism(s) by which different Rabies viruses induce differential immune responses are unknown, recent studies indicate that the consequence of rabies virus infection is dependent upon the rapid stimulation of innate and adaptive immunity. The responses prevent viral entry into the central nervous system (CNS), where it can escape immunity. Laboratory strains that reach the CNS can be cleared and this has obviously happened in individuals with rabies. Thus, during rabies virus infection, pattern-recognition receptors of rabies can be recognized in the periphery and the CNS.
To study these possibilities, the consequence of rabies infection in mice lacking adaptor myeloid differentiation factor 88 (MyD88) was demonstrated. Toll-like receptors (TLRs) signals, except for TLR3, activate proinflammatory reaction via the adaptor protein MYD88. Only mice lacking TLR7 displayed a marked mortality compared with MyD88 negative and control mice with deficits in both the development of peripheral immunity and rabies virus clearance from the CNS. The review demonstrated that TLR7 plays a vital role in controlling and directing of immune response against the rabies virus.

Inclusion of antioxidant sources in feed or water reduces the detrimental effects of free radicals and increases the antioxidative potential and stability of lipids in heat stressed broiler chicken. This study was conducted to examine the effect of Satureja khuzistanica essential oils (SkEO) on early postmortem and ultimate pH as well as antioxidative potential of breast muscle in broiler chicken. A total number of 720,1-d-old Arian broiler chicks were used in a 42-d trial to examine the effects of six experimental treatments consisting inclusion of 0 (control-), 200, 300, 400, 500 mg/L SkEO and 500 mg/L Polysorbate-80 (control+) in drinking water in six replicates of 20 birds each in a completely randomized blocks design. Catalase enzyme activity (by kinetic method) and glutathione peroxidase as well as superoxide dismutase activities (via Randox® kits) were measured spectrophotometerically. Lipid peroxidation also was measured in breast muscle by a chemical method with thiobarbituric acid. The breast percentage and early as well as ultimate pH of breast muscle was not differ for the birds received SkEO-treated water compared to the control birds (p>0.05). Addition of SkEO in drinking water at doses greater than 200 mg/L significantly decreased the thiobarbituric acid reactive substances values in breast muscle of the birds in comparison with the control birds (p<0.05). Catalase activity was significantly higher in breast muscle of the SkEO-treated groups than the control groups (p<0.05). Activity of glutathione peroxidase was significantly greater in the birds given 400 and 500 mg/L SkEO. Addition of SkEO into water up to 400 mg/L increased superoxide dismutase activity in breast muscle of the treated birds compared to the control birds. It was concluded that supplementation of drinking water with SkEO elevates the antioxidative potential and increases the lipid stability of breast muscle in heat stressed male broiler chicken.

Epilepsy is the most common disorder of the central nerves system. Studies showed that carbamazepine has anti-epileptic effects. However, there is no evidence whether carbamazepine protect seizure-induced neuronal injury. In this study, the effects of carbamazepine were evaluated on cell injury observed in pentylenetetrazole (PTZ) model of seizure in the rat brain.
The convulsive behaviour and histological evaluation were performed in age- and weight-matched rats, which were divided into five groups: 1.control group: without any intervention, 2. PTZ group: after PTZ injection (40 mg/ kg), 3. Sham group: vehicles were injected 30 min before PTZ injection (40 mg/ kg), 4. Treatment group 1: carbamazepine (10 mg/kg) was injected 30 min before PTZ injection, 5. Treatment group 2: carbamazepine (40 mg/kg) was injected 30 min before PTZ injection.
Carbamazepine significantly decreased production of the dark neurons in the hippocampal CA1 and CA3 areas and the temporal cortex after PTZ-induced seizure compared to PTZ and sham groups. Density of dark neurons in treatment groups was significantly higher than control group.
The results showed that carbamazepine acts as a neuroprotective substance after seizure attacks.

Multiple sclerosis (MS) is an autoimmune disease of central nervous system that is characterized by the progressive loss of myelin. In addition to immunoregulatory properties, novel MS therapies promote myelin repair activities. Mesenchymal stem cells (MSCs) have been viewed as a potent tool for regenerative and immunosuppressive functions, indicating a potential therapy for MS. MSCs have immunological functions which are exerted by direct cell-to-cell contacts, secretion of stimulatory and inhibitory cytokines, and/or a combination of both mechanisms. Therefore, these cells can inhibit differentiation and proliferation of T-cell and stimulate the Th2 and regulatory T-cells through inhibitory effects on the immune system.
In the current review, we discuss the mechanisms underlying the immunomodulatory effect of MSCs in different experimental models of MS.