scholarly journals A Scalable and Robust Feedback Mechanism for Adaptive Multimedia Multicast Systems

Author(s):  
Alaa Youssef ◽  
Hussein Abdel-Wahab ◽  
Kurt Maly
Author(s):  
S. Jalalah ◽  
K. Kovacs ◽  
E. Horvath

Lactotrophs, as many other endocrine cells, change their morphology in response to factors influencing their secretory activity. Secretion of prolactin (PRL) from lactotrophs, like that of other anterior pituitary hormones, is under the control of the hypothalamus. Unlike most anterior pituitary hormones, PRL has no apparent target gland which could modulate the endocrine activity of lactotrophs. It is generally agreed that PRL regulates its own release from lactotrophs via the short loop negative feedback mechanism exerted at the level of the hypothalamus or the pituitary. Accordingly, ultrastructural morphology of lactotrophs is not constant; it is changing in response to high PRL levels showing signs of suppressed hormone synthesis and secretion.By transmission electron microscopy and morphometry, we have studied the morphology of lactotrophs in nontumorous (NT) portions of 7 human pituitaries containing PRL-secreting adenoma; these lactotrophs were exposed to abnormally high PRL levels.


2018 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Dafirius Lombu ◽  
Siska Dame Tarihoran ◽  
Irwan Gulo

Generally, the database access of a website lies in the user login. When the login data is not accompanied by security techniques, it is very easily accessible by other parties. One effort that can be done to solve the problem is to encode the login data of website users based on cryptographic technique algorithm. Triangle Chain Cipher (TCC) is one of the classic cryptographic algorithms that encode data doubly and generate keys randomly along the plain. The process of encryption and decryption are interdependent to be one of the advantages of this algorithm. This algorithm will be more effective when combined with the Cipher Block Chaining (CBC) operation mode that is widely used in modern cryptographic algorithms today. The feedback mechanism between the blocks in this mode of operation is the operating advantage. This study describes how to combine the mode of operation of block chaining cipher with triangle chain cipher algorithm so that cipher data login website generated more random and difficult to find its original meaning.


2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Sami Chedhli Nighaoui

That standardized tests do not accurately assess the true competencies of minority test takers is a widely shared claim among conservative educationists. The opt-out-of-testing community has lately grown unprecedentedly vocal in several states, questioning even more seriously the accountability of the testing system altogether. This paper adopts a Critical Race Theory perspective to investigate the conceptual underpinnings of conservative criticism as well as the interpretations made popular using quantitative methodology. The key premise of this paper is that a colorblind approach to testing understates the importance of a range of unquantifiable variables, mainly the linguitic and cultural backgrounds of the test takers, in determining assessment outcome. It attempts to demonstrate where specifically standardized tests may not be used as a reliable feedback mechanism and suggests that a more flexible assessment paradigm be considered, one that engages learning quality followup to keep cultural bias to a strict minimum.          


Shore & Beach ◽  
2019 ◽  
pp. 3-14 ◽  
Author(s):  
Joshua Davis ◽  
Diana Mitsova ◽  
Tynon Briggs ◽  
Tiffany Briggs

Wave forcing from hurricanes, nor’easters, and energetic storms can cause erosion of the berm and beach face resulting in increased vulnerability of dunes and coastal infrastructure. LIDAR or other surveying techniques have quantified post-event morphology, but there is a lack of in situ hydrodynamic and morphodynamic measurements during extreme storm events. Two field studies were conducted in March 2018 and April 2019 at Bethany Beach, Delaware, where in situ hydrodynamic and morphodynamic measurements were made during a nor’easter (Nor’easter Riley) and an energetic storm (Easter Eve Storm). An array of sensors to measure water velocity, water depth, water elevation and bed elevation were mounted to scaffold pipes and deployed in a single cross-shore transect. Water velocity was measured using an electro-magnetic current meter while water and bed elevations were measured using an acoustic distance meter along with an algorithm to differentiate between the water and bed during swash processes. GPS profiles of the beach face were measured during every day-time low tide throughout the storm events. Both accretion and erosion were measured at different cross-shore positions and at different times during the storm events. Morphodynamic change along the back-beach was found to be related to berm erosion, suggesting an important morphologic feedback mechanism. Accumulated wave energy and wave energy flux per unit area between Nor’easter Riley and a recent mid-Atlantic hurricane (Hurricane Dorian) were calculated and compared. Coastal Observations: JALBTCX/NCMP emergency-response airborne Lidar coastal mapping & quick response data products for 2016/2017/2018 hurricane impact assessments


Author(s):  
Benjamin Kuipers

This chapter describes a computational view of the function of ethics in human society and discusses its application to three diverse examples. First, autonomous vehicles are individually embodied intelligent systems that act as members of society. The ethical knowledge needed by such an agent is not how to choose the lesser evil when confronted by a Deadly Dilemma, but how to recognize the upstream decision point that makes it possible to avoid the Deadly Dilemma entirely. Second, disembodied distributed intelligent systems like Google and Facebook provide valuable services while collecting, aggregating, and correlating vast amounts of information about individual users. With inadequate controls, these corporate systems can invade privacy and do substantial damage through either correct or incorrect inferences. Third, acceptance of the legitimacy of the society by its individual members depends on a general perception of fairness. Rage about unfairness can be directed at individual free-riders or at systematic inequality across the society. Ultimately, the promise of a computational approach to ethical knowledge is not simply ethics for computational devices such as robots. It also promises to help people understand the pragmatic value of ethics as a feedback mechanism that helps intelligent creatures, human and nonhuman, live together in thriving societies.


Author(s):  
Daniele Suzete Persike ◽  
Suad Yousif Al-Kass

AbstractPost-traumatic stress disorder (PTSD) is a multifaceted syndrome due to its complex pathophysiology. Signals of illness include alterations in genes, proteins, cells, tissues, and organism-level physiological modifications. Specificity of sensitivity to PTSD suggests that response to trauma depend on gender and type of adverse event being experienced. Individuals diagnosed with PTSD represent a heterogeneous group, as evidenced by differences in symptoms, course, and response to treatment. It is clear that the biochemical mechanisms involved in PTSD need to be elucidated to identify specific biomarkers. A brief review of the recent literature in Pubmed was made to explore the major biochemical mechanisms involved in PTSD and the methodologies applied in the assessment of the disease. PTSD shows pre-exposure vulnerability factors in addition to trauma-induced alterations. The disease was found to be associated with dysfunctions of the hypothalamic–pituitary–adrenal axis (HPA) and hypothalamus–pituitary–thyroid axis. Sympathetic nervous system (SNS) activity play a role in PTSD by releasing norepinephrine and epinephrine. Cortisol release from the adrenal cortex amplifies the SNS response. Cortisol levels in PTSD patients, especially women, are later reduced by a negative feedback mechanism which contributes to neuroendocrine alterations and promotes structural changes in the brain leading to PTSD. Gender differences in normal HPA responsiveness may be due to an increased vulnerability in women to PTSD. Serotonin and dopamine levels were found to be abnormal in the presence of PTSD. Mechanisms such as the induction of neuroinflammation and alterations of mitochondrial energy processing were also associated with PTSD.


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