38 research outputs found

    Design and analysis of class AB RF power amplifier for wireless communication applications

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    The Power Amplifier is the most power-consulting block among the building blocks of RF transceivers. It is still a difficult problem to design power amplifiers, especially for linear, low voltage operation. Until now power amplifiers for wireless applications is being produced almost in GaAs processes with some exceptions in LDMOS, Si BJT, and SiGe HBT. The submicron CMOS processes for power amplifiers are under research focus since CMOS offers integration for power amplifier with rest of the transceivers blocks due to its high yield. Also CMOS process is cheap. This thesis report details the design process of a class AB power amplifier for GSM wireless applications using 0.35 ”m CMOS process. The transmit frequency for GSM-1800 standard for handset applications is 1710 MHz - 1785 MHz. The power amplifier has been designed to deliver 2 W of minimum output power into a 50 Q load. The circuit-was designed and simulations indicated a peak power added efficiency of 47 %

    Pramipexole protective effect on rotenone induced neurotoxicity in mice

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    Introduction: 
Pramipexole is a new dopaminergic drug which has been approved for PD treatment. However, we tried to find a new capacity for this drug rather than symptomatic effect. 

Materials and Methods: 
A chronic rotenone model with daily oral dose of 30mg/kg was induced in mice. Pramipexole was tried in a new approach where the treatment began in the middle of rotenone course with oral dose 1mg/kg/day of pramipexole. 

Results: 
Further analysis of behavioral tests and immunohistochemistry revealed success of pramipexole in improving the rotenone intoxicated mice. 

Conclusion: 
These results showed possible beneficial effects of pramipexole against rotenone-induced neurotoxicity

    Evaluation of pain perception associated with maxillary first molars distalization in the presence of maxillary third molars versus extracted third molars using infra-zygomatic mini-screws: A randomized clinical trial

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    Aim: The purpose of this randomized clinical trial was to compare the pain associated with distalizing maxillary first molars with the presence versus extraction of unerupted third molars using infra-zygomaic mini -screws in a group of adolescent female patients. Study design: This randomized clinical trial (parallel group design) was approved by the Research Ethics Committee of the Faculty of Dentistry, Future University in Egypt Materials and methods: 30 patients requiring bilateral maxillary molar distalization using infra-zygomatic mini-implant were randomly allocated to third molar extraction (TME) or third Molar presence (TMP) groups All patients were asked to assess their pain levels on the day of the mini-implant insertion procedure and after 24 hours, 72 hours, and 1 week using a numeric pain rating scale. Additionally, Each patient completed a numeric pain rating scale form on the day of mini-screw loading, 3 days, 1 week, and 2 weeks following appliance fixation. Every patient received three copies, and the first, third, and sixth appliance activations required the same pain response. Results: At the mini-implant site, the mean pain scores in the TMP and TME on the same day for screw insertion were 5.27±2.08 and 4.89±1.99, respectively. And faded away gradually in both groups. Throughout the distalization phase, the average pain severity at the maxillary molar site on the day of mini-implant loading was 4.2±1.46 in the TMP group and 4.13±2.2 in the TME group. That subsides gradually to mild pain after one week of each appliance activation. comparable results found between both groups Conclusion: Pain experienced by the patient during maxillary molar distalization is comparable regardless of the presence or absence of the third molar. The insertion of infra-zygomatic screws caused moderate to modest discomfort in both groups. The distalization procedure was associated with mild to moderate discomfort, which progressively subsided after the loading day

    Parkinson's Disease: Is It a Toxic Syndrome?

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    Parkinson's disease (PD) is one of the neurodegenerative diseases which we can by certainty identify its pathology, however, this confidence disappeares when talking about the cause. A long history of trials, suggestions, and theories tried linking PD to a specific causation. In this paper, a new suggestion is trying to find its way, could it be toxicology? Can we—in the future—look to PD as an occupational disease, in fact, many clues point to the possible toxic responsibility—either total or partial—in causing this disease. Searching for possible toxic causes for PD would help in designing perfect toxic models in animals

    Stimuli-responsive hydrogels: smart state of-the-art platforms for cardiac tissue engineering

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    Biomedicine and tissue regeneration have made significant advancements recently, positively affecting the whole healthcare spectrum. This opened the way for them to develop their applications for revitalizing damaged tissues. Thus, their functionality will be restored. Cardiac tissue engineering (CTE) using curative procedures that combine biomolecules, biomimetic scaffolds, and cells plays a critical part in this path. Stimuli-responsive hydrogels (SRHs) are excellent three-dimensional (3D) biomaterials for tissue engineering (TE) and various biomedical applications. They can mimic the intrinsic tissues’ physicochemical, mechanical, and biological characteristics in a variety of ways. They also provide for 3D setup, adequate aqueous conditions, and the mechanical consistency required for cell development. Furthermore, they function as competent delivery platforms for various biomolecules. Many natural and synthetic polymers were used to fabricate these intelligent platforms with innovative enhanced features and specialized capabilities that are appropriate for CTE applications. In the present review, different strategies employed for CTE were outlined. The light was shed on the limitations of the use of conventional hydrogels in CTE. Moreover, diverse types of SRHs, their characteristics, assembly and exploitation for CTE were discussed. To summarize, recent development in the construction of SRHs increases their potential to operate as intelligent, sophisticated systems in the reconstruction of degenerated cardiac tissues

    Socially sensitive lactation: Exploring the social context of breastfeeding

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    Many women report difficulties with breastfeeding and do not maintain the practice for as long as intended. Although psychologists and other researchers have explored some of the difficulties they experience, fuller exploration of the relational contexts in which breastfeeding takes place is warranted to enable more in-depth analysis of the challenges these pose for breastfeeding women. The present paper is based on qualitative data collected from 22 first-time breastfeeding mothers through two phases of interviews and audio-diaries which explored how the participants experienced their relationships with significant others and the wider social context of breastfeeding in the first five weeks postpartum. Using a thematic analysis informed by symbolic interactionism, we develop the overarching theme of ‘Practising socially sensitive lactation’ which captures how participants felt the need to manage tensions between breastfeeding and their perceptions of the needs, expectations and comfort of others. We argue that breastfeeding remains a problematic social act, despite its agreed importance for child health. Whilst acknowledging the limitations of our sample and analytic approach, we suggest ways in which perinatal and public health interventions can take more effective account of the social challenges of breastfeeding in order to facilitate the health and psychological well-being of mothers and their infants
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