Characteristics of Silver-Hydroxyapatite/PVP Nanocomposite

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Metal nanoparticles play an important role in many different areas such as catalysis, electronics, sensors, and cancer therapy. Silver, in its many oxidation states (Ag0, Ag+, Ag2+, and Ag3+), has long been recognized as having an inhibitory effect towards many bacterial strains and microorganisms commonly present in medical and industrial processes. Silver was introduced in various materials including hydroxyapatite due to its biocompatibility. The unique size-dependent properties of nanomaterials make them superior and indispensable.

nanobiomaterials pdfIn this work, nanohydroxyapatite/poly vinylpyrrolidone composite was doped with 2 different concentrations of silver nanoparticles prepared by reduction method. Several techniques like TEM, XRD, FT-IR, and SEM with EDS were used to characterize the prepared samples. The bioactivity test (soaking in SBF) at different short time intervals was characterized by using inductively coupled plasma-optical emission spectroscopy (ICP-OES) method. It is demonstrated that silver-doped nanohydroxyapatite obviously improves the bioactivity of the apatite at the early stages of immersion. The antibacterial inhibition over 3 types of bacteria (Staphylococcus aureus, Streptococcus mutans, and Pseudomonas) is under investigation.

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Phenobarbitone Causing Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) in a Child Previously Exposed to Long-Term Phenobarbitone as an Infant

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OLYMPUS DIGITAL CAMERAAn 8 year old Chinese boy had epilepsy and global development delay associated with underlying West syndrome. He first presented with infantile spasms at 5 months of age and was treated with phenobarbitone for seizure control. Phenobarbitone was well-tolerated then and he was asymptomatic. Vigabatrin and sodium valproate were subsequently added 6 months after phenobarbitone monotherapy was started as the seizures increased in frequency. Phenobarbitone was weaned off over another 2 weeks. His seizures became well-controlled and all antiepileptic medications were discontinued from 3 years of age. 5 years later, generalised seizures recurred and sodium valproate was restarted and it was switched to Phenobarbitone 4 months later for better seizure control.

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Protection of Hospitality Employees

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Part of the problem is that hospitality operations do not admit that security and safety are concerns. Paul Moxness VP for corporate safety and security at The Rezidor Hotel Group, a Brussels-based hotel management company stated “Security still is something of a taboo in the global hotel industry.” Hawley reported Housekeepers often feel insecure as they enter guest rooms to clean.

hospitality journal articlesFor one employee it was a naked man who fondled himself while she entered the room, another was attacked by dogs. If the guest complained management would often side with the guest and try to appease the guest with discounts or other amenities. This can significantly impact the working relationship between management and employees. In the face of these issues hospitality operators need to believe in their employees.

Energy Demands and Metabolic Equivalents (METS) in U-19 Basketball Refereeing During Official Games

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The metabolic demands among U-19 basketball players were studied; however, physical and physiological demands of U-19 basketball refereeing during competition are rather scant. The aim of this study was to analyze the energy expenditure (EE) and the exercise intensity of basketball refereeing during official game and determined as Metabolic Equivalent (METs). Sixteen elite level basketball referees were studied during U-19 basketball games (n=8) for time motion analyses (TMA).

sports medicine journal articlesThe EE data were calculated, using specific equations, from the time spent by the referee in each exercise-intensity zone. During game, referees spent a mean EE of 504.4 ± 77.7 kcal. A significant difference was observed between 113.5 ± 18.2 kcal in the 1st quarter (Q1) and 137 ± 27.5 kcal in the Q4 (p=0.007). The averaged EE (~5 kcal.kg-1.h-1) corresponded to “moderate energy intensity” (~5 METs) with a large contribution of the aerobic energy pathway.

Biological Behavior of MG63 Cells on the Hydroxyapatite Surface

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hydroxyapatite journal pdfThe response of human bone marrow cell to bone ash-derived hydroxyapatite (HA) and tuna bone derived HA powders was compared. HA ceramics were prepared from the commercial bone ash and waste of tuna bone. HA powders were prepared by soaking the bone ash and tuna bone in 0.1M of NaOH solution at 80 °C for 4 hours. Both powders were calcined at 800 °C for 1 hour to completely remove organic and were attritor-milled for 24 hours. The bone ash-derived HA (AHA) and tuna bone-derived HA (THA) ceramics were prepared by cold isostatically pressed and sintered 1200 °C with a dwell time of 1 hour. A human bone cell line MG-63 cells were used to test biocompatibility of AHA and THA ceramics. Cell suspensions in DMEM containing 10% FBS and 1% penicillin-streptomycin were seeded onto 24-well plate containing THA and AHA ceramics. Cell proliferation was evaluated by MTS assay, and cell morphology was observed by SEM.

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Stem Cells in Atrophic Acne Scars

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Acne is a distressing condition for physicians and patients alike. Over 90% adolescents acquire acne with 12-14% cases persisting even in adulthood. The condition and its’ sequelae may cause long term psychological disturbance to the patient as well as compromise in physical appearance.

journal granulationEtiologic factors such as increased sebum production, hormonal dysfunction, bacterial activity within the follicle (commonly Propionibacterium acnes) etc. are responsible for occurrence of acne. Acne healing process progresses through stages of follicular inflammation, granulation tissue formation and finally matrix remodelling. Scarring occurs due to skin damage during healing of active acne.

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Nationalization is a Direct Enemy to Entrepreneurship and it Kills Entrepreneurial Spirit: The Case of South Africa

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entrepreneurship journals impact factorThe debate about nationalisation was sparked by a resolution of the ANC Youth League’s 23rd National Congress in June 2008. Matshiqi posits that Kgalema Motlanthe ignited the debate way back in 2006 when he was invited to give a keynote address of the 62nd Anniversary Celebration of the ANC Youth League. Motlanthe challenged the ANC Youth League and the nation to debate on the idea of setting up of a mining company to fund free basic education and free higher education for all. Shivambu argues that the issue of nationalisation has always been ANC policy and was in line with the ANC’s Freedom Charter of 1955. He said that past ANC Presidents such as Oliver Tambo, Alfred Nzo and Nelson Mandela spoke about nationalization.

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