Electrical discharge machining of polycrystalline diamond using copper electrode – finishing condition

Research on machining process of Polycrystalline Diamond (PCD) is becoming important as the material was believed suitable to be used for cutting tools of advanced aeronautical structure. Electrical Discharge Machining (EDM) was regarded as the suitable method to machine PCD due its noncontact process nature. The objective of this research is to determine the influence of several EDM parameter such as sparking current, pulse duration, and pulse interval to the material removal rate and surface roughness of the machined PCD. Instead of significantly influenced the material removal rate, the sparking current was also highly influenced tha surface roughness. Highest material removal rate of approximately 0.005mm3/s was recorded by the EDM process with the highest current used of 5A, and lowest pulse interval of 1µs. The influence of pulse duration is not clearly seen at the lowest pulse interval used. On the other hand, 0.4µm was the lowest surface roughness value obtained in this research indicated by the highest sparking current, highest sparking duration and lowest sparking interval of 5A, 1µs and 1µs respectively

Novice teachers\u27 experiences of community service-learning

This study focuses on beginning teachers\u27 experiences with a currently popular curriculum strategy in the US: community service-learning. To determine the personal and contextual factors influencing novice teachers\u27 experiences, we surveyed over 300 early career teachers and interviewed 30 of the larger sample. The study provides evidence that some beginning teachers are willing to implement strategies they learned in their teacher education programs, and can do so successfully, in spite of being busy and unsupported. Results indicate that specific preparation features and school characteristics may play a large role in whether novice teachers implement service-learning activities in their classrooms

Effects of Drug Physicochemical Properties on In-Situ Forming Implant Polymer Degradation and Drug Release Kinetics

In-situ forming implants (ISFIs) represent a simple, tunable, and biodegradable polymer-based platform for long-acting drug delivery. However, drugs with different physicochemical properties and physical states in the polymer-solvent system exhibit different drug release kinetics. Although a few limited studies have been performed attempting to elucidate these effects, a large, systematic study has not been performed until now. The purpose of this study was to characterize the in vitro drug release of 12 different small molecule drugs with differing logP and pKa values from ISFIs. Drug release was compared with polymer degradation as measured by lactic acid (LA) release and change in poly(DL-lactide-co-glycolide) (PLGA) molecular weight (MW) measured by size exclusion chromatography with multi-angle laser light scattering (SEC-MALS). Drug physical state and morphology were also measured using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Together, these results demonstrated that hydrophilic drugs have higher burst release at 24 h (22.8–68.4%) and complete drug release within 60 days, while hydrophobic drugs have lower burst release at 24 h (1.8–18.9%) and can sustain drug release over 60–285 days. Overall, drug logP and drug physical state in the polymer–solvent system are the most important factors when predicting the drug release rate in an ISFI for small-molecule drugs. Hydrophilic drugs exhibit high initial burst and less sustained release due to their miscibility with the aqueous phase, while hydrophobic drugs have lower initial burst and more sustained release due to their affinity for the hydrophobic PLGA. Additionally, while hydrophilic drugs seem to accelerate the degradation of PLGA, hydrophobic drugs on the other hand seem to slow down the PLGA degradation process compared with placebo ISFIs. Furthermore, drugs that were in a crystalline state within the ISFI drugs exhibited more sustained release compared with amorphous drugs

Effects of Injection Volume and Route of Administration on Dolutegravir In Situ Forming Implant Pharmacokinetics

Due to the versatility of the in situ forming implant (ISFI) drug delivery system, it is crucial to understand the effects of formulation parameters for clinical translation. We utilized ultrasound imaging and pharmacokinetics (PK) in mice to understand the impact of administration route, injection volume, and drug loading on ISFI formation, degradation, and drug release in mice. Placebo ISFIs injected subcutaneously (SQ) with smaller volumes (40 μL) exhibited complete degradation within 30–45 days, compared to larger volumes (80 μL), which completely degraded within 45–60 days. However, all dolutegravir (DTG)-loaded ISFIs along the range of injection volumes tested (20–80 μL) were present at 90 days post-injection, suggesting that DTG can prolong ISFI degradation. Ultrasound imaging showed that intramuscular (IM) ISFIs flattened rapidly post administration compared to SQ, which coincides with the earlier Tmax for drug-loaded IM ISFIs. All mice exhibited DTG plasma concentrations above four times the protein-adjusted 90% inhibitory concentration (PA-IC90) throughout the entire 90 days of the study. ISFI release kinetics best fit to zero order or diffusion-controlled models. When total administered dose was held constant, there was no statistical difference in drug exposure regardless of the route of administration or number of injections

Clinicopathological parameters, recurrence, locoregional and distant metastasis in 115 T1-T2 oral squamous cell carcinoma patients

The incidence of oral squamous cell carcinoma remains high. Oral and oro-pharyngeal carcinomas are the sixth most common cancer in the world. Several clinicopathological parameters have been implicated in prognosis, recurrence and survival, following oral squamous cell carcinoma. In this retrospective analysis, clinicopathological parameters of 115 T1/T2 OSCC were studied and compared to recurrence and death from tumour-related causes. The study protocol was approved by the Joint UCL/UCLH committees of the ethics for human research. The patients' data was entered onto proformas, which were validated and checked by interval sampling. The fields included a range of clinical, operative and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death and last clinic review. Causes of death were collated in 4 categories (1) death from locoregional spread, (2) death from distant metastasis, (3) death from bronchopulmonary pneumonia, and (4) death from any non-tumour event that lead to cardiorespiratory failure. The patients' population comprised 65 males and 50 females. Their mean age at the 1 diagnosis of OSCC was 61.7 years. Two-thirds of the patients were Caucasians. Primary sites were mainly identified in the tongue, floor of mouth (FOM), buccal mucosa and alveolus. Most of the identified OSCCs were low-risk (T1N0 and T2N0). All patients underwent primary resection neck dissection and reconstruction when necessary. Twenty-two patients needed adjuvant radiotherapy. Pathological analysis revealed that half of the patients had moderately differentiated OSCC. pTNM slightly differed from the cTNM and showed that 70.4% of the patients had low-risk OSCC. Tumour clearance was ultimately achieved in 107 patients. Follow-up resulted in a 3-year survival of 74.8% and a 5-year survival of 72.2%. Recurrence was identified in 23 males and 20 females. The mean age of 1 diagnosis of the recurrence group was 59.53 years. Most common oral sites included the lateral border of tongue and floor of mouth. Recurrence was associated with clinical N-stage disease. The surgical margins in this group was evaluated and found that 17 had non-cohesive invasion, 30 had dysplasia at margin, 21 had vascular invasion, 9 had nerve invasion and 3 had bony invasion. Severe dysplasia was present in 37 patients. Tumour clearance was achieved in only 8 patients. The mean depth of tumour invasion in the recurrence group was 7.6 mm. An interesting finding was that 5/11 patients who died of distant metastasis had their primary disease in the tongue. Nodal disease comparison showed that 8/10 patients who died of locoregional metastasis and 8/11 patients who died from distant metastasis had clinical nodal involvement. Comparing this to pathological nodal disease (pTNM) showed that 10/10 patients and 10/11 patients who died from locoregional and distant metastasis, respectively, had nodal disease. All patients who died from locoregional and distant metastasis were shown to have recurrence after the primary tumour resection. Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the cervical lymph nodes. Several clinicopathological parameters can be employed to assess outcome, recurrence and overall survival. © 2010 Jerjes et al; licensee BioMed Central Ltd

The Importance of Using Computer Technologies in the Organization of Chemistry Education

This article provides information on the use and importance of computer technology in the development of cognitive research in the teaching process of chemistry in general secondary schools

Penerapan Konsep Edutainment (Bernyanyi) dalam Pembelajaran Mengenal Abjad di Kelompok A di Paud Tuan Guru Alim Kota Ternate

Peneliti ini dilakukkan dengan tujuan untuk Penerapan Konsep Edutainment (Bernyanyi) Dalam Pembelajaran Mengenal Abjad Pada Kelompok A Usia Dini 4-5 Tahun di PAUD Tuan Guru Alim Kota Ternate 2019/2020. Subjekif yang dipakai dalam penelitian ini adalahguru, gurudan anak. Metode penelitian yang digunakan dalam penelitian ini adalah metode kualitatif deskritif dengan menggunakan teknik pengumpulan data berupa obsevasi, wawancara dan dokumentasi. Adapun teknik analisis data yang digunakan dalam penelitian ini yaitu contet analyisis dari Miles dan Huberman. Hasil yang diperoleh dari penelitian ini menyatakan bahwa dalam menggunakan poster huruf dalam pembelajaran mengenal abjad pada kelompok A mulai berkembang baik dalam indikator huruf besar dan huruf kecil yang mendapat kriteria bintang (***) BSH 5 anak, bintang (**) MB 3 anak, dan bintang (*) BB 1 anak,bintang (****) BSB 1 anak dan dapat menunjuk huruf dengan benar dan cepat yang mendapatkan kriteria bintang (***) BSH 5 anak, bintang (**) MB 3 anak, bintang (****) BSB 1 anak dan bintang(*) BB 1 anak. Menyebutkan dan membedakan huruf besar dan huruf kecil MB 3 anak, BSH 5 anak BSB 1 anak, BB 1 anak. Menunjuk huruf dengan benar dan cepat menggunakan media poster huruf A-Z, BB 1 anak, MB 3 anak, BSH 5 anak, BSB 1 anak, sehingga poster huruf membuat anak cepat mengenal dengan baik, tujuannya untuk mempermudahkan anak mengenal abjad dan dapat stimulasi bagi anak

The Efficacy of Alternative Therapies for Children and Adolescents with Depression and Anxiety

Depression and anxiety in children and adolescents are rising worldwide, yet conventional treatments such as psychotherapy and medication often face challenges of limited effectiveness, accessibility, and acceptability. Here, we review evidence on alternative therapies, including creative arts, physical activity, mind-body practices such as yoga and mindfulness, animal- assisted interventions, and biologically based approaches. Across outcomes, the strongest evidence supports creative therapies, play therapy, and structured physical activity, which consistently reduce depression and anxiety and may enhance psychosocial functioning. Evidence for mindfulness, animal-assisted therapy, light therapy, and aromatherapy is more modest, while supplements and other biologically based remedies remain inconclusive. Collectively, these approaches show potential to reduce stress, broaden engagement, and address barriers such as stigma when integrated alongside standard care. Future priorities include larger, well-controlled trials, attention to long-term outcomes, and culturally sensitive evaluation to guide safe, personalized implementation