Band gap engineering in simultaneous phononic and photonic crystal slabs

We discuss the simultaneous existence of phononic and photonic band gaps in two types of phononic crystals slabs, namely periodic arrays of nanoholes in a Si membrane and of Si nanodots on a SiO2 membrane. In the former geometry, we investigate in detail both the boron nitride lattice and the square lattice with two atoms per unit cell (these include the square, triangular and honeycomb lattices as particular cases). In the latter geometry, some preliminary results are reported for a square lattice

A SIMPLE WAY TO MEASURE THE DYNAMIC VISCOSITY OF A FLUID

In this paper, we measured the viscosity of different fluids, including edible oils and soaps, at a constant temperature, using two experimental methods. Namely, the falling ball and the oscillation of the mass-spring system inside a fluid. Three different masses were used to evaluate the viscosity obtained by the falling ball method. The results were very similar. More precision of the viscosity value is done using a calibration curve. The results are compared with those measured by the mass-spring system and they show good agreement. This simple way of viscosity measurement using mechanical physics concepts can be used for educational purposes such as the practical work of a bachelor

PELATIHAN PEMBUATAN VCO DALAM MENUNJANG PROJEK PENGUATAN PROFIL PELAJAR PANCASILA (P5) DI SMA ST. PAULUS WELIMAN

Telah dilakukan pengabdian kepada Masyarakat di SMA St. Paulus Weliman Kabupaten Malaka tentang pembuatan Virgin Coconut Oil (VCO) sebagai proyek kewirausahaan dalam menunjang Proyek Penguatan Profil Pelajar Pancasila (P5). Kegiatan ini meliputi siswa-siswi kelas 10 SMA ST. Paulus Weliman yang berjumlah 26 orang, 1 guru mata Pelajaran dan 2 orang tim pengabadian dari program studi kimia universitas timor yang terdiri dari 1 dosen dan 1 mahasiswa. Pengabdian ini dilaksanakan selama 2 hari. Tujuan dari pengabdian ini untuk melatih siswa-siswi kelas X untuk menciptakan VCO yang berkualitas untuk dijadikan produk unggulan dalam proyek kewirausahaan. Metode yang digunakan dalam pengabdian ini berupa diskusi dan eksperimen. Pada metode diskusi tim pengabdian menjelaskan materi yang berkaitan dengan VCO seperti proses pembuatan sampai dengan manfaat VCO bagi kesehatan. VCO yang dihasilkan dikemas untuk diperjual-belikan. Keberhasilan pelatihannya dilihat berdasarkan hasil kusioner yang dibagikan

PENGARUH PERBANDINGAN RUMPUT ODOT DAN ISI RUMEN SAPI PADA SILASE PAKAN KOMPLIT TERHADAP KANDUNGAN PROTEIN KASAR, KANDUNGAN SERAT KASAR, DAN KONSENTRASI VFA, SERTA NH3 IN-VITRO

Penelitian ini bertujuan untuk mengetahui pengaruh perbandingan rumput odot dan isi rumen sapi dalam pembuatan silase pakan komplit terhadap kandungan protein kasar, kandungan serat kasar, konsentrasi asam lemak terbang (VFA) serta NH3 in vitro. Metode yang digunakan adalah metode eksperimental dengan menggunakan rancangan acak lengkap (RAL) terdiri dari 4 perlakuan dan 4 ulangan. Perlakuan yang diterapkan adalah P0 = rumput odot 70% + konsentrat 30%, P1 = rumput odot 60% + isi rumen sapi 10% + konsentrat 30%, P2 = rumput odot 50% + isi rumen sapi 20% + konsentrat 30%, P3 = rumput odot 40% + isi rumen sapi 30% + konsentrat 30% . Data dianalisis menggunakan Analysis of variance (ANOVA) dan dilanjutkan dengan uji jarak berganda Duncan. Hasil penelitian ini menunjukkan bahwa perlakuan berpengaruh sangat nyata (P<0,01) terhadap kandungan protein kasar, serat kasar dan konsentrasi VFA tetapi tidak berpengaruh nyata (P>0,05) terhadap konsentrasi NH3. Disimpulkan bahwa meningkatnya persentase isi rumen sapi dan menurunnya rumput odot pada pembuatan silase pakan komplit mengakibatkan terjadinya penurunan kandungan PK, dan peningkatan kandungan SK sedangkan konsentrasi VFA mengalami penurunan dan tidak terdapat perbedaan konsentrasi NH3 dengan perlakuan kontrol. Kata kunci: isi rumen sapi, rumput odot, perbandingan silase pakan komplit, in vitro

Food Safety Assessment and Nutraceutical Outcomes of Dairy By-Products: Ovine Milk Whey as Wound Repair Enhancer on Injured Human Primary Gingival Fibroblasts

The valorization of milk whey appears to be a promising strategy for managing by-products from dairy food industries, which incur demanding economic costs for treatment and/or disposal. Thanks to its numerous bioactive components, whey is expected to be increasingly incorporated into foods in the future. We investigated the safety of ovine milk whey through in vitro experiments on human primary gingival fibroblast (HGF-1) proliferation and wound healing. Fibroblasts play a crucial role in the repair processes from the late inflammatory phase until the final stages. Cells treated with varying concentrations of ovine whey (0.01%, 0.1%, 1%, and 10%) were able to close wounds more rapidly than vehicle-treated cells. Time- and dose-dependent responses were observed in cell populations exposed to ovine whey. Specifically, wounds treated with 0.1% and 10% milk whey showed better migratory capabilities compared to those treated with 0.01% and 1% milk whey after 24 and 48 h. In addition, ovine milk whey stimulates extracellular matrix deposition, as evidenced by the increasing levels of CD44 antigen density evaluated through FACS analysis, as well as COL1A1 expression measured both via RT-qPCR and immunofluorescence. This phenomenon was particularly evident at concentrations of 0.01% and 10%. Ensuring quality and safety has become a major concern for health authorities in the food industry. Our findings suggest that ovine milk whey is safe and possesses regenerative properties. It facilitates tissue re-establishment following exposure to environmental stress, particularly accelerating gingival wound closure

Whole-body tissue stabilization and selective extractions via tissue-hydrogel hybrids for high-resolution intact circuit mapping and phenotyping

To facilitate fine-scale phenotyping of whole specimens, we describe here a set of tissue fixation-embedding, detergent-clearing and staining protocols that can be used to transform excised organs and whole organisms into optically transparent samples within 1–2 weeks without compromising their cellular architecture or endogenous fluorescence. PACT (passive CLARITY technique) and PARS (perfusion-assisted agent release in situ) use tissue-hydrogel hybrids to stabilize tissue biomolecules during selective lipid extraction, resulting in enhanced clearing efficiency and sample integrity. Furthermore, the macromolecule permeability of PACT- and PARS-processed tissue hybrids supports the diffusion of immunolabels throughout intact tissue, whereas RIMS (refractive index matching solution) grants high-resolution imaging at depth by further reducing light scattering in cleared and uncleared samples alike. These methods are adaptable to difficult-to-image tissues, such as bone (PACT-deCAL), and to magnified single-cell visualization (ePACT). Together, these protocols and solutions enable phenotyping of subcellular components and tracing cellular connectivity in intact biological networks

Utilization of Dairy By-Products as a Source of Functional and Health Compounds—The Role of Ovine Colostrum and Milk Whey on Chronic Myeloid Leukemia Cells

Nowadays, the search for food products that promote consumers’ health has gained interest, and dairy by-products, due to their biological quality, could have a prominent position among products with health benefits. However, little is known about their activity on cancer cells. This study aimed to provide evidence about the effect of ovine colostrum and milk whey on K562 cells, a model of the human chronic myeloid leukemia cell line. The exposure of K562 cells to a single administration of sheep by-products at different concentrations for three days and three treatments for three days was carried out. Using a flow cytometric approach, we found that CD235a expression remained stable in the cells exposed to ovine whey (milk and colostrum) at concentrations ranging from 1 ng/mL to 100 μg/mL, after three days from one or three administrations, respectively. A significant reduction in fluorescent cells was observed in the populations exposed to 1 mg/mL of both milk and colostrum at the same time points. In these conditions, the size and granularity of the leukemic cells also changed, with a substantial reduction in the number of actively dividing cells in the S phase of the cell cycle. This phenomenon was highlighted by the Annexin V/PI cytofluorimetric test, which is able to provide quantitative results regarding the population of cells in early or late apoptosis or necrotic cells after exposure to a single dose or three doses of colostrum or sheep whey for three days, respectively. This report showed that both colostrum and milk whey were able to modify the phenotypic profile and cell cycle of the K562 cell line, inducing apoptosis at the highest concentration

Tribological and Wear Properties of Multi-Layered Materials

The usage of fabrics as reinforcements in composites is spreading due to fabrics’ properties. The use of fabrics allows obtaining of sinuous surfaces, for instance, unlike the use of prepregs. Using fabrics as reinforcements it is also possible to obtain laminate-like materials having the same matrix in all their volume. In the case of pre-pregs usage always it is necessary to discuss about the bonding between individual plies. For this study eight materials were formed. The forming method consisted in placing the pre-polymer imbued fabric pieces into a mould to obtain plates of composites. Two types of fabric were used: one simple type of untwisted tows of carbon fibres and the second one simple type of alternated untwisted tows of carbon and aramide fibres. Both fabrics were prepared in order to ensure the matrix adherence. The polymer matrix is realised from epoxy system EPIPHEN RE 4020 / EPIPHEN DE 4020 filled with clay and talc in equal amounts of 5% (weight ratio). The use of clay and talc were meant to improve the thermal dimensional stability of final materials. Tribological properties of formed materials were studied using pin-on-disk method with steel disk and pins made of materials. Both orientation of reinforcement fibres relative to friction direction were taken into account. Results are encouraging further studies in order to identify the best solution of forming a multi-component material with more than one designable property