Tissue Conditioner Incorporating a Nano-Sized Surface Pre-Reacted Glass-Ionomer (S-PRG) Filler

We aimed to evaluate the properties of a novel tissue conditioner containing a surface pre-reacted glass-ionomer (S-PRG) nanofiller. Tissue conditioners containing 0 (control), 2.5, 5, 10, 20, or 30 wt% S-PRG nanofiller or 10 or 20 wt% S-PRG microfiller were prepared. The S-PRG nanofillers and microfillers were observed using scanning electron microscopy. The ion release, acid buffering capacity, detail reproduction, consistency, Shore A0 hardness, surface roughness, and Candida albicans adhesion of the tissue conditioners were examined. The results indicated that the nanofiller particles were smaller and more homogeneous in size than the microfiller particles. In addition, Al, B, F, and Sr ions eluted from S-PRG were generally found to decrease after 1 day. Acid neutralization was confirmed in a concentration-dependent manner. The mechanical properties of tissue conditioners containing S-PRG nanofiller were clinically acceptable according to ISO standard 10139-1:2018, although the surface roughness increased with increasing filler content. Conditioners with 5–30 wt% nanofiller had a sublethal effect on C. albicans and reduced fungal adhesion in vitro. In summary, tissue conditioner containing at least 5 wt% S-PRG nanofiller can reduce C. albicans adhesion and has potential as an alternative soft lining material.

Analisis Pengaruh Kapasitas Penetralan Batugamping Dengan Menggunakan Metode Acid Buffering Characteristic Curve

Air Asam Tambang (AAT) merupakan sebuah permasalahan lingkungan sebagai salah satu akibat dari kegiatan penambangan yang mempunyai nilai pH dan kandungan logam terlarut yang relatif tinggi. Salah satu material yang dapat dimanfaatkan dalam mengatasi permasalahan AAT yaitu batugamping. Tujuan dari penelitian ini yaitu untuk mengetahui karakteristik penetralan batugamping dalam menetralkan asam dan untuk mengetahui pengaruh ukuran butir batugamping terhadap kapasitas penetralan. Penelitian dilakukan dengan metode pengujian Acid Buffering Characteristic Curve (ABCC). Hasil penelitian menunjukkan bahwa sampel batugamping berukuran 0,074 mm (100 mesh) mampu mempertahankan pH atau menunjukkan sifat buffer-nya pada rentang pH 5 setelah terjadi penambahan asam sebanyak 8,4 Kg H2SO4/t. Sementara sampel batugamping berukuran 0,149 mm (200 mesh) mampu mempertahankan nilai pH pada rentang pH 6 atau menunjukkan sifat buffer-nya setelah terjadi penambanahan asam sebanyak 1,2 Kg H2SO4/t. Kemudian semakin kecil ukuran butir batugamping maka semakin tinggi nilai pH yang dapat dipertahankan dan semakin besar ukuran butir batugamping maka semakin rendah nilai pH yang dapat dipertahankan.

Feasibility of Stabilized Zn and Pb Contaminated Soils as Roadway Subgrade Materials

The authors have developed a new binder, KMP, which is made from oxalic acid-activated phosphate rock, monopotassium phosphate (KH2PO4), and reactive magnesia (MgO). This study explores the acid neutralization capacity, strength characteristics, water-soaking durability, resilient modulus, and pore size distribution of KMP stabilized soils with individual Zn, Pb, or coexisting Zn and Pb contaminants. For comparison purpose, Portland cement (PC) is also tested. The results show that KMP stabilized soils have a higher acid buffering capacity than PC stabilized soils, regardless of the soil contamination conditions. The water stability coefficient and resilient modulus of the KMP stabilized soils are found to be higher than PC stabilized soils. The reasons for the differences in these properties between KMP and PC stabilized soils are interpreted based on the stability and dissolubility of the main hydration products of the KMP and PC stabilized soils, the soil pore distribution, and concentration of Mg or Ca leached from the KMP and PC stabilized soils obtained from the acid neutralization capacity tests. Overall, this study demonstrates that the KMP is effective in stabilizing soils that are contaminated with Zn or Pb alone and mixed Zn and Pb contaminants, and the KMP stabilized soils are better suited as roadway subgrade material.

Extreme diving in mammals: first estimates of behavioural aerobic dive limits in Cuvier's beaked whales

ABSTRACTWe analysed 3680 dives from 23 satellite-linked tags deployed on Cuvier's beaked whales to assess the relationship between long duration dives and inter-deep dive intervals and to estimate aerobic dive limit (ADL). The median duration of presumed foraging dives was 59 min and 5% of dives exceeded 77.7 min. We found no relationship between the longest 5% of dive durations and the following inter-deep dive interval nor any relationship with the ventilation period immediately prior to or following a long dive. We suggest that Cuvier's beaked whales have low metabolic rates, high oxygen storage capacities and a high acid-buffering capacity to deal with the by-products of both aerobic and anaerobic metabolism, which enables them to extend dive durations and exploit their bathypelagic foraging habitats.

New types of diaphragms and cervical caps versus older types of diaphragms and different gels for contraception: a systematic review

IntroductionOur primary objective was to evaluate whether new types of single-size diaphragms or cervical caps differ in prevention of pregnancy compared with older types of diaphragms, and whether different types of gels differ in their ability to prevent pregnancy. A secondary aim was to evaluate method discontinuation and complications.MethodsA comprehensive search was conducted in PubMed, Embase and the Cochrane Library. The certainty of evidence was assessed according to the GRADE system.ResultsFour randomised controlled studies were included in the assessment. When comparing the new and old types of female barrier contraceptives the 6-month pregnancy rate varied between 11%–15% and 8%–12%, respectively. More women reported inability to insert or remove the FemCap device (1.1%) compared with the Ortho All-Flex diaphragm (0%) (p<0.0306). Urinary tract infections were lower when using the single-size Caya, a difference of −6.4% (95% CI −8.9 to −4.09) compared with the Ortho All-Flex diaphragm. The 6-month pregnancy rate for acid-buffering gel and spermicidal nonoxynol-9 gel varied between 10% and 12%. The discontinuation rate was lower in women who used acid-buffering gel compared with nonoxynol-9 gel (risk ratio (RR) 0.77, 95% CI 0.68 to 0.97).ConclusionsPregnancy rates were generally high in women using female barrier contraceptives. There was no difference in the efficacy for pregnancy prevention between the new types of diaphragms and cervical caps and the older diaphragms. The new types of diaphragms and cervical caps resulted in fewer urinary tract infections. Acid-buffering gels did not differ from spermicidal nonoxynol-9 gels regarding pregnancies but seemed to be better tolerated.