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Silver nanoplates (SNPs) are particularly attractive in surface-enhanced Raman scattering (SERS) activity due to their unique physicochemical properties, including localized surface plasmon resonance (LSPR) and strongly electromagnetic "hot spots" in the vicinity of their tips and edges. In this study, we report a novel, rapid, and simplified methodology for preparing SNPs using a one-pot synthesis approach with AgNO3, NaBH4, TSC, PVP, and an oxidation agent, H2O2. By adjusting precursor ratios, the LSPR peak can be easily adjusted from 400 to 800 nm, with a change in morphology from spherical, undefined structures, nano-disks, and triangular. In this study, Na2CO3 was added to the reaction to react with excess H2O2 to obtain long-term stable nanoparticles in a colloidal solution for 21 days. Crystal violet (CV) dye was used as a Raman probe to evaluate the SERS performance of SNP substrates at different diameters (35, 60, 120, 210 nm). The results showed that SERS activity was inverse to the SNP diameter. The finite-difference time domain (FDTD) was employed to compute the E-field around SNPs, indicating that E-field intensity depends on the SNPs' size, shape, and LSPR peak position. The 35 nm SNP substrates exhibited high sensitivity and good reproductivity in detecting CV dye, with a limit of detection (LOD) of 0.020 mg L−1 and a limit of quantification (LOQ) of 0.060 mg L−1. Additionally, SNP substrates can detect sulfathiazole (STZ) at trace-level concentrations, with LOD and LOQ of 0.031 and 0.095 mg L−1, respectively. These studies on silver nanoplate substrates displayed potential for further ultra-trace analysis applications in organic compounds. [ABSTRACT FROM AUTHOR]

Abstract: Cyanobacteria have long been thought to induce the formation of Ca‐carbonates as secondary by‐products of their metabolic activity, by shifting the chemical composition of their extracellular environment to conditions favoring mineral precipitation. Some cyanobacterial species forming Ca‐carbonates intracellularly were recently discovered. However, the environmental conditions under which this intracellular biomineralization process can occur and the impact of cyanobacterial species forming Ca‐carbonates intracellularly on extracellular carbonatogenesis are not known. Here, we show that these cyanobacteria can form Ca‐carbonates intracellularly while growing in extracellular solutions undersaturated with respect to all Ca‐carbonate phases, that is, conditions thermodynamically unfavorable to mineral precipitation. This shows that intracellular Ca‐carbonate biomineralization is an active process; that is, it costs energy provided by the cells. The cost of energy may be due to the active accumulation of Ca intracellularly. Moreover, unlike cyanobacterial strains that have been usually considered before by studies on Ca‐carbonate biomineralization, cyanobacteria forming intracellular carbonates may slow down or hamper extracellular carbonatogenesis, by decreasing the saturation index of their extracellular solution following the buffering of the concentration of extracellular calcium to low levels. [ABSTRACT FROM AUTHOR]

The regeneration and growth of commercially valuable tree species after selective logging are important for sustainable management of forest. This study compared density of seedlings (height < 2 m), saplings (height ≥ 2 m and diameter at breast height (dbh) < 10 cm) and trees (dbh ≥ 10 cm) of 18 commercially valuable tree species in Vietnam after 30 years of selective logging. Data were collected in high impact (where 30 to less than 50% standing volume was extracted), low impact (less than 30% standing volume was extracted) and unlogged forests. Results indicated that tree density in high impact forest was significantly higher than that in low impact and unlogged forests. Basal areas in high and low impact forests were significantly lower than that in unlogged forest. Density of ≥ 5 cm dbh saplings in high impact forest was significantly higher than that in low impact and unlogged forests. Seedling density in high impact forest was highest between the three forest stands. We concluded that a duration of 30 years was insufficient for logged forests to recover to the status of unlogged forest, regardless of logging intensities. [ABSTRACT FROM AUTHOR]

Some cyanobacteria, including Candidatus Gloeomargarita lithophora, which was isolated from Lake Alchichica (Mexico), can form intracellular carbonates. This contradicts the common paradigm that cyanobacterial calcification is always extracellular and suggests that calcification might be controlled by these cyanobacterial species. Intracellular carbonates have several peculiar characteristics: they are relatively small (between 60 and 500 nm), they are poorly crystalline, and they have Sr/Ca and Ba/Ca ratios much higher than the solution in which the cells grow. It is therefore crucial to understand whether these unique features may indicate the involvement of specific biological processes. Here, in vitro abiotic syntheses were performed to synthesize Mg-, Ca-, Sr- and Ba-containing carbonates with compositions, crystallinities and sizes close to those observed in intracellularly calcifying cyanobacteria. Precipitates were characterized by scanning and transmission electron microscopies coupled with energy dispersive X-ray spectroscopy, thermogravimetric analysis and X-ray diffraction. The size and the poor crystallinity of cyanobacterial intracellular carbonates could be mimicked under these abiotic conditions. It was shown that similarly to Mg, elements such as Sr and Ba can favor stabilization of poorly crystalline carbonates. In contrast, the differential partitioning of Sr, Ba and Ca between the solution and the solids as observed in cyanobacteria could not be mimicked in vitro . This provides keys to a better understanding of biological processes involved in the formation of intracellular carbonates by some cyanobacteria, including the involvement of membrane transporters. [ABSTRACT FROM AUTHOR]

Aim Neonatal deaths (≤28 days) account for more than half of child mortality in Vietnam. Presumably most die in hospital, but data are scarce. This study aimed to identify risk factors of death among hospitalised neonates. Methods We prospectively studied all neonatal deaths and expected deaths (discharged alive after withdrawal of life-sustaining treatment) in a Vietnamese tertiary paediatric hospital during a 12-month period in 2009-2010. The medical files were audited classifying admission prognosis, discharge outcome, cause of death/expected death according to two classifications, and important and potentially avoidable risk factors during the hospital stay. Results Among 5763 neonates admitted, 235 deaths and 67 expected deaths were included. According to both classifications, major causes were congenital malformations, prematurity and severe infections. Six risk factors were identified in 85% (60/71) of the neonates with a relatively good prognosis: recognition or response to danger signs, internal transfers, nosocomial infections, sepsis management, access to usual equipment/staff, and family perception. Conclusion Among 302 neonatal deaths/expected deaths, the major causes were congenital malformations, prematurity and severe infections. Six important and potentially avoidable risk factors could be addressed in the subgroup with relatively good admission prognosis, without implementing new technology or major organisational changes. [ABSTRACT FROM AUTHOR]

Two first class cricket bowlers presented with costoiliac pain secondary to rib impingement. In both patients, conservative management of the injury had failed to improve symptoms. Surgical resection of the affected rib was undertaken. At follow up, both patients had made a good recovery and had returned to competitive cricket. [ABSTRACT FROM AUTHOR]

Osteochondral lesions of the talus are well recognised clinical entities, however this report illustrates a rare case of an osteochondral defect in the distal fibula. A 15 year old male was referred to the orthopaedic services with a 9 month history of persistent ankle pain following an initial inversion injury. Plain X-ray was unremarkable but MRI and CT imaging revealed an osteochondral lesion at the level of the fibular physeal scar. The patient underwent an ankle arthroscopy where an unstable chondral flap was debrided and the associated fissure decompressed. The patient made an uneventful recovery and returned to normal sporting activities, symptom free. This diagnosis should be considered in patients presenting with chronic ankle pain particularly with a history of an inversion injury. The purpose of this report is to raise awareness of this condition. [ABSTRACT FROM AUTHOR]

Background: Mammary analogue secretory carcinoma (MASC) is a recently described pathologic entity. We report the case of a patient with an initial diagnosis of salivary acinic cell carcinoma later reclassified as MASC after next-generation sequencing revealed an ETV6-NTRK3 fusion. Patients and methods: This alteration was targeted with the pan-Trk inhibitor entrectinib (Ignyta), which possesses potent in vitro activity against cell lines containing various NTRK1/2/3 fusions. Results: A dramatic and durable response was achieved with entrectinib in this patient, followed by acquired resistance that correlated with the appearance of a novel NTRK3 G623R mutation. Structural modeling predicts that this alteration sterically interferes with drug binding, correlating to decreased sensitivity to drug inhibition observed in cell-based assays. Conclusions: This first report of clinical activity with TrkC inhibition and the development of acquired resistance in an NTRK3-rearranged cancer emphasize the utility of comprehensive molecular profiling and targeted therapy for rare malignancies (NCT02097810). [ABSTRACT FROM AUTHOR]

Tricuspid valve perforation with pacemaker lead is one of the extremely rare complications of transvenous pacemaker implantation. Approximately all reported cases have been diagnosed at autopsy. The authors present a case of tricuspid valve perforation caused by pacemaker lead that was diagnosed during cardiac surgery and treated successfully by removing the lead and suturing the tricuspid valve. [ABSTRACT FROM AUTHOR]

Undergraduate medical training aims to provide doctors with a solid foundation, which will enable them to embark on a broad range of career pathways. Within this skill set, doctors should feel confident in basic first aid principles and man agement of core trauma injuries. With junior doctors participating in sport, as spectators or even as event medics, these skills may readily be required. We therefore undertook this study to explore any deficiencies in the current curriculum. 199 senior student doctors in a UK medical school completed a questionnaire to evaluate their clinical trauma skills. Only a small proportion (8%) had previous first aid experience within the St. Johns ambulance. Over three quarters of students (78%) felt unable to apply a broad arm sling, only a quarter (26%) felt competent to apply a collar and cuff and less than half (44%) stating they were able to neighbour strap fingers. 35% of students admitted to lacking confidence in log rolling a patient and only 36% of students stated they understood the principles of 'clearing a C Spine'. Similar inexperience in the hospital management of ankle injuries was exposed with most (75%) un-aware of the Ottawa ankle rules. This study demonstrates many students lack the knowledge and confidence in performing basic first aid procedures. It also highlights a possible deficiency in trauma training and supports the need to strengthen the practical application of medical undergraduate education in these areas. [ABSTRACT FROM AUTHOR]