Taxonomic and functional diversity of benthic macrofauna associated with rhodolith beds in SE Brazil

Rhodoliths are free-living and morphologically diverse marine calcareous algae commonly distributed over the continental shelf seafloor. They increase the seabed structural complexity and are of potential value as feeding and reproductive grounds for a myriad of marine fauna. The higher structural seabed complexity within rhodolith beds may also increase benthic diversity by creating microhabitats, but this relationship has been rarely explored within rhodolith beds worldwide. Here we compared benthic macrofaunal (>500 µm) structure on rhodolith beds (nodule epifauna) and within unconsolidated sediments (sediment infauna) under high and low-density beds to test whether rhodolith bed density and nodule morphology influenced macrofaunal assemblages. We observed that macrofaunal density on nodules (2538 ± 288.7 ind·m−2) was 15-fold higher when compared to sediments under those beds (166 ± 38.8 ind·m−2). Rhodolith bed density was positively related to macrofaunal density, composition, and functional diversity on the rhodoliths. Low-density beds (61 ± 27.1 nodules·m−2) with discoid-shape nodules were dominated by peracarid crustaceans whereas high-density beds (204 ± 18.7 nodules·m−2) with spheroidal nodules were dominated by Annelid polychaetes. The sediment macrofauna was also positively influenced by the density of rhodolith nodules, which increased sediment carbonate and organic quality (protein and lipids) under high-density beds. Macrofaunal functional diversity was generally higher on rhodoliths, with low similarity (low nestedness) and high taxa turnover between macrofaunal assemblages of rhodoliths and sediments. These findings indicate that rhodolith beds provide an unique habitat for benthic macrofaunal communities, with exclusive functional and taxonomic richness that are likely not typical in the unconsolidated sediment below these beds in SE Brazil. This study highlights the importance of protecting rhodolith beds from multiple sources of anthropogenic disturbance and exploration on continental shelves.

A Comparison of Laboratory Simulation Methods of Iron Contamination for FCC Catalysts

Two different methods of simulating iron contamination in a laboratory were studied. The catalysts were characterized using X-ray diffraction, N2 adsorption–desorption, and SEM-EDS. The catalyst performance was evaluated using an advanced cracking evaluation device. It was found that iron was evenly distributed in the catalyst prepared using the Mitchell impregnation method and no obvious iron nodules were found on the surface of the catalyst. Iron on the impregnated catalyst led to a strong dehydrogenation capacity and a slight decrease in the conversion and bottoms selectivity. The studies also showed that iron was mainly in the range of 1–5 μm from the edge of the catalyst prepared using the cycle deactivation method. Iron nodules could be easily observed on the surface of the catalyst. The retention of the surface structure in the alumina-rich areas and the collapse of the surface structure in the silica-rich areas resulted in a continuous nodule morphology, which was similar to the highly iron-contaminated equilibrium catalyst. Iron nodules on the cyclic-deactivated catalyst led to a significant decrease in conversion, an extremely high bottoms yield, and a small increase in the dehydrogenation capacity. The nodules and distribution of iron on the equilibrium catalyst could be better simulated by using the cyclic deactivation method.

A new species of Crocodile Newt Tylototriton (Caudata: Salamandridae) from Shan State, Myanmar (Burma)

A phylogenetic taxonomic analysis of a monophyletic subgroup of the salamandrid genus Tylototriton revealed that a newly discovered population from Ngar Su Village, 1 km south of Ywangan, Shan State, Myanmar is a new species and most closely related to T. shanorum from approximately 80 km to the west in the vicinity of Taunggyi, Shan State. Tylototriton ngarsuensis sp. nov. differs from other closely related species of Tylototriton on basis of varying combinations of characteristics associated with it shorter head, larger size, rib nodule morphology, and overall drab, very dark, coloration, along with its genetic differentiation. Tylototriton ngarsuensis sp. nov. also appears to breed later in the year than most other species. Unfortunately, this species like many other Asian newts, is being harvested for the pet and medicinal trade and given its restricted distribution, this could pose a serious threat to its long-term survival.

Nodule-in-Nodule Imaging Pattern in Hepatocellular Carcinoma Treated by Transarterial Chemoembolization – a Multiparametric Magnetic Resonance Imaging Study

Background & Aims: Emerging minimally invasive treatments for hepatocellular carcinoma (HCC) can significantly improve a patient’s prognosis, but they may alter the imaging features of the treated nodules. This study focuses on a series of patients presenting with a rare pathology, the nodule-in-nodule imaging pattern of HCC, analyzes the imaging features and discusses possible approaches for the diagnosis of tumoral recurrence.Method: Nine patients recruited over two years, having HCC with nodule-in-nodule imaging pattern on diagnosis, and treated by transarterial chemoembolization were monitored by magnetic resonance imaging (MRI). Nodule morphology, dynamic contrast behavior and size progression were followed in this study.Results: All patients showed tumor recurrence. In 7 nodules, a T2 weighted-imaging hyperintense signal of the HCC foci was found, with isointensity of the background nodule. Restricted diffusion within the HCC foci was found in 6 cases but with no statistical significance. Dynamic contrast images evaluation showed a “classical” enhancement pattern in five patients. All nodules had hypointense HCC foci in the hepatobiliary phase. Four patients demonstrated progressive disease according to the mRECIST criteria.Conclusions: Due to the particularly challenging nodule characteristics, the sensitivity in diagnosing HCC foci in these nodules is about 77% when using conventional imaging criteria related to nodule morphology. Contrast media uptake curves may be altered by changes in nodule hemodynamics caused by embolization. The diagnostic rate may be significantly increased by considering the tumoral size increase in follow-up studies and completing the study with a hepatobiliary phase using Acidum Gadoxeticum.Abbreviations. ADC: Apparent diffusion coefficient; CT: Computed tomography; DEB-TACE: drug-eluting beads transarterial chemoembolization; DWI: Diffusion-weighted imaging; Gd-EOB-DTPA: acidum gadoxeticum; HCC: hepatocellular carcinoma; HBV: hepatitis virus B; HCV: hepatitis virus C; HDV: hepatitis virus D; IN-OPP: in-phase and out-of-phase; mRECIST: modified Response Evaluation Criteria in Solid Tumors; MRI: Magnetic resonance imaging; ROI: region of interest; TACE: Transarterial chemoembolization; WI: weighted imaging.