The Kinematics of Proal Chewing in Rats.

Chewing kinematics are well-documented in several mammal species with fused mandibular symphyses, but relatively understudied in mammals with an unfused symphysis, despite the fact that more than half of extant Mammalia have an unfused mandibular symphysis. The Wistar brown rat () is widely used in human health research, including studies of mastication or neurological studies where mastication is the output behavior. These animals are known to have unfused mandibular symphyses and proal jaw (rostrocaudal) motion during occlusion, but the lack of high resolution, 3-dimensional analysis of rat chewing leaves the functional significance of symphyseal mobility unknown.

The Microbiological Drivers of Temporally Dynamic Dimethylsulfoniopropionate Cycling Processes in Australian Coastal Shelf Waters.

The organic sulfur compounds dimethylsulfoniopropionate (DMSP) and dimethyl sulfoxide (DMSO) play major roles in the marine microbial food web and have substantial climatic importance as sources and sinks of dimethyl sulfide (DMS). Seasonal shifts in the abundance and diversity of the phytoplankton and bacteria that cycle DMSP are likely to impact marine DMS (O) (P) concentrations, but the dynamic nature of these microbial interactions is still poorly resolved. Here, we examined the relationships between microbial community dynamics with DMS (O) (P) concentrations during a 2-year oceanographic time series conducted on the east Australian coast.

DMSP synthesis genes distinguish two types of DMSP producer phenotypes.

Dimethylsulfoniopropionate (DMSP) is an important organic carbon and sulfur source in the surface ocean that fuels microbial activity and significantly impacts Earth's climate. After three decades of research, the cellular role(s) of DMSP and environmental drivers of production remain enigmatic. Recent work suggests that cellular DMSP concentrations, and changes in these concentrations in response to environmental stressors, define two major groups of DMSP producers: high DMSP producers that contain ≥ 50 mM intracellular DMSP and low DMSP producers that contain < 50 mM.

The impact of COVID-19 on cervicofacial infection of dental aetiology.

Cervicofacial infections of dental aetiology can be life-threatening and with the closure of dental practices following the onset of the COVID-19, it would be anticipated that their prevalence presenting to maxillofacial surgery would increase and services may be overwhelmed, with patients presenting later with a potential subsequent increase in morbidity. A retrospective analysis of patients with cervicofacial infection of dental aetiology referred to maxillofacial surgery during the initial six weeks of COVID-19 lockdown in 2020 was carried out and compared with the equivalent period in the two preceding years. Unexpectedly, during COVID-19 lockdown, there was a reduction in patients seen with cervicofacial infection of dental aetiology.

Evidence for contrasting roles of dimethylsulfoniopropionate production in Emiliania huxleyi and Thalassiosira oceanica.

Dimethylsulfoniopropionate (DMSP) is a globally abundant marine metabolite and a significant source of organic carbon and sulfur for marine microbial ecosystems with the potential to influence climate regulation. However, the physiological function of DMSP has remained enigmatic for >30 yr. Recent insight suggests that there are different physiological roles for DMSP based on the cellular DMSP concentrations in producers.

The Trichodesmium consortium: conserved heterotrophic co-occurrence and genomic signatures of potential interactions.

The nitrogen (N)-fixing cyanobacterium Trichodesmium is globally distributed in warm, oligotrophic oceans, where it contributes a substantial proportion of new N and fuels primary production. These photoautotrophs form macroscopic colonies that serve as relatively nutrient-rich substrates that are colonized by many other organisms. The nature of these associations may modulate ocean N and carbon (C) cycling, and can offer insights into marine co-evolutionary mechanisms.

Prognostic factors in node-negative male breast cancer.

Background: Male breast cancer has traditionally been compared with female breast cancer, using the same staging system and prognostic indicators. A variety of histochemical and pathologic factors commonly used in node-negative female breast cancer were applied to 18 node-negative male breast cancers to assess their relevance to survival.

Patients And Methods: A slide review was performed for nuclear grade, lymphocytic infiltration, and lymphatic and vascular invasion.

Stability of preferences regarding life-sustaining treatment: a two-year prospective study of nursing home residents.

Background: The use of advance directives is based on the consensus that physicians should respect preferences expressed by competent patients about future treatments. Patient preferences are, however, subject to change and may be influenced by a number of factors. The purpose of our study was to evaluate the durability over time of decisions made regarding terminal care of mentally intact nursing home patients and the influence of such factors as intervening illness, loss of significant others, and cognitive, emotional and functional decline.