Microstratigraphic preservation of ancient faunal and hominin DNA in Pleistocene cave sediments

Ancient DNA recovered from Pleistocene sediments represents a rich resource for the study of past hominin and environmental diversity. However, little is known about how DNA is preserved in sediments and the extent to which it may be translocated between archaeological strata. Here, we investigate DNA preservation in 47 blocks of resin-impregnated archaeological sediment collected over the last four decades for micromorphological analyses at 13 prehistoric sites in Europe, Asia, Africa, and North America and show that such blocks can preserve DNA of hominins and other mammals. Extensive microsampling of sediment blocks from Denisova Cave in the Altai Mountains reveals that the taxonomic composition of mammalian DNA differs drastically at the millimeter-scale and that DNA is concentrated in small particles, especially in fragments of bone and feces (coprolites), suggesting that these are substantial sources of DNA in sediments. Three microsamples taken in close proximity in one of the blocks yielded Neanderthal DNA from at least two male individuals closely related to Denisova 5, a Neanderthal toe bone previously recovered from the same layer. Our work indicates that DNA can remain stably localized in sediments over time and provides a means of linking genetic information to the archaeological and ecological records on a microstratigraphic scale.

Autologous Tooth Dentin Graft: A Retrospective Study in Humans

Background and Objectives: The aim of this study is to evaluate the efficacy of an autologous dentin graft, via extracted teeth that are processed into bacteria-free particulate dentin in a Smart dentin grinder and then grafted immediately into alveolus post extraction or into bone deficiencies. Materials and Methods: Ten healthy, partially edentulous patients with some teeth in the mandible were recruited in the study. After their own teeth were grinded, particulate teeth were placed in empty sockets and bone defects after teeth extractions. Furthermore, after three, six, 12 and 24 months, core samples using a 3 mm trephine were obtained. Results: At three months, the particles of grinded tooth were immersed inside a new connective tissue with a small new bone formation (16.3 ± 1.98). At six months, we observed small particles of dentin integrated in new immature bone, without inflammation in the soft tissue (41.1 ± 0.76). At twelve months, we observed a high amount of bone formation surrounding tooth particles (54.5 ± 0.24), and at twenty-four months, new bone, a big structure of bone, was observed with dentin particles (59.4 ± 1.23), statistically different when compared it with at three months. Conclusions: A particulate dentin graft should be considered as an alternative material for sockets’ preservation, split technique, and also for sinus lifting. One of the special characteristics after 24 months of evaluation was the high resorption rate and bone replacement without inflammation. This material could be considered as an acceptable biomaterial for different bone defects due to its osteoinductive and osteoconductive properties

Readings in spatial patterns in space of “Bibi Fatima and the King’s sons” novel By Sheikh Dr. Sultan bin Mohammed Al Qasimi: قراءات في الأنماط المكانية في فضاء رواية: (بيبي فاطمة وأبناء الملك) للشيخ الدكتور سلطان بن محمد القاسمي

This research sought to read the spatial patterns in the novel of Bibi Fatima and the sons of the king, where I began the research by defining my theory of the term space, as a general concept that includes several spatial patterns that form its general structure. Thereafter I reviewed the features of the general space in the novel, to clarify the particles that constitute it, and I was able to monitor seven spatial patterns that define the features of this space, namely: (1) voluntary places of residence- (2) places of forced residence – (3) public places of movement- (4) private places of movement- (5) movable places (6) religious place and (7) the symbolism of the place. The aim of the study is to reveal the aesthetics of geographical space in the novel, as a narrative element that contributed with other narrative elements in construction of the novel. In this study, I adhered to the technical- analytical approach, which enabled me to monitor the small particles that resemble the space of the novel, and then classify and display these spatial particles according to the importance of its contribution to the formation and progress of the events of the novel. Perhaps the most important findings I have reached was the clear susceptibility shown by the text on technical analysis; Due to the diversity of spatial forms that resemble its geographical space. I recommend more research that deals with other elements of narration in the novel, such as separation of research about the structure of time, or about the status of the narrator and the nature of his correlations.

Polyphosphate affects cytoplasmic and chromosomal dynamics in nitrogen-starved Pseudomonas aeruginosa

Polyphosphate (polyP) synthesis is a ubiquitous stress and starvation response in bacteria. In diverse species, mutants unable to make polyP have a wide variety of physiological defects, but the mechanisms by which this simple polyanion exerts its effects remain unclear. One possibility is that polyP′s many functions stem from global effects on the biophysical properties of the cell. We characterize the effect of polyphosphate on cytoplasmic mobility under nitrogen-starvation conditions in the opportunistic pathogen Pseudomonas aeruginosa. Using fluorescence microscopy and particle tracking, we characterize the motion of chromosomal loci and free tracer particles in the cytoplasm. In the absence of polyP and upon starvation, we observe an increase in mobility both for chromosomal loci and for tracer particles. Tracer particles reveal that polyP also modulates the partitioning between a ′more mobile′ and a ′less mobile′ population: small particles in cells unable to make polyP are more likely to be ′mobile′ and explore more of the cytoplasm, particularly during starvation. We speculate that this larger freedom of motion may be a consequence of nucleoid decompaction, which we also observe in starved cells deficient in polyP. Our observations suggest that polyP limits cytoplasmic mobility and accessibility during nitrogen starvation, which may help to explain the pleiotropic phenotypes observed in the absence of polyP.

Microplastics: Small Particles, Big Threat

You have probably heard that plastic pollution is becoming a big problem for the environment, and especially for the oceans. When a piece of plastic reaches the sea, the seawater and sunlight make it slowly fall apart into tiny plastic particles. These small particles are called microplastics and are even smaller than a ladybug—and sometimes not even visible. Scientists have found that many marine animals mistake these microplastics for food and eat them! But what about the animals in coral reefs? Many animals in reefs, including corals and giant clams, are fixed to the bottom of the sea and cannot move. So, they cannot escape from the microplastics that are literally “raining down” on them. Recently, we discovered that many of these coral reef animals are not only eating the microplastics, but the plastics can also stick on their bodies like flies on flypaper!

Dining Lampblack Treatment Processes in China

The PM2.5 and other small particles produced by cooking oil fumes have contributed up to 25% to the urban atmospheric PM2.5, which has a bad impact on air quality and seriously threatens human health. Aiming at the pollution problem caused by catering oil fume, this article analyzes the threats of air pollution to human health based on the compositions and characteristics of catering oil fume, illustrates the development trend of China′s food and beverage lampblack control policy, and summarizes and points out the current situation and development trend of catering oil fume treatment. In order to provide ideas for the design of more efficient and energy-saving treatment processes in the future, the advantages and disadvantages were reviewed, and the improvement direction of the treatment technology was discussed.

Vertical Structure of a Snowfall Event Based on Observations From the Aircraft and Mountain Station in Beijing

An aircraft platform, ground-based disdrometer, cloud radar, radiometer, and automatic station were combined to study a snowfall case (16:30–21:00 observed by ground cloud radar) on the Yangqing Mountains in Beijing. Comparing the variation of ice habit and number concentration at aircraft altitude (2.9–3.2 km) and ground, we discussed the ice growth mechanisms in the Beijing Mountains. Results indicated that the snowfall was steady but not strong with reflectivity less than 20dBZ, and cloud top altitude less than 4.5 km. The number concentrations for both liquid and ice crystals at aircraft altitude and ground were very similar, both dominated by small particles at diameters of 0.1–1.2 mm, and the proportion of mean number concentrations at small diameters both in the aircraft and on the ground was large, peaking at 44 L−1 mm−1 and 8826 L−1 mm−1 respectively, and decreased rapidly as the diameter increased. There was no mixed phase in clouds with little liquid water. Particles were relatively regular, and were transparent with dendritic and disk-hexagonal shapes. The ice crystals and snowflakes were mainly grown by the deposition and aggregation, rarely by the riming process, and no secondary ice formation was observed.