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Oxalate-rich mineral accretions, often found in rock shelters around the world, offer important opportunities for radiocarbon dating of associated rock art. Here, sample characterization and chemical pretreatment techniques are used to characterize the accretions, prescreen for evidence of open-system behavior, and address potential contamination. The results provide stratigraphically consistent sequences of radiocarbon dates in millimeter-scale laminated accretions, demonstrating their reliability for dating rock art, particularly symbolic markings commonly engraved into these relatively soft deposits. The age sequences are also consistent with correlations between distinctive patterns in the layer sequences visible in shelters up to 90 km apart in the Kimberley region of northwestern Australia, suggesting their synchronized formation is not entirely shelter specific but broadly controlled by variations in regional environmental conditions. Consequently, these accretions also offer potential as paleoenvironmental archives, with radiocarbon dating of layers in nine accretions indicating four, approximately synchronous growth intervals covering the past 43 ka., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Naturalistic depictions of animals are a common subject for the world's oldest dated rock art, including wild bovids in Indonesia and lions in France's Chauvet Cave. The oldest known Australian Aboriginal figurative rock paintings also commonly depict naturalistic animals but, until now, quantitative dating was lacking. Here, we present 27 radiocarbon dates on mud wasp nests that constrain the ages of 16 motifs from this earliest known phase of rock painting in the Australian Kimberley region. These initial results suggest that paintings in this style proliferated between 17,000 and 13,000 years ago. Notably, one painting of a kangaroo is securely dated to between 17,500 and 17,100 years on the basis of the ages of three overlying and three underlying wasp nests. This is the oldest radiometrically dated in situ rock painting so far reported in Australia.

Understanding how sediment transport and storage will delay, attenuate, and even erase the erosional signal of tectonic and climatic forcings has bearing on our ability to read and interpret the geologic record effectively. Here, we estimate sediment transit times in Australia's largest river system, the Murray-Darling basin, by measuring downstream changes in cosmogenic 26 Al/ 10 Be/ 14 C ratios in modern river sediment. Results show that the sediments have experienced multiple episodes of burial and reexposure, with cumulative lag times exceeding 1 Ma in the downstream reaches of the Murray and Darling rivers. Combined with low sediment supply rates and old sediment blanketing the landscape, we posit that sediment recycling in the Murray-Darling is an important and ongoing process that will substantially delay and alter signals of external environmental forcing transmitted from the sediment's hinterland., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

The Kimberley region in Western Australia hosts one of the world's most substantial bodies of indigenous rock art thought to extend in a series of stylistic or iconographic phases from the present day back into the Pleistocene. As with other rock art worldwide, the older styles have proven notoriously difficult to date quantitatively, requiring new scientific approaches. Here, we present the radiocarbon ages of 24 mud wasp nests that were either over or under pigment from 21 anthropomorphic motifs of the Gwion style (previously referred to as "Bradshaws") from the middle of the relative stylistic sequence. We demonstrate that while one date suggests a minimum age of c. 17 ka for one motif, most of the dates support a hypothesis that these Gwion paintings were produced in a relatively narrow period around 12,000 years ago., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Two major theories on renal stone formation will be reviewed, the "free-particle" and "fixed-particle" mechanisms. These theories combine data on intrinsic factors (inborn metabolic errors), extrinsic factors (diet), renal cell responses and the physico-chemistry and biochemistry of urine into mechanisms of stone formation. This paper describes the specific role of time in both mechanisms. The timeline of crystal- and stone formation was deducted from literature data and was measured for two stones using radioisotope decay analysis. The stones of similar size and composition showed, respectively, a timeline of a few years and a development that took decades. In combination with data on stone architecture and patient characteristics these timelines are explained using the free-particle and fixed-particle mechanisms. Consideration of the timeline of stone formation has clinical implications. We conclude that the fixed-particle mechanism can be a slow process where decades pass between the first formation of a precipitate in the renal interstitium and the clinical presentation of the stone. Added to the fact that the mechanism of this initial precipitation is still ill defined, the conditions that started fixed-particle stone formation in an individual patient can be obscure. Blood and urine analysis in such patients does not necessarily reveal the individual's risk for recurrence as lifestyle may have changed over time. This is in fact what defines the so-called idiopathic stoneformers. For these patients, prevention of outgrowth of previously formed precipitates, papillary plaques, may be more relevant than prevention of new plaque formation. In contrast, a patient who has formed a stone in a relatively short time through the free-particle mechanism is more likely to show abnormal values in blood and urine that explain the starting event of stone formation. In these patients, measurement of such values provides useful information to guide preventive measures., Competing Interests: Compliance with ethical standards Ethical approval No animals were included in the study. All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Conflict of interest None of the authors have any potential conflict of interest. Informed consent Informed consent was obtained from all individual participants included in the study.

Elucidating the material culture of early people in arid Australia and the nature of their environmental interactions is essential for understanding the adaptability of populations and the potential causes of megafaunal extinctions 50-40 thousand years ago (ka). Humans colonized the continent by 50 ka, but an apparent lack of cultural innovations compared to people in Europe and Africa has been deemed a barrier to early settlement in the extensive arid zone. Here we present evidence from Warratyi rock shelter in the southern interior that shows that humans occupied arid Australia by around 49 ka, 10 thousand years (kyr) earlier than previously reported. The site preserves the only reliably dated, stratified evidence of extinct Australian megafauna, including the giant marsupial Diprotodon optatum, alongside artefacts more than 46 kyr old. We also report on the earliest-known use of ochre in Australia and Southeast Asia (at or before 49-46 ka), gypsum pigment (40-33 ka), bone tools (40-38 ka), hafted tools (38-35 ka), and backed artefacts (30-24 ka), each up to 10 kyr older than any other known occurrence. Thus, our evidence shows that people not only settled in the arid interior within a few millennia of entering the continent, but also developed key technologies much earlier than previously recorded for Australia and Southeast Asia.

Lipids are critical to cellular function and it is generally accepted that lipid turnover is rapid and dysregulation in turnover results in disease (Dawidowicz 1987; Phillips et al., 2009; Liu et al., 2013). In this study, we present an intriguing counter-example by demonstrating that in the center of the human ocular lens, there is no lipid turnover in fiber cells during the entire human lifespan. This discovery, combined with prior demonstration of pronounced changes in the lens lipid composition over a lifetime (Hughes et al., 2012), suggests that some lipid classes break down in the body over several decades, whereas others are stable. Such substantial changes in lens cell membranes may play a role in the genesis of age-related eye disorders. Whether long-lived lipids are present in other tissues is not yet known, but this may prove to be important in understanding the development of age-related diseases.

Aim: To study the effect of complex of natural cytokines and antimicrobial peptides (CNCAP) included in preparation Superlymph on growth of multidrug-resistant Mycobacterium tuberculosis CN-37 on the modem of murine peritoneal macrophages (MPh) cultivated in vitro., Materials and Methods: Effect of CNCAP on peritoneal MPh of tuberculosis-susceptible mice C57BL/6 infected by M. tuberculosis CN-37 was studied using ex vivo model. Macrophages were preliminary incubated with CNCAP during one day. M. tuberculosis growth was assessed on 7th day by PCR., Results: Preliminary incubation of infected MPh with CNCAP resulted in inhibition of M. tuberculosis CN-37 growth., Conclusion: Superlymph activates macrophages which lead to enhanced bactericidal action of MPh on M. tuberculosis CN-37.

We propose to form nanoelectrode arrays by deposition of the electrocatalyst through lyotropic liquid crystalline templates onto inert electrode support. Whereas Prussian Blue is known to be a superior electrocatalyst in hydrogen peroxide reduction, carbon materials used as electrode support demonstrate only a minor activity. We report on the possibility for nanostructuring of Prussian Blue by its electrochemical deposition through lyotropic liquid crystalline templates, which is noticed from atomic force microscopy images of the resulting surfaces. The resulting Prussian Blue based nanoelectrode arrays in flow injection analysis mode demonstrate a sub-part-per-billion detection limit (1 x 10(-)(8) M) and a linear calibration range starting exactly from the detection limit and extending over 6 orders of magnitude of H(2)O(2) concentrations (1 x 10(-)(8) to 1 x 10(-)(2) M), which are the most advantageous analytical performances in hydrogen peroxide electroanalysis.

24-h ECG monitoring was performed in healthy subjects and patients with hepatic cirrhosis. Abnormalities rare in healthy individuals and frequent in the patients were registered. Cirrhosis patients presented marked changes in time parameters of cardiac performance.

A study of 59 patients of stable exertion stenocardia (functional class III) revealed an increased content of lipid hydroperoxide in lipoproteids of low and very low density that was associated with an increased level of malonic dialdehyde in of their functional activity, in particular, during physical loads. Finoptin monotherapy did not effect essentially the level of hydroperoxides in lipoproteids of low density, malonic dialdehyde in thrombocytes. Combination of finoptin and alpha-tocopherol reduced essentially the processes of lipid peroxidation, reducing, thus, the functional activity of thrombocytes at rest and loads.

The synthesis and degradation of rat brain synaptosomal proteins were studied in three groups of animals: trained the behaviour pattern in the maze, "pseudo-trained" and control. These processes were assessed from protein specific radioactivity after 1, 3 days and after 1, 3, 6 and 9 weeks following intraventricular injection of 14C-lysine. The experiments showed three fractions differing in overall values of half-life (T50). An increase in specific radioactivity of brain proteins of trained animals was revealed as compared to that in "pseudo-trained" and control rats. T50 was recorded to rise for slow-metabolizing fractions of synaptosomal proteins of trained rats. Participation of synaptosomal proteins in the mechanisms of long-term memory is discussed.

Metabolism of total nonhistone nuclear proteins (NNP) of the rat brain was studied in three groups of animals: trained, pseudotrained and control. Protein synthesis and degradation were estimated by determining NNP specific radioactivity 1, 3, 6 and 9 weeks after the precursor, 14C-lysine, injection. The experimental results indicate that there are two fractions of NNP which differ in their metabolic rates. The half-life of the first "short-living" group of proteins is 5-10 days and that of the second "long-living" one is 18-21 days. It is shown that there is a significant difference in specific radioactivity and metabolic rate between the "short-living" fractions of NNP isolated from the brains of trained or pseudotrained rats, on the one hand, and control rats, on the other hand. Possible participation of the brain total nonhistone nuclear proteins in the mechanisms of alterations of the central nervous system function and learning is discussed.

The authors studied the effect of intraventricular injection of antisynaptosomal gamma-globulin on the protein of synaptosomal proteins in the rat brain cortex. The effect was assesed according to the protein specific radioactivity 2 and 3 hours after injection into animals of 14C-protein hydrolysate of Chlorella. Injection of antisynaptosomal gamma-globulin provoked an increase and reduction in the specific radioactivity of the proteins under study 2 and 3 hours, respectively, after labeled precursor injection. It is assumed that interaction of synaptosomal antibodies with protein synaptosomal antigens produces intense decay of antigens, leading to activation of their synthesis.