While conducting recombinant DNA technology procedures, such as DNA purification, agarose gel electrophoresis is often used for identification, characterization and quantification of DNA. The ...collection of data for experiments involving such techniques frequently involves capturing images using systems that are expensive and/or proprietary, such that they are not user-serviceable when they malfunction or become antiquated. In response to these limitations, work was done to replace the authors' existing aging Mac OS-based modular system with open-source software and generic hardware. Several versions of a modular imaging system that can be adjusted to fit nearly all use cases are described. The systems developed can accommodate diverse uses from research laboratories to educational environments where commercial systems could be unaffordable.
A set of easily constructed camera systems for the documentation of electrophoresed agarose gels were developed using inexpensive consumer cameras combined with computers running open-source software. The results observed were comparable with more expensive commercially available documentation systems.
Experiments involving DNA technology often require gel electrophoresis. To document these gels, several low-cost modular systems have been developed. These systems can be adjusted to fit use cases from research to education. #DNA #RaspberryPi #Photos
High throughput drug screening is an established approach to investigate tumor biology and identify therapeutic leads. Traditional platforms use two-dimensional cultures which do not accurately ...reflect the biology of human tumors. More clinically relevant model systems such as three-dimensional tumor organoids can be difficult to scale and screen. Manually seeded organoids coupled to destructive endpoint assays allow for the characterization of treatment response, but do not capture transitory changes and intra-sample heterogeneity underlying clinically observed resistance to therapy. We present a pipeline to generate bioprinted tumor organoids linked to label-free, time-resolved imaging via high-speed live cell interferometry (HSLCI) and machine learning-based quantitation of individual organoids. Bioprinting cells gives rise to 3D structures with unaltered tumor histology and gene expression profiles. HSLCI imaging in tandem with machine learning-based segmentation and classification tools enables accurate, label-free parallel mass measurements for thousands of organoids. We demonstrate that this strategy identifies organoids transiently or persistently sensitive or resistant to specific therapies, information that could be used to guide rapid therapy selection.
Synthetic lethality-an interaction between two genetic events through which the co-occurrence of these two genetic events leads to cell death, but each event alone does not-can be exploited for ...cancer therapeutics
. DNA repair processes represent attractive synthetic lethal targets, because many cancers exhibit an impairment of a DNA repair pathway, which can lead to dependence on specific repair proteins
. The success of poly(ADP-ribose) polymerase 1 (PARP-1) inhibitors in cancers with deficiencies in homologous recombination highlights the potential of this approach
. Hypothesizing that other DNA repair defects would give rise to synthetic lethal relationships, we queried dependencies in cancers with microsatellite instability (MSI), which results from deficient DNA mismatch repair. Here we analysed data from large-scale silencing screens using CRISPR-Cas9-mediated knockout and RNA interference, and found that the RecQ DNA helicase WRN was selectively essential in MSI models in vitro and in vivo, yet dispensable in models of cancers that are microsatellite stable. Depletion of WRN induced double-stranded DNA breaks and promoted apoptosis and cell cycle arrest selectively in MSI models. MSI cancer models required the helicase activity of WRN, but not its exonuclease activity. These findings show that WRN is a synthetic lethal vulnerability and promising drug target for MSI cancers.
The Middle Pleistocene site of Ambrona (Soria, Spain) is a major reference for European Acheulean studies. The origin of the lithic and fauna accumulations at this site was first thought to be ...anthropogenic, but later studies showed that it was mainly natural. The first person to conduct excavations at the Ambrona site was the Marquis of Cerralbo, in 1914; other research groups followed in more recent times (the Howell & Freeman team and the Santonja & Pérez-González team). The digs yielded a great amount of information, but until now it had never been unified. In this paper, we compile all the available published and unpublished excavation documentation from the 1960s to the present. We use these maps and sections to present our spatial study of the LSM (Lower Stratigraphic Member) at the Ambrona site, combining stratigraphic criteria with GIS density and orientation analysis. This study enabled us to define the main concentrations of the LSM, providing an initial contribution to an assessment of their accumulation processes. Most of the concentrations preserved in the ancient shore area of the site display marked orientation patterns which coincide with the direction of the main water flows into the Ambrona wetland. However, random orientation patterns were observed in the central part of the site (Alpha concentration); they may be mostly preserved without undergoing transport processes, as previous taphonomic studies also confirm.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
c-functions in flows across dimensions Lezcano, Alfredo González; Hong, Junho; Liu, James T. ...
The journal of high energy physics,
10/2022, Letnik:
2022, Številka:
10
Journal Article
Recenzirano
Odprti dostop
A
bstract
We explore the notion of
c
-functions in renormalization group flows between theories in different spacetime dimensions. We discuss functions connecting central charges of the UV and IR ...fixed point theories on the one hand, and functions which are monotonic along the flow on the other. First, using the geometric properties of the holographic dual RG flows across dimensions and the constraints from the null energy condition, we construct a monotonic holographic
c
-function and thereby establish a holographic
c
-theorem across dimensions. Second, we use entanglement entropies for two different types of entangling regions in a field theory along the RG flow across dimensions to construct candidate
c
-functions which satisfy one of the two criteria but not both. In due process we also discuss an interesting connection between corner contributions to the entanglement entropy and the topology of the compact internal space. As concrete examples for both approaches, we holographically study twisted compactifications of 4d
N
= 4 SYM and compactifications of 6d
N
= (2, 0) theories.
East Africa has provided the earliest known evidence for Oldowan stone artifacts and hominin-induced stone tool cutmarks dated to ~2.6 million years (Ma) ago. The ~1.8-million-year-old stone ...artifacts from Ain Hanech (Algeria) were considered to represent the oldest archaeological materials in North Africa. Here we report older stone artifacts and cutmarked bones excavated from two nearby deposits at Ain Boucherit estimated to ~1.9 Ma ago, and the older to ~2.4 Ma ago. Hence, the Ain Boucherit evidence shows that ancestral hominins inhabited the Mediterranean fringe in northern Africa much earlier than previously thought. The evidence strongly argues for early dispersal of stone tool manufacture and use from East Africa or a possible multiple-origin scenario of stone technology in both East and North Africa.
The fluvial deposits of the rivers on the Atlantic side of the Iberian Peninsula preserve a number of locations with Acheulean industry, frequently without associated fauna. These remains are ...especially concentrated on middle terraces, which can be dated to about MIS 11. The most common raw material is quartzite and these industries are characterized by the presence of bifaces, cleavers and tools made from medium and large rock flakes (>10 cm). The technological characteristics of these Acheulean localities and their chronological separation from the recognised human occupation of the Peninsula during the Lower Pleistocene (Atapuerca, Guadix-Baza depression, Murcia) by some 500 ka or more, support the possible African origin of the European Middle Pleistocene Acheulean techno-complex and the hypothesis that Gibraltar was the access route.
The identification of anthropogenically-modified carnivoran bones in archaeological sites is rare in Pleistocene contexts, especially in the most ancient periods. Neanderthal groups have clearly ...shown a great variety of subsistence activities and the use of carnivoran resources, until rare, is also present in some archaeological sites.
However, the identification of the bone surface modifications (BSM) that allow us to infer the presence of anthropogenic marks in faunal remains are usually difficult to be differentiate among other BSM. Recently, several statistical and computing techniques have been developed to differentiate among different types of BSM in an objective way.
To date, the most powerful approach is the use of Convolutional Neural Networks, which are the essential part of what is referred to as Deep Learning. In this work, ResNet50 and Inception V3 models are used through transfer learning. The algorithm architecture reaches an accuracy of >96.3% when differentiating among experimental trampling, cut and tooth marks. Once the transfer models were re-trained with the experimental BSM, they were used to classify several archaeological BSM previously identified as cut marks by human analysts. These BSM have been found on a bear ulna and on a hyena phalanx, both recovered at the Navalmaíllo Rock Shelter (Madrid, Spain).
The BSM located on the hyaena phalanx have been identified as cut marks with a high probability while marks on the bear ulna are non-anthropogenic. This bone adds to the existing sample of anthropogenically-modified carnivoran elements by Neanderthal populations and hint to use of carnivore pelts by Neanderthals.
•Computer vision allows correct analysis of Neanderthal cut marks on a hyena phalanx.•Computer vision also allows to interpret correctly trampling marks on a bear ulna.•These cut marks are clearly related to skinning activities of the hyena pelt.•This evidence is the first related to skinning of a hyena in the Pleistocene record.
This paper presents for the first time an experimental protocol for the assessment of use-wear produced when using Precambrian and metamorphic white Naibor Soit quartzite (NQ) flakes. NQ is the most ...recurrent raw material from the archaeological sites of the Olduvai Gorge during the Early Stone Age (ESA). The objective of this study is to provide a preliminary description of the experimentally produced use-wear traces that can be applied to the analysis of sites like the Acheulean site of Thiongo Korongo (TK, Olduvai Gorge, Tanzania) or other sites from Olduvai where NQ was used to tool production.
This experimental protocol incorporates a broad range to tasks including plant processing (underground storage organs USOs, wood, herbaceous plants, and canes) and carcass processing (butchery and bone processing). The most novel activity of this experimental protocol is the processing of USOs. For this we have replicated different steps of tuber processing including the cutting, peeling, and scraping of five varieties of USOs (Beta vulgaris, Daucus carota, Ipomoea batatas, Pastinaca sativa and Zingiber,officinale) with differences in hardness, fibrosity, water content, and peel regularity.
After analysing micro and macro-wear traces on the experimental flakes, several criteria for distinguishing between different activities (scraping, cutting, peeling, sawing, cutting, butchery) and the different materials being processed were identified. These criteria are based on the presence, continuity, and morphology of macro-scars along with the presence, distribution, nature, and intensity of different micro traces (micro-scars, attrition, striations, pits, rounding, polish). Additionally, we have identified several processes that limit the formation of traces, including the tendency of some activities to weaken NQ edges and shorten the duration of use.
•First experimental traceological study made with Naibor Soit quartzite, the most representative raw material from the Early Stone Age sites at the Olduvai Gorge (Tanzania) (1, 2, 3, 4; Jones, 1994; Kyara, 1996, 1999; Santonja et al., 2014; Díez-Martín et al., 2015; Rubio-Jara et al., 2017; McHenry and de la Torre, 2018).•Full range of experiments including, among others, butchery, woodworking and processing of tubers (12, 13).•Assessment of the parameters for the interpretation of the formation of use related traces on Naibor Soit quartzite.•Base description and interpretation parameters for the study of the function of the lithic industry elaborated with Naibor Soit quartzite in the archaeological sites of the Olduvai Gorge.
Two clearly differentiated techno-complexes can be recognised in the Iberian Peninsula during the second half of the Middle Pleistocene: the Acheulean and the Middle Palaeolithic. In this paper we ...present the current state of research on both technological entities, and propose that they represent two different industrial traditions. The Acheulean, a techno-complex that originated and developed in Africa, is considered to have reached Western Europe via Gibraltar, and developed only to a limited extent. In contrast, relict populations with a different technological tradition would have been present on the European continent since the late Early Pleistocene and developed a technological tradition was based on the development of chaînes operatoire of débitage. From MIS 10 on these industries had reached a high degree of complexity and diversity.
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