RESUMO
Thousands of energy-aware sensors have been placed for monitoring in a variety of scenarios, such as manufacturing, control systems, disaster management, flood control and so on, requiring time-critical energy-efficient solutions to extend their lifetime. This paper proposes reinforcement learning (RL) based dynamic data streams for time-critical IoT systems in energy-aware IoT devices. The designed solution employs the Q-Learning algorithm. The proposed mechanism has the potential to adjust the data transport rate based on the amount of renewable energy resources that are available, to ensure collecting reliable data while also taking into account the sensor battery lifetime. The solution was evaluated using historical data for solar radiation levels, which shows that the proposed solution can increase the amount of transmitted data up to 23%, ensuring the continuous operation of the device.
RESUMO
This paper analyzes the behavior of a miniature 3D wind sensor designed for Mars atmosphere. The sensor is a spherical structure of 10 mm diameter divided in four sectors. By setting all the sectors to constant temperature, above that of the air, the 3D wind velocity vector can be measured. Two sets of experiments have been performed. First, an experimental campaign made under typical Mars conditions at the Aarhus Wind Tunnel Simulator is presented. The results demonstrate that both wind speed and angle can be efficiently measured, using a simple inverse algorithm. The effect of sudden wind changes is also analyzed and fast response times in the range of 0.7 s are obtained. The second set of experiments is focused on analyzing the performance of the sensor under extreme Martian wind conditions, reaching and going beyond the Dust Devil scale. To this purpose, both high-fidelity numerical simulations of fluid dynamics and heat transfer and experiments with the sensor have been performed. The results of the experiments, made for winds in the Reynolds number 1000-2000 range, which represent 65-130 m/s of wind speed under typical Mars conditions, further confirm the simulation predictions and show that it will be possible to successfully measure wind speed and direction even under these extreme regimes.
RESUMO
BACKGROUND: The proteome of mitochondria comprises mostly proteins that originate as precursors in the cytosol. Before import into the organelle, such proteins are exposed to cytosolic quality control mechanisms. Multiple lines of evidence indicate a significant contribution of the major cytosolic protein degradation machinery, the ubiquitin-proteasome system, to the quality control of mitochondrial proteins. Proteins that are directed to the mitochondrial intermembrane space (IMS) exemplify an entire class of mitochondrial proteins regulated by proteasomal degradation. However, little is known about how these proteins are selected for degradation. RESULTS: The present study revealed the heterogeneous cytosolic stability of IMS proteins. Using a screening approach, we found that different cytosolic factors are responsible for the degradation of specific IMS proteins, with no single common factor involved in the degradation of all IMS proteins. We found that the Cox12 protein is rapidly degraded when localized to the cytosol, thus providing a sensitive experimental model. Using Cox12, we found that lysine residues but not conserved cysteine residues are among the degron features important for protein ubiquitination. We observed the redundancy of ubiquitination components, with significant roles of Ubc4 E2 ubiquitin-conjugating enzyme and Rsp5 E3 ubiquitin ligase. The amount of ubiquitinated Cox12 was inversely related to mitochondrial import efficiency. Importantly, we found that precursor protein ubiquitination blocks its import into mitochondria. CONCLUSIONS: The present study confirms the involvement of ubiquitin-proteasome system in the quality control of mitochondrial IMS proteins in the cytosol. Notably, ubiquitination of IMS proteins prohibits their import into mitochondria. Therefore, ubiquitination directly affects the availability of precursor proteins for organelle biogenesis. Importantly, despite their structural similarities, IMS proteins are not selected for degradation in a uniform way. Instead, specific IMS proteins rely on discrete components of the ubiquitination machinery to mediate their clearance by the proteasome.
Assuntos
Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Citosol/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Complexo de Endopeptidases do Proteassoma , Proteólise , Saccharomyces cerevisiae/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , UbiquitinaçãoRESUMO
Controls of surface potential have been proposed to accelerate the time response of MOX gas sensors. These controls use temperature modulations and a feedback loop based on first-order sigma-delta modulators to keep constant the surface potential. Changes in the surrounding gases, therefore, must be compensated by average temperature produced by the control loop, which is the new output signal. The purpose of this paper is to present a second order sigma-delta control of the surface potential for gas sensors. With this new control strategy, it is possible to obtain a second order zero of the quantization noise in the output signal. This provides a less noisy control of the surface potential, while at the same time some undesired effects of first order modulators, such as the presence of plateaus, are avoided. Experiments proving these performance improvements are presented using a gas sensor made of tungsten oxide nanowires. Plateau avoidance and second order noise shaping is shown with ethanol measurements.
RESUMO
Neuroendocrine tumors (NEN) are rarely diagnosed neoplasms, which frequency is estimated on about 35 cases/100 000. During last 30 years the number of NEN's new diagnosis increased five-times and nowadays reaches 5,86/100 000/year. It is partially associated with increasing detectability of these tumors. Such diagnostic methods as capsule endoscopy and positron emission tomography are becoming increasingly widely accessible. Though, one should bear in mind that in case of patients diagnosed with NEN cooperation between specialists in different fields of medicine, such as endocrinology, nuclear medicine, oncology, radiology, internal medicine and surgery is needed.
Assuntos
Tumores Neuroendócrinos/diagnóstico , HumanosRESUMO
There is a steady increase in the number of neuroendocrine tumors. Although the knowledge about this tumors' biology is increasing, they are still diagnosed in advanced stadium, when surgical treatment is not an option. One of the treatment methods which are available in this group of patients is peptide receptor radionuclide therapy, which should be considered in selected patients. This treatment is usually well tolerated by patients, though severe adverse events may occur, such as myelosuppression or renal failure.
Assuntos
Tumores Neuroendócrinos/tratamento farmacológico , Radioisótopos/uso terapêutico , Somatostatina/análogos & derivados , Humanos , Radioisótopos/efeitos adversos , Insuficiência Renal/induzido quimicamenteRESUMO
Paracoccus kondratievae NCIMB 13773(T), isolated from the maize rhizosphere, carries a large (95,049 bp) plasmid pKON1, whose structure has been significantly influenced by transposition. Almost 30% of the plasmid genome is composed of complete or truncated insertion sequences (ISs), representing seven IS families. The ISs are accompanied by numerous genes and gene clusters commonly found in bacterial chromosomes, encoding, among others, (i) a putative type III secretion system of the Rhizobiales-T3SS family, (ii) a type I restriction-modification system associated with the anti-codon nuclease (ACNase) gene prrC and (iii) OstA and OstB proteins involved in trehalose synthesis. The backbone of pKON1 is composed of replication and partitioning modules conserved in several large alphaproteobacterial replicons, including secondary chromid pAMI6 of Paracoccus aminophilus JCM 7686 and chromosome 2 (chromid) of Rhodobacter sphaeroides 2.4.1. pKON1 also contains a toxin-antitoxin system of the hipAB family, whose presence precludes removal of the plasmid from bacterial cells. This system, unlike two other related hipAB-family loci originating from plasmid pAMI8 and the chromosome of Paracoccus aminophilus JCM 7686, is highly efficient and permits very stable maintenance of a heterologous replicon in various hosts.
Assuntos
Toxinas Bacterianas/genética , Paracoccus/genética , Plasmídeos/genética , Sequência de Aminoácidos , Composição de Bases , Sequência de Bases , Cromossomos Bacterianos/genética , Loci Gênicos , Dados de Sequência Molecular , Replicon , Análise de Sequência de DNARESUMO
Cell culture is a critical platform for numerous research and industrial processes. However, methods for transporting cells are largely limited to cryopreservation, which is logistically challenging, requires the use of potentially cytotoxic cryopreservatives, and can result in poor cell recovery. Development of a transport media that can be used at ambient temperatures would alleviate these issues. In this study, we describe a novel transportation medium for mammalian cells. Five commonly used cell lines, (HEK293, CHO, HepG2, K562, and Jurkat) were successfully shipped and stored for a minimum of 72 hours and up to 96 hours at ambient temperature, after which, cells were recovered into standard culture conditions. Viability (%) and cell numbers, were examined, before, following the transport/storage period and following the recovery period. In all experiments, cell numbers returned to pretransport/storage concentration within 24-48 hours recovery. Imaging data indicated that HepG2 cells were fully adherent and had established typical growth morphology following 48 hours recovery, which was not seen in cells recovered from cryopreservation. Following recovery, Jurkat cells that had been subjected to a 96 hours transport/storage period, demonstrated a 1.93-fold increase compared with the starting cell number with >95% cell viability. We conclude that CellShip® may represent a viable method for the transportation of mammalian cells for multiple downstream applications in the Life Sciences research sector.
Assuntos
Técnicas de Cultura de Células , Sobrevivência Celular , Criopreservação , Temperatura , Humanos , Criopreservação/métodos , Animais , Técnicas de Cultura de Células/métodos , Células Hep G2 , Células Jurkat , Meios de Transporte , Células CHO , Cricetulus , Meios de Cultura , Células HEK293 , Células K562RESUMO
This dataset compiles radiocarbon dates received for botanical macroremains and animal bones from domestic and ritual pits and human graves unearthed during excavations at the archaeological site of Kaldus (Poland) that can be related to the Funnel Beaker culture (TRB). Prior to radiocarbon dating by accelerator mass spectrometry (AMS), plant macroremains were checked against diagnostic attributes of species identification by standard paleobotanical analysis. The dataset contains already published (n = 4) and new (n = 10) radiocarbon dates that were used to establish the absolute chronology of the TRB habitus at Kaldus and its diachronic spatial organization. This dataset serves as an archive for future studies focusing on the TRB settlement pattern and organization in the region of modern Poland. It also has a utility to be reused in archaeological and chronological research on the movement of copper metalwork and the gradual spread of human cremation rite in the region.
RESUMO
Small GTPases play essential roles in the organization of eukaryotic cells. In recent years, it has become clear that their intracellular functions result from intricate biochemical networks of the GTPase and their regulators that dynamically bind to a membrane surface. Due to the inherent complexities of their interactions, however, revealing the underlying mechanisms of action is often difficult to achieve from in vivo studies. This review summarizes in vitro reconstitution approaches developed to obtain a better mechanistic understanding of how small GTPase activities are regulated in space and time.
Assuntos
Proteínas Monoméricas de Ligação ao GTP , Proteínas Monoméricas de Ligação ao GTP/metabolismoRESUMO
The detection of dairy processing is pivotal to our understanding of ancient subsistence strategies. This culinary process is linked to key arguments surrounding the evolution of lactase persistence in prehistory. Despite extensive evidence indicating the presence of dairy products in ceramics in the European Neolithic, questions remain about the nature and extent of milk (and lactose) processing and consumption. In order to investigate past patterns of dairy processing, here we analyse ancient proteins identified from Late Neolithic Funnel Beaker ceramics, scrutinizing the principle that curd and whey proteins partition during the production of dairy foods from milk. Our results indicate the presence of casein-rich dairy products in these vessels suggesting the creation of curd-enriched products from raw milk. Moreover, this analysis reveals the use of multiple species for their dairy products in the Late Neolithic, adding to a growing body of evidence for the period. Alongside palaeoproteomic analysis, we applied well-established lipid residue analysis. Differential interpretations between these two approaches show that palaeoproteomics is especially useful where the effects from isotope mixing may underestimate the frequency of dairy products in archaeological ceramics, highlighting the potential utility of a multi-stranded approach to understand life histories of vessel use.
RESUMO
Accumulating evidences suggest that foods that were regularly consumed during the human primates and evolution, in particular during the Paleolithic era (2.6-0.01 x 10(6) years ago), may be optimal for the prevention and treatment of some chronic diseases. It has been postulated that fundamental changes in the diet and other lifestyle conditions that occurred after the Neolithic Revolution, and more recently with the beginning of the Industrial Revolution are too recent taking into account the evolutionary time scale for the human genome to have completely adjust. In contemporary Western populations at least 70% of daily energy intake is provided by foods that were rarely or never consumed by Paleolithic hunter-gatherers, including grains, dairy products as well as refined sugars and highly processed fats. Additionally, compared with Western diets, Paleolithic diets, based on recently published estimates of macronutrient and fatty acid intakes from an East African Paleolithic diet, contained more proteins and long-chain polyunsaturated fatty acids, and less linoleic acid. Observational studies of hunter-gatherers and other non-western populations lend support to the notion that a Paleolithic type diet may reduce the risk of cardiovascular disease, metabolic syndrome, type 2 diabetes, cancer, acne vulgaris and myopia. Moreover, preliminary intervention studies using contemporary diet based on Paleolithic food groups (meat, fish, shellfish, fresh fruits and vegetables, roots, tubers, eggs, and nuts), revealed promising results including favorable changes in risk factors, such as weight, waist circumference, C-reactive protein, glycated haemoglobin (HbAlc), blood pressure, glucose tolerance, insulin secretion, insulin sensitivity and lipid profiles. Low calcium intake, which is often considered as a potential disadvantage of the Paleolithic diet model, should be weighed against the low content of phytates and the low content of sodium chloride, as well as the high amount of net base yielding vegetables and fruits. Increasing number of evidences supports the view that intake of high glycemic foods and insulinotropic dairy products is involved in the pathogenesis and progression of acne vulgaris in Western countries. In this context, diets that mimic the nutritional characteristics of diets found in hunter-gatherers and other non-western populations may have therapeutic value in treating acne vulgaris. Additionally, more studies is needed to determine the impact of gliadin, specific lectins and saponins on intestinal permeability and the pathogenesis of autoimmune diseases.
Assuntos
Doença Crônica/prevenção & controle , Dieta/história , Alimentos Orgânicos/história , Alimento Funcional/história , Evolução Biológica , Ingestão de Energia , História Antiga , Humanos , Valor NutritivoRESUMO
Fused deposition modeling (FDM) is one of the most accessible additive manufacturing (AM) technologies for processing polymeric materials. It allows processing most of thermoplastic polymers, with polyethylene terephthalate glycol-modified (PET-G) and polylactic acid (PLA). AM parts tend to display anisotropic behavior because of layer-by-layer fabrication and various technological parameters that can be set for 3D print, so it is hard to predict and analyze how the manufactured parts would behave under load. This research presents results of classic tensile strength tests performed on 57 PET-G specimens and 57 PLA specimens manufactured with varying technological parameters such as: printing temperature, print orientation, layer height, and infill percentage. Afterward, a comparative analysis is performed, proposing specific tensile strength (STS) as a benchmark to determine how 3D printed parts strength is varying due to beforementioned parameters, eliminating bias induced by varying weight of specimens. The biggest relative increase of UTS and the biggest relative decrease of STS was noted for variable infill percentage (increasing infill-PLA: 37.27% UTS increase and 30.41% STS decrease; PET-G: 24.42% UTS increase and 37.69% STS decrease). The biggest relative increase of STS between examined parameters was observed for both materials as the printing temperature was increased (27.53% for PLA and 12.69% for PET-G). Similar trends in STS changes were observed for both materials. Obtained data shows which FDM AM parameters are the most important to obtain the biggest UTS of manufactured parts, and those do not overlap with parameters needed to obtain optimal strength-to-weight ratio.
RESUMO
The current scientific literature lacks an adequate description of hardware used to machine timber. Traditional woodworking and metals fabrication consists of tungsten carbide (TC) inserts. In this work, the authors investigate the influence of cutting tool geometry on the resulting surface roughness of timber samples. A variety of wood types were used in these studies to provide broad information on the correlation between the cutting tools used and resulting surface morphology. The cutting tools were prepared on a computer numerical control (CNC) lathe and roughness average (Ra) and average maximum peak to valley height of the profile (Rz) parameters were measured by contact stylus. The tip radius of the TC inserts used was determined to be the most significant factor that impacted Ra and Rz. In summary, we found that the tip radius of the TC insert was inversely proportional to the roughness level, indicating that a flatter TC insert cutting end results in a smoother wood surface.
RESUMO
Neuroendocrine tumors (NETs, originally termed "carcinoids") create a relatively rare group of neoplasms with an approximate incidence rate of 2.5 to 5 cases per 100 000 persons. Roughly 30% to 40% of subjects with NETs develop carcinoid syndrome (CS), and 20% to 50% of subjects with CS are diagnosed with carcinoid heart disease (CaHD). The long-standing exposure to high serum serotonin concentration is one of the crucial factors in CaHD development. White plaque-like deposits on the endocardial surface of heart structures with valve leaflets and subvalvular apparatus thickening (fused and shortened chordae; thickened papillary muscles) are characteristic for CaHD. NT pro-BNP and 5-hydroxyindoleacetic acid are the 2 most useful screening markers. Long-acting somatostatin analogs are the standard of care in symptoms control. They are also the first-line treatment for tumor control in subjects with a metastatic somatostatin receptor avid disease. In cases refractory to somatostatin analogs, several options are available. We can increase a somatostatin analog to off-label doses, add telotristat ethyl or administer peptide receptor radionuclide therapy. Cardiac surgery, which mainly involves valve replacement, is presently the most efficient strategy in subjects with advanced CaHD and can relieve unmanageable symptoms or be partly responsible for better prognosis.
RESUMO
Background: Although thyrotropin (TSH) receptors are found in many nonthyroid tissues, we know little about the direct action of TSH on these receptors. Patients after total thyroidectomy for differentiated thyroid cancer (DTC) provide an interesting model for studying this issue. The administration of exogenous TSH in patients with an established thyroid state on levothyroxine (LT4) treatment allows us to study the effect of elevated TSH concentrations independent of thyroid status on the function of various organs, including the kidneys. The aim of this study was to assess the effects of the administration of recombinant human TSH (rhTSH) on renal perfusion and glomerular filtration in this group of patients. Methods: The study included 24 patients after total thyroidectomy due to DTC, without concomitant diseases, receiving only LT4 who qualified for radioiodine treatment (RIT). For two consecutive days, the patients received rhTSH and subsequently the RIT. Clinical and biochemical evaluation of thyroid and renal function was carried out before and 24 hours after the second dose of rhTSH and before the RIT. On the sixth day of hospitalization, the patients' glomerular filtration rate was re-evaluated. Kidney perfusion was assessed using color Doppler ultrasound imaging before and 24 hours after the second dose of rhTSH and before the RIT. Results: The administration of rhTSH to patients after total thyroidectomy due to DTC caused significant deterioration of renal perfusion after the second dose of rhTSH before the RIT, which was followed by a significant reduction in glomerular filtration. Furthermore, rhTSH did not significantly affect the hemodynamic parameters that could worsen renal function. Conclusions: This study indicates that TSH alone, independent of thyroid hormone concentrations, can influence renal perfusion and renal function.
Assuntos
Rim/efeitos dos fármacos , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Tireotropina/farmacologia , Tiroxina/farmacologia , Adulto , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/fisiopatologia , Neoplasias da Glândula Tireoide/radioterapia , Tireotropina/uso terapêutico , Tiroxina/uso terapêuticoRESUMO
BACKGROUND: The aim of this study was to assess the prevalence of long bone metastases in renal cancer patients and to evaluate their utility as predictors of survival in this group. MATERIAL AND METHODS: This retrospective study included 20 patients with metastatic renal cancer and bone metastases. The patients were referred for regular bone scintigraphy in order to assess disease spread in the skeleton. The patients were divided into two groups: those with 1) metastases in the skeleton (including long bones) and those with 2) metastases in the axial skeleton only. RESULTS: Bone scintigraphy imaging was performed regularly up to 81 months from the first positive bone scan. During that time 11 deaths (8 among patients with long bone lesions) were recorded. Kaplan-Meyer curves showed that patients with long bone metastases tend to have lower survival probability in comparison to the ones with metastases in other bones. CONCLUSIONS: Bone metastases localization seems to influence survival in patients with renal cancer. Long bone-involving spread of the disease is associated with worse survival probability than the spread to the other bones.