bluuebunny/crossref_metadata_2025 huggingface dataset:
Triple Malignancy- Three different Histopathologies in a Single Patient. A Diagnostic Dilemma
Authors:   Post graduate, Department of General Surgery, Sri Devaraj Urs Medical College., Pawar Tejaswini M , P N Sreeramulu , A C Nipun , S Kodaganur , Gopinath Gopinath , G N Manjunath , Prasad CSBR
Published: February 2023

The increasing effectiveness of cancer therapies and the improvement of diagnostic tools have led to better survival rates among cancer patients. This situation has made the problem of developing subse-quent primary tumours more frequent. In our case we discuss about a 70 year old female with three differ-ent primary malignancies. Occurrence of malignancy of the cervix, rectum and bladder is very rare. Key words: Triple malignancies, Bladder carcinoma, Cervical carcinoma, Rectal carcinoma
Hidden sufferers: Anxiety and Depression among Breast feeding mothers
Authors:   Assistant professor, Department of Obstetrics and Gynaecology, Sri Devaraj Urs Medical College., P Vimarshitha , TS Pradeep , KC Lokesh
Published: February 2023

Introduction: Breast feeding is an emotional journey to mother. There is lot of physiological changes which occur during this time. . Postpartum depression can start soon after childbirth or as a contin-uation of antenatal depression and needs to be treated Aims: To assess the prevalence of anxiety and de-pression among breast feeding mothers and various factors associated with anxiety and depression. Settings and Design: Cross sectional study was carried out at Nandagudi Primary Health Centre, MVJ Medical College and Research Hospital field practice area, in rural Bangalore for three months duration from November 2017 to January 2018. Methods and Material: To assess the anxiety, Zung Anxiety scale and to assess depression Edinburgh depression scale (Edinburgh Postnatal Depression scale) were used. Statis-tical analysis used: descriptive statistics like frequencies and percentages and to check difference Independ-ent t test and ANOVA was used. Results: Among 200 breast feeding mothers, around 147(74.5%) belonged to age group of 21-25 years, around 160(80%) were hindu by religion and rest were muslims. Around 90(45%) belonged to nuclear family, 75(37.5%) belonged to joint family and 35(17.5%) belonged to three generation family. Among 200 study participants, 37.5% (75) were having anxiety which was assessed us-ing Zung Anxiety scale. Among 200 study participants, 8% (16) had depression which was assessed using Edinburgh Depression Scale. Conclusions: The prevalence of anxiety and depression from the present study has given the picture of hidden suffers who are neglected because the symptoms coinciding with the normal physiological behaviour. Key-words: Depression, Anxiety, Breast feeding mothers
An Investigation into the change in veterans’ well-being after EquineAssisted Activities
Authors: Dennis Laura , Martin Ruth J. , McGregor Peter K.
Published: February 2023

Equine Assisted Activities are used in a wide variety of situations to improve human well-being. This study investigated the effect of Equine Assisted Activities on the mental well-being of Post-Traumatic Stress Disorder -diagnosed war-veterans using the Warwick-Edinburgh Mental Well-Being Scale over three one-week phases. Veterans self-reported before and after each phase of intervention; the responses from the initial questionnaire were considered to be the baseline for future comparison. After one week (5 days) of equine assisted activities, 31 veterans' responses were significantly more positive than the starting baseline for the majority of questionnaire items. Participation decreased to 17 for week two, and 12 for week three with fewer significant differences recorded. Researchers concluded that results showed that Equine Assisted Activities increased mental well-being, with the biggest differences occurring in the initial intervention phase suggesting one week is an efficient intervention in this context.
APPLICATION OF PHOTOGRAMMETRY FOR DETERMINATION OF VOLUMETRIC JOINT COUNT AS A MEASURE FOR IMPROVED ROCK QUALITY DESIGNATION (RQD) INDEX
Authors:   Goce Delchev University, Shtip, R.N. Macedonia, Adjiski Vancho , Panov Zoran ,   Goce Delchev University, Shtip, R.N. Macedonia, Popovski Risto ,   Goce Delchev University, Shtip, R.N. Macedonia, Karanakova Stefanovska Radmila ,   Goce Delchev University, Shtip, R.N. Macedonia
Published: February 2023

Rock quality designation (RQD) index, provides a general indication of rock mass quality and is widely used in many rock mass classification systems. From the literature review, it is concluded that the RQD methodology has several limitations and one of them is highlighted in this paper with the help of stochastic analysis with Monte Carlo simulation. The purpose of this paper is to improve the results of the RQD index through volumetric joint count (Jv) from accessible surface areas or when drill cores are not available. In this paper, we introduce a low-cost photogrammetric method for rock slope reconstruction with scaled and oriented 3D point cloud, ideally suited for geomechanical analysis. As an outcome, the 3D point cloud is then used to detect the discontinuity sets and to, define their orientation, normal spacing and persistence. Results are then used to calculate the number of joints per m3, which is then used as input in the empirical correlation between the RQD index and the Jv. The main advantage of the proposed methodology is that it is completely based on open-source software.
EFFECT OF PRESSURE ON GOLD CYANIDE LEACHING
Authors:   Freeport McMoRan Inc., USA, Duru N.
Published: February 2023

Although the effect of high oxygen pressure on gold recoveries at elevated slurry temperatures was previously investigated, the sole effect of the pressure at ambient temperatures on cyanide leaching with the presence of nearly enough oxygen for the cyanide reactions to occur has not been found to be studied. This research work was carried out with the objective of investigating the effect of pressure on the recovery of gold from an oxide gold ore and flotation tailing (Carbon in leach (CIL) feed) samples during cyanide leaching process at room temperature. Pressure cyanidation experiments were run in a batch autoclave under different air and nitrogen gas pressures, and pH conditions. Atmospheric bottle roll leach tests for 24 and 8 hours resulted in 90.5% and 66.4% gold recoveries, respectively, whereas 8 hours batch autoclave leach tests under 90 psi air pressure resulted in 88.8% gold recovery from oxide ore samples. Flotation tailing samples leached under atmospheric and under 90 psi air pressure for 8 hours resulted in 16.8% and 34.5% gold recoveries, respectively.
THE EUROPEAN GREEN DEAL AND ITS IMPACT ON THE RAW MATERIAL INDUSTRY
Authors:   University of Mining and Geology “St. Ivan Rilski”, Petrova Vesela
Published: February 2023

Climate changes and environmental degradation are a threat to the existence of Europe and the world. To overcome these challenges, at the end of 2019, the European Commission outlined as a main political line the proposal for the European Green Deal. In most of its aspects, this document is a benchmark for a new mindset that aims to turn the EU in a fair and prosperous society with a modern, resource-efficient and competitive economy in which there will be no net greenhouse emissions in 2050 and the economic growth will not depend on the use of resources. This publication reflects the path from the emergence of the idea of the European Green Deal to the policies pursued today. The academic papers developed in the field are analysed, as well as the prerequisites and challenges that lead to its implementation. An attempt has been made to answer questions related to the main goals of the Green Deal and how these aims correspond to the raw material industry which will be the industry with the most significant consequences in the next decade.
PROGNOSTIC MODEL OF SUBSURFACE CONTAMINATION CAUSED BY NEW EMBANKMENTS ON THE TERRITORY OF MARITSA EAST COAL MINING COMPLEX – CENTRAL SOUTHERN BULGARIA
Authors:   University of Mining and Geology “St. Ivan Rilski”, Stoyanov Nikolay , Dimovski Stefan ,   University of Mining and Geology “St. Ivan Rilski”
Published: February 2023

One of the many environmental problems resulting from electricity generation in thermal power plants is the release of large amounts of solid wastes (coal combustion products). In the absence of effective eco-friendly disposal practices, this waste is accumulated in the form of coal ash embankments or in the excavated parts of the open-cast mines. The so constituted big landfills and surface impoundments emit leachate emissions containing a wide range of conventional pollutants among which, by definition, sulphate ions (SO4) dominate. Using the computer program VS2DI, a numerical model is developed of the conditions for mass transport of pollutants (using the example of SO4) from the designed new embankments for deposition of non-hazardous industrial solid waste from TPP in the area of the internal embankments of Troyanovo-North open-cast mine, part of the Maritsa East Coal Mining Complex. The scheme of convective-diffusion mass transport is employed, taking into account reversible elimination (sorption-desorption), mechanical dispersion and mixing. On the basis of the developed model, a long-term prognosis (100 years) is made for the extent and the degree of subsurface contamination from the new embankments. Based on the model solutions, the retention capacity of the geological foundation and the risk of groundwater pollution are assessed.
Mineralogical and hydraulic characterisation of historic flotation tailings
Authors:   University of Mining and Geology “St. Ivan Rilski”, Angelov Todor
Published: February 2023

A composite flotation tailings sample from historic Medet tailings dam was characterised to understand occurrences of copper and hydraulic properties of the material and to determine if there is an economic benefit of its reprocessing using hydrometallurgical processes. Conventional ICP-OES multi-element scan and carbon and sulphur determination by Leco were followed by sequential copper assay and mineralogical analysis using the Tescan Integrated Mineral Analyser (TIMA) to identify the elemental composition, acid soluble copper and mineral abundance and liberation. The tailings sample contained 0.105% Cu, 0.41 % S and 0.05% C. The analysis of the gangue minerals showed that the bulk of the material is made up of plagioclase feldspar with moderate amounts of K-feldspars and small amounts of mica, chlorite and clay minerals. Copper minerals cuprite and chalcopyrite with minor amounts of covellite and bornite were observed in the mineralogical analysis of the sample by TIMA. Based on the sequential copper assays, it was estimated that approximately 59.8% of copper contained in the sample reports as acid soluble copper. To understand the flow behaviour in the material the main hydraulic properties like hydraulic conductivity and moisture retention capacity were determined.
Reprocessing of magnesite beneficiation waste to recover mineral value and minimise environmental footprint
Authors:   Department of Mechanical and Water Resources Engineering, TEI of Messologi, currently: National Technical University of Athens (NTUA), 15780 NTUA Campus, Zographou, Koukoulis Nikolaos ,   Athens, Greece, Anastassakis Georgios ,   National Technical University of Athens (NTUA), 15780 NTUA Campus, Zographou; Athens, Greece
Published: February 2023

The current paper deals with the re-processing of mineralised mine waste from magnesite processing operations aiming at the recovery of the value. Two cases of mineralised waste were examined. First, waste derived from the removal of “fine” before hand-sorting, with particle size of -40 mm; this waste is usually stockpiled, comprises mostly of relatively coarse particles and is of relatively high-grade in magnesite. The separation methods applied were sorting, sink-float tests and magnetic separation. In general, the results from the application of physical separation methods were satisfactory. Commercial concentrates were obtained from sorting with MgCO3-grade ranging between 94 and 97% MgCO3 and yield about 46%; in case of mixing concentrate with middling, yield rises to 58-64% while grade slightly drops to 91-94%. Equally satisfactory were the results from sink-float separation at sp.gr. 2.88 (grade 95%, yield 45%) but questions arise from the small sp.gr. difference of magnesite and gangues. Finally, the less satisfactory results obtained from magnetic separation (grade around 80-85%, yield 33-65%) may be due to inefficient particles liberation and higher magnetic field is maybe required. Second, mineralised waste consisting of fine particles from size reduction operations were tested. These fines were processed with selective magnetic coating as well as co-agglomeration / magnetic separation techniques. In general, the results of physicochemical processing of fines were very encouraging both on single minerals and their artificial mixtures. In case of magnetic coating, the effect of pH, collector concentration and kerosene dose was studied first on single minerals. Optimum results were obtained for pH=9, dodecylamine solution 4.5x10-5 M and kerosene 2.5 L/t. Tests on artificial mineral mixtures at optimum conditions and magnetic separation at 0.8 A resulted in non-magnetic product with MgCO3-grade higher than 99%. The parameters examined in co-agglomeration / magnetic separation tests were the same as with magnetic coating. Best conditions for co-agglomeration on single minerals were pH=8, dodecylamine 2 kg/t, kerosene 4 L/t. Tests on mineral mixture reveals that the MgCO3-grade increases with dodecylamine but the yield drops.
An Empirical Study on the Role of After-class Service Courses in Stimulating Children's Interpersonal Neuro Synchronization (INS) -- evidence from a primary school in Dongcheng District, Beijing
Authors:   , Jiang Yi , Wang Zhong
Published: February 2023

Interpersonal neural synchronization (INS) is a phenomenon of teaching/learning brain synchronization between teachers and students/students. Existing cognitive neuroscience research has found that the occurrence of INS between teachers and students or between students can significantly promote the learning effect. Moreover, previous studies have shown that full interaction, communication and discussion are the most important factors to stimulate INS. However, due to the restriction of the 40-minute classroom teaching conditions, teachers often cannot let students have full interaction and discussion in the classroom; On the contrary, after-school service courses have more abundant conditions (time and teaching conditions) in this respect. So, compared with the national curriculum, is after-school service curriculum more advantageous in stimulating INS among students? Through a comparative study of the national curriculum with the same teaching content - after-class curriculum, this paper confirms the above conjecture that after-class service curriculum is easier to stimulate INS among students, thus providing empirical evidence from the classroom for the relevant experimental research of INS. At the same time, the research method of this paper also provides a new direction for the experimental conclusion of cognitive neuroscience to enter classroom teaching, that is, to use the effect of real classroom teaching to reverse corroborate the relevant theories and laws of cognitive neuroscience.
Binary Classification of Malignant Mesothelioma: A Comparative Study
Authors: Cheng Ted Si Yuan , Liao Xiyue
Published: February 2023

Malignant mesotheliomas are aggressive cancers that occur in the thin layer of tissue that covers most commonly the linings of the chest or abdomen. Though the cancer itself is rare and deadly, early diagnosis will help with treatment and improve outcomes. Mesothelioma is usually diagnosed in the later stages. Symptoms are similar to other, more common conditions. As such, predicting and diagnosing mesothelioma early is essential to starting early treatment for a cancer that is often diagnosed too late. The goal of this comprehensive empirical comparison is to determine the best-performing model based on recall (sensitivity). We particularly wish to avoid false negatives, as it is costly to diagnose a patient as healthy when they actually have cancer. Model training will be conducted based on k-fold cross validation. Random forest is chosen as the optimal model. According to this model, age and duration of asbestos exposure are ranked as the most important features affecting diagnosis of mesothelioma.
Impact Analysis of a Virtual Stadium: Measuring Sport in the Metaverse
Authors: Baker Bradley J.
Published: February 2023

As sports teams enter the metaverse through launching virtual versions of their home stadiums, there is a pressing need to reimagine the stadium experience and how virtual stadiums differ from their physical counterparts. This review establishes a foundation for crucial conversations that can shape future research and managerial practice amidst an emerging trend in the sport industry.
Professional Sports Organizations and Business Analytics: Monopoly Power vs Debt Financing
Authors: Troilo Mike , Bouchet Adrien
Published: February 2023

In this essay, we consider the factors that explain the reticence of PSOs to be early adopters of analytics. We examine the relatively privileged position that professional sports franchises at the highest echelon in the U.S. and Canada enjoy and compare it the industry dynamics firms face in competitive environments. We remark upon the expansion of the league via debt financing, and why that promotes increased use of analytics. We also offer several propositions about the growth of analytics, and we conclude with some thoughts about what the future may hold for PSOs and analytics.
Women and Climate Change
Authors: Detraz Nicole
Published: February 2023

How ideas of gender and climate change intersect with our path to a livable future.

When you think "climate change," who comes to mind? Who's doing the science, the reporting, the protesting, the suffering? In Women and Climate Change, Nicole Detraz asks where women in the global North figure in the picture, what that means, and why it matters. Her answers fill critical gaps in what we know about the politics of climate change and gender.

Representations of climate change, like perceptions of gender, can make a profound difference in understanding expectations and actions around social, cultural, and political issues. Interviewing women living in the global North who work in the climate change sphere, Detraz examines the crucial links between notions of climate change and gender—in particular, how women are portrayed in climate change debates. Where is their presence or absence recognized? What tasks are they expected to perform? What factors influence their roles? The answers provide a nuanced account of the characteristics, conditions, and positions associated with women's activities in and experiences of climate change—a multifaceted portrayal of women that also demonstrates the generalization and essentializing that can hinder goals of sustainability and gender justice.

Because gender is a social construction, Detraz reminds us, change is possible. Her book offers the suggestion, and the hope, that identifying connections between ideas of gender and climate change might also alter our vision of a livable future.
miR-344d-3p regulates osteogenic and adipogenic differentiation of mouse mandibular bone marrow mesenchymal stem cells
Authors: Cao Wei , Yang Xiaohong , Hu Xiao Hua , Li Jun , Tian Jia , OuYang RenJun , Lin Xue
Published: February 2023

Postmenopausal osteoporosis (POP) is a chronic disease of bone metabolism that occurs in middle-aged and elderly women. POP can cause abnormalities of the skeletal system in the whole body, and the jaw bone is also impacted, affecting the function of the oral and maxillofacial regions. Mandibular bone marrow mesenchymal stem cells (MBMSCs) play an important role in mandibular bone metabolism, and abnormal differentiation of MBMSCs can affect the metabolic balance between new and old bone. MicroRNAs (miRNAs) can induce the differentiation of MBMSCs. In this study, the changes in biological characteristics of mandible and MBMSCs in the bone microenvironment of postmenopausal osteoporosis were firstly analyzed, and then the key miRNAs screened from miRNAs gene chips were sorted out for verification and functional exploration. It was found that miR-344d-3p promoted the osteogenic differentiation of MC3T3-E1 and MBMSCs. It inhibited the adipogenic differentiation of 3T3-L1 and MBMSCs. In addition, Dnmt3a may be the target gene of miR-344d-3p. In conclusion, this study found new biological indicators related to bone metabolism, which are of great significance in the field of bone reconstruction.
Antibacterial Activity of Ulva lactuca against Multidrug Resistant and Betalactamase Producing Isolates from Food Samples- An In-vitro Study
Authors: Manivannan M , Subramanian G
Published: February 2023

Introduction: Antibiotic resistance is a problem of deep scientific concern, both in hospital and community settings. Due the presence of highly resistant microorganisms in food, it may lead to serious health issues to the human beings and other animals also. This can be controlled by novel control methods using natural products. Algae are one such wonderful source that helps in treating such dreadful microorganisms. Ulva lactuca incorporate discrete active compounds, hence, exhibit antibacterial property to control the multidrug resistant bacteria. The present research aims in exploring the potential antibacterial property of such dreadful bacteria. Aim: To evaluate the potential bioactive compound of Ulva lactuca and its antibacterial activity against Multidrug Resistant (MDR) and betalactamase producing food isolates. Materials and Methods: The present pilot in-vitro study was carried out at Arignar Anna Government Arts College, Namakkal, Tamil Nadu, India, in the period of December 2017 to December 2020. Total 18 bacterial isolates were isolated from five retail chicken meat samples. These were then, tested for its antibiotic resistance property using standard antibiotic discs. The algae Ulva lactuca was isolated and extract was prepared using ethanol and chloroform solvents, followed by which the phytochemical studies were performed. These extracts were then tested, against the selected organisms for its potential activity. Results: Among the 12 antibiotics tested, all isolates were resistance to variety of antibiotic classes, mainly aminoglycosides, cephalosporins, and fluoroquinolones and also 55% of the bacteria were able to produce betalactamase enzyme. The ethanol extract of Ulva lactuca was highly active against all isolates and exhibited a range of 10±1.24 mm to 22±1.24 mm inhibition zone. The chloroform extract, exhibited less potency, which exhibited 10±0.816 mm to 13.16±1.027 mm inhibition zone. Each organic solvent showed positive result for following metabolites- alkaloids, carbohydrates, flavonoids, sterols, tannins and terpenoids. Conclusion: The ethanolic extract of Ulva lactuca was very effective against the selected MDR and betalactamase producing food isolates. Therefore, it could be suggested as an antibacterial agent in the future. Further studies are needed to reveal the behavioural mechanisms of this plant and its pharmacological effects.
Effects of Indigenous Farming Practices on Maize Production in Ondo State, Nigeria
Authors: Iseyemi O. J. , Okunlola J. O. , Owolabi K. E.
Published: February 2023

A lot of indigenous knowledge had been lost through the deaths of elderly persons since there is no formal documentation of such knowledge. Old pests and diseases are beginning to resurface due to cropping patterns and adverse climate change impacts. It is in view of this that the study examine the effects of indigenous farming practices on maize production in Ondo State, Nigeria. A multistage sampling technique was used to select 120 maize farmers in the study area. Data was collected using validated questionnaire and were analyzed using means, frequencies, percentages, chi-square and Pearson product moment correlation. Findings from the study revealed that majority (80.8 percent) of the farmers were males, (86.7 percent) above 50 years of age, (87.5 percent) married, (87.5 percent) had formal education, (64.2 percent) were Christians, (25.8) followed by Muslim and (10 percent) traditionalist. A large percentage (75.8 percent) received information on indigenous control methods from their parents and grandparents. The result from the study revealed that there was a significant association between marital status (χ² = 10.06, p < 0.04), religion (χ² = 8.05, p < 0.02), membership of social group (χ² = 14.31, p < 0.00) and the perceived effects of indigenous farming practices of the respondents. Similarly, findings revealed that there was a significant association between income (r = 0.45, p  0.05), farm size (r = 0.13, p  0.05), farming experience (r = 0.11, p  0.05) of the respondents and the perceived effects of indigenous farming practices. There was no significant relationship between extension visitation (χ² = 0.04, p  0.62) and farmers use of indigenous knowledge. There was no significant relationship between indigenous farming practices (r = 0.04, p  0.65) and farmers production practices.
A EROSÃO DO CONSENSO DE ESQUERDA NO PARLAMENTO BRASILEIRO: da Constituinte de 1988 à ascensão de Jair Bolsonaro em 2018
Authors: Santos Frederico Rios C. dos
Published: February 2023

Este trabalho tem o objetivo de verificar como um suposto “consenso de esquerda” vigente no Parlamento brasileiro a partir da Constituinte de 1988 tem se manifestado nos últimos anos. Por meio do confronto de resultados de pesquisas que adotam metodologias baseadas na autodeclaração dos partidos, na opinião de especialistas e na percepção do eleitorado, observou-se um nítido esfacelamento do chamado “recalque de direita”, principalmenteapós a ascensão de Dilma Rousseff ao poder, em 2010, e após as grandes manifestações de junho de 2013, culminando na eleição de Jair Bolsonaro em 2018.
SUJEIÇÃO E SERVIDÃO NO TRABALHO EM PLATAFORMAS DIGITAIS DE TRANSPORTE: um estudo de caso no Rio de Janeiro
Authors: De Lacerda Carelli Rodrigo , Santos de Andrade Maysa
Published: February 2023

O artigo se propõe a investigar se o engendramento da sujeição social e da servidão maquínica, conforme propostos por Maurizio Lazzarato, auxiliam na compreensão da realidade do trabalho em plataformas digitais de transporte de pessoas no Rio de Janeiro. Para isso, analisam-se qualitativamente quatro entrevistas concedidas a partir de um questionário semiestruturado e discorre-se principalmente sobre as formas de controle pelas empresas de plataforma e as cobranças e motivações pessoais desses trabalhadores, concluindo que o uso da subjetividade consolidada na figura do “empresário de si” somada à dessubjetivação e ao impacto dos signos assignificantes na pré-subjetividade dos indivíduos são elementos importantes e complementares na percepção do objeto empiricamenteestudado. O artigo conclui que o homem-máquina da servidão maquínica se perfaz completamente no trabalho em plataforma.
COMPOSIÇÃO DE CLASSE E MIGRAÇÃO PARA ENTENDER O TRABALHO POR PLATAFORMAS:
Authors: Mendonça Mateus , Woodcock Jamie , Grohmann Rafael
Published: February 2023

Este artigo analisa como a migração afeta a composição de classe dos entregadores brasileiros no Reino Unido. Embora pesquisas agora indiquem que a migração desempenha papel importante no trabalho por plataformas no Norte Global, pouco se sabe sobre as maneiras específicas como isso ocorre na prática. Demonstramos como a migração é um aspecto constitutivo desse setor no Norte Global e como a condição de migrante gera experiênciase comunidades comuns, atravessando todos os aspectos dessa indústria, desde a organização do trabalho e as experiências de vida até as formas coletivas de resistência e organização. Para isso, propomos o enquadramento da teoria marxista da composição de classe e a migração, para compreender a formação desse novo setor da classetrabalhadora e seus processos de luta e resistência. Este estudo se baseou em duas pesquisas etnográficas de longo prazo, com a organização coletiva dos entregadores em Londres, e em 13 entrevistas em profundidade.
DEMANDAS DE DIREITOS NO TRABALHO POR PLATAFORMAS DIGITAIS NO BRASIL: O ENFOQUE DOS TRABALHADORES
Authors: Machado Sidnei , Pilan Zanoni Alexandre
Published: February 2023

Neste artigo exploraremos, no contexto do trabalho e regulação do trabalho das plataformas digitais, a configuração do modelo do trabalho autônomo, fora do modelo do assalariamento. O artigo apresenta um conjunto de dados empíricos produzidos no Brasil em 2021, que demonstra as demandas e percepções dos trabalhadores em plataformas sobre direitos na relação de trabalho com as plataformas digitais. Argumentaremos que essas percepções mostram que a aparente autonomia e liberdade do trabalho estão relacionadas ao modelo de gerenciamento desse trabalho. O estudo procura avaliar, numa perspectiva sociojurídica, algumas dimensões da liberdade de trabalho nas plataformas digitais, como contribuição para uma compreensão melhor dessas novas formas de governança do trabalho digital.
Shift from fetal‐type to Alzheimer‐type phosphorylated Tau proteins in SKNSH‐SY 5Y cells treated with okadaic acid
Authors: Dupont-Wallois L. , Sautière P.E. , Cocquerelle C. , Bailleul B. , Delacourte A. , Caillet-Boudin M.L.
Published: July 2002

Tau proteins are abnormally phosphorylated in Alzheimer's disease. Pathological Tau proteins named PHF‐Tau 55, PHF‐Tau 64, and PHF‐Tau 69, are the main constituents of the paired helical filaments (PHF). When treating SKNSH‐SY 5Y cells with okadaic acid (OA), Tau 55 protein was clearly induced whereas Tau 64 protein was only faintly induced. Here, we show that the absence of Tau 69 could be explained by the fact that adult isoforms containing N‐terminal inserts are not detected. Phosphorylation is similar for untreated cellular Tau proteins and fetal Tau proteins, while OA cell treatment transformed fetal‐type into Alzheimer‐type phosphorylated proteins.
Cellular interactions during heart morphogenesis in the Drosophila embryo
Authors: Zaffran Stéphane , Astier Martine , Gratecos Danielle , Guillen Alberto , Sémériva Michel
Published: July 2002

Summry— The formation of the dorsal vessel or heart in a Drosophila melanogaster embryo can be divided into three main steps: i) the determination step allows individualization of heart precursor cells from the dorsal mesoderm. They are arranged in clusters of seven to nine cells, located in each of the eleven segments of the trunk. Preliminary observations suggest that the gene Notch could participate in the choice of fate that the cardioblasts and the pericardial cells will adopt within the cardiogenic region. In the same line, a new gene, whose expression, as revealed by a P‐lacZ insertion, is initiated at gastrulation in the developing mesoderm and becomes restricted within the mesoderm to the myogenic lineages, could participate in the determination of the cardioblasts identity; ii) once the cardioblasts have separated from the dorsal mesoderm, they reorganize to from an epithelial monolayer. The gene coding for the α‐subunit of the transduction protein Go, which is expressed in the cardioblasts shortly before this step, could be involved in this process. Indeed, mutants in the Go α gene are affected in the formation of the cardiac endothelium; and iii) the last step consists of the migration of the cardiac epithelium towards the dorsal midline of the embryo to form the dorsal vessel by apposition of the two layers of cardioblasts. We show that an extracellular matrix component is specifically expressed at the surface of the dorsal vessel and could participate in the interaction between the dorsalmost ectodermal cells and the heart during this migration step.
Direct interaction of nerve growth factor receptor, TrkA, with non‐receptor tyrosine kinase, c‐Abl, through the activation loop
Authors: Koch Alexandra , Mancini Annalisa , Stefan Monica , Niedenthal Rainer , Niemann Heiner , Tamura Teruko
Published: July 2002

The nerve growth factor receptor, TrkA, is essential for the survival and differentiation of neurons in the central and peripheral nervous systems. To understand the molecular principles underlying this differentiation step, we employed a yeast two‐hybrid screening protocol using human TrkA as bait. We isolated c‐Abl as a TrkA‐interacting protein, in addition to known proteins such as phospholipase Cγ and SH2‐B. This interaction was confirmed by an in vitro binding assay using glutathione S‐tranferase–Abl fusion protein. Furthermore, we show here that c‐Abl binds to phosphotyrosine residue(s) in the kinase activation loop of TrkA.
Proadrenomedullin N‐terminal 20 peptide (PAMP) elevates blood glucose levels via bombesin receptor in mice
Authors: Ohinata Kousaku , Inui Akio , Asakawa Akihiro , Wada Keiji , Wada Estuko , Yoshikawa Masaaki
Published: July 2002

We found a potent hyperglycemic effect of proadrenomedullin N‐terminal 20 peptide (PAMP) after intra‐third cerebroventricular administration at a dose of 10 nmol in fasted mice. PAMP has four homologous residues with bombesin (BN), a hyperglycemic peptide. PAMP showed affinity for gastrin‐releasing peptide preferring receptor (GRP‐R) and neuromedin B preferring receptor. The PAMP‐induced hyperglycemic effect was inhibited by [D‐Phe6, Leu‐NHEt13, des‐Met14]‐BN (6–14), GRP‐R specific antagonist, indicating that the hyperglycemic effect is mediated at least in part via GRP‐R. Furthermore, pretreatment of α‐adrenergic blocker inhibited the PAMP‐induced hyperglycemia and hyperglucagonemia, suggesting that the increase of glucagon secretion through α‐adrenergic activation is involved in this hyperglycemic effect of PAMP.
The motility and fertility of golden hamster sperm cultured in BSA‐free medium
Authors: Uto Norihiko , Yamahama Yumi
Published: July 2002

Summry— Before fertilization, capacitation and the acrosome reaction in mammalian spermatozoa must be completed. The motility and fertility of hamster sperm were examined in four kinds of modified Tyrode's solution with or without bovine serum albumin (BSA). Since the presence or absence of polyvinylalcohol (PVA) in the media was another variable, its effect on the sperm motility and fertility was also studied. Sperm were incubated in four different media for up to 6 h at 37.5°C. After 4 h of incubation in the media containing BSA alone or BSA and PVA, sperm were hyperactivated, showing a high sperm motility index (SMI) and were able to fertilize more than 80% of eggs. However, their fertility rapidly decreased during further incubation. In contrast, sperm in the medium containing PVA and no BSA showed low SMI scores after 4 h. However, during the following 2‐h period, the SMI progres‐sively increased and sperm were hyperactivated. Furthermore, the hyperactivated sperm in the PVA containing medium were able to effectively fertilize eggs. Our results indicate that hamster sperm can be capacitated in BSA‐free medium and that capacitation occurs much more slowly in such a medium. We suggest that PVA is a reasonable alternative to BSA in in vitro fertilization and that this slowly progressing system may be a good model for studying various steps in sperm activation.
Improved Cell Growth in Tobacco Suspension Cultures Expressing Vitreoscilla Hemoglobin
Authors: Farrés Judith , Kallio Pauli T.
Published: July 2002

Expression of the gene encoding bacterial hemoglobin (VHb) from Vitreoscilla has been previously used to improve recombinant cell growth and enhance product formation under microaerobic conditions, a common phenomenon in large‐scale cultivations of bacteria. This technology has now been applied to tobacco suspension cultures. Tobacco suspension cultures have been generated from VHb‐expressing tobacco plants. Cell cultures were capable of producing an active hemoglobin. When grown in shake flasks, the cells did not show any lag‐phase and exhibited improved cell growth, compared to controls carrying the parental plasmid.
Protein Focusing in a Conductivity Gradient
Authors: Greenlee Robert D. , Ivory Cornelius F.
Published: July 2002

Conductivity gradient focusing (CGF) is one member of a family of gradient focusing techniques, characterized by two opposing forces which produce a dynamic equilibrium and which are able to simultaneously separate and concentrate proteins. In CGF, the two counteracting forces result from a constant convective flow of buffer opposed by an electric field gradient. This gradient in the electric field is formed by gradually decreasing buffer conductivity, i.e., when a slow‐moving, relatively high conductivity buffer is dialyzed against a low conductivity purge buffer. This paper presents the design of an analytical‐scale CGF device and the results of several experiments with colored proteins, both in free solution and with the use of a 45 μm size‐exclusion (SEC) packing to decrease dispersion. Experimental results with hemoglobin suggest that CGF may one day be capable of resolving proteins with small charge differences. A linear computer model of conductivity gradient focusing is derived, and some suggestions are made for further development of this new electrophoretic method.
The Effect of Rapeseed Oil Uptake on the Production of Erythromycin and Triketide Lactone by Saccharopolyspora erythraea
Authors: Mirjalili Noushin , Zormpaidis Vassilios , Leadlay Peter F. , Ison Andrew P.
Published: July 2002

Saccharopolyspora erythraea was grown in an oil‐based process medium at two different laboratory scales. The initial concentration of rapeseed oil in the medium was shown not to affect the growth, while addition of oil significantly increased erythromycin A production. Increasing the agitation speed at the 2 L scale increased the growth of the culture and the production of erythromycin A but had little effect on the level of oil remaining in the fermentation. Maximum oil utilization of 50% (w/w) was obtained in both 2 and 7 L cultures. Gas chromatography analysis of the process medium showed that there was no accumulation of fatty acids and glycerides during the fermentations. The specific oil utilization by the recombinant strain of S. erythraea was significantly lower compared to the wild‐type strain grown at the same scale and initial oil concentration; the recombinant strain also produced lower concentrations of the novel polyketide, triketide lactone.
Seasonal differences of peak expiratory flow rate variability and mediators of allergic inflammation in non‐atopic adolescents
Authors: Ferdousi Hosne Ara , Munir A. K. M. , Zetterström Olle , Dreborg Sten K. G.
Published: July 2002

Variations in peak expiratory flow (PEF) and serum eosinophil mediators were studied in healthy adolescents. Twenty‐five boys and 31 girls, 11–16 years of age (mean age 14.3 years), were selected and investigated during the birch pollen season of 1995; 45 were also investigated during the autumn of the same year. The PEF was measured twice daily and eosino‐phil mediators in serum and in urine were measured by radioimmunoassay (RIA) once during the birch pollen season and once in autumn. The type values of the daily PEF variation, expressed in amplitude percentage mean, were 6.4 and 3.9%, mean values were 7.35 and 6.74%, and the 95th percentiles were 18 and 14%, during the birch pollen season and autumn, respectively. The 95th percentiles were 41 and 38 µg/l for serum eosinophil cationic protein (s‐ECP), 74 and 62 µg/l for serum eosinophil protein X (s‐EPX), 987 and 569 µg/l for serum myeloperoxidase (s‐MPO), and 165 and 104 µg/mmol for urinary eosinophil protein X/urinary creatinine (u‐EPX/u‐creatinine), during the birch pollen season and autumn, respectively. The levels of the eosinophil mediators decreased significantly from May (n = 56) to November (n = 45), for s‐ECP from a median value of 14 µg/l to 7 µg/l (p= 0.001), for s‐EPX from a median value of 28 µg/l to 20 µg/l (p= 0.001), and for the neutrophil mediator, s‐MPO, from a median value of 440 g/l to 292 g/l (p< 0.001). The PEF variability decreased significantly (p= 0.037), from spring (n = 55; median 8%, 95% confidence interval [CI] 7.8–10.19) to autumn (n = 44; median 6%, 95% CI 6.1–8.9). A significant correlation was found between the levels of s‐ECP and s‐EPX (rs = 0.7, p< 0.001), between s‐ECP and s‐MPO (rs = 0.6, p< 0.001), between s‐EPX and s‐MPO (rs = 0.4, p< 0.005), and between s‐EPX and u‐EPX/u‐creatinine (rs = 0.6, p< 0.0001), in the birch pollen season (n = 56) and in the autumn (n = 45). There was a positive correlation found in PEF variability between the two seasons (n = 43; rs = 0.5, p= 0.0006). No other correlation was found between PEF variability and any other parameters. The difference in the levels of eosinophil mediators between seasons in non‐atopic, healthy children is unexplained. Normal limits for mediators were higher and PEF variability was almost the same as has been reported in adults. When using normal values, seasonal influences should be considered.
Benign lymphoepithelial lesion associated with squamous cell carcinoma of the skin: an immunohistochemical and molecular genetic study
Authors: Miracco Clelia , Schürfeld Karin , Cardone Concetta , Palummo Nazzareno , Pirtoli Luigi , Rubegni Pietro
Published: July 2002

Background: Benign lymphoepithelial lesions (BLEL) are usually found in salivary glands in autoimmune disorders. Some LEL are recognized to already be, or may progress to become, lymphomas. Skin lesions similar to LEL have been described in lymphomas, and are caused by neoplastic lymphocytes which infiltrate adnexal structures. To date, BLEL have not widely been recognized in the skin.

Methods: We describe skin lesions similar to BLELs, at the periphery of squamous cell carcinomas (SCC) in 8 healthy patients, in one of whom the lesion recurred. Immunocharacterization of both epithelial and lymphocytic components and molecular genetic investigation was performed. Polymerase chain reaction (PCR) analysis was done to detect IgH chain gene, and T‐cell receptor β and γ gene rearrangements. Association with Epstein‐Barr virus (EBV) was also tested by in situ hybridization (ISH) for EBV‐encoded RNAs (EBERs).

Results: Epithelial cells showed the immunophenotype of eccrine sweat gland ducts. Infiltrating lymphocytes expressed overwhelming B antigens and CD5. Neither clonal B and/or T proliferations nor EBERs signals were demonstrable.

Conclusions: We observed skin lesions similar to BLELs, showing modifications of sweat gland duct and CD5+, B lymphocytic expansion. In our cases there were no associated autoimmune disorders; the local immunoresponse to SCC might have caused BLEL.
Expression and regulation of the AMP-activated protein kinase–SNF1 (sucrose non-fermenting 1) kinase complexes in yeast and mammalian cells: studies using chimaeric catalytic subunits
Authors: DANIEL Tyrone , CARLING David
Published: July 2002

Mammalian AMP-activated protein kinase (AMPK) and yeast SNF1 (sucrose non-fermenting 1) kinase are members of a highly conserved protein kinase family that plays an important role in energy homoeostasis. AMPK and SNF1 kinase are heterotrimeric complexes consisting of a catalytic subunit and two regulatory subunits. We swapped the C-terminal regulatory domains of the catalytic subunits of AMPK (α) and SNF1 kinase (Snf1) and compared the expression and regulation of these chimaeric proteins with the native catalytic subunits in both mammalian and yeast cells. In mammalian cells, α1—Snf1 yielded a functional kinase complex following co-expression with the yeast regulatory subunits Sip2 and Snf4. Unlike native AMPK, the α1—Snf1 complex was not activated by the stresses that deplete intracellular AMP. Significantly, hyperosmotic stress led to the marked activation of both the α1—Snf1 complex and AMPK, without a detectable change in adenine nucleotide levels, indicating that an alternative, non-AMP-dependent, pathway was responsible for activation. α1—Snf1 was able to restore growth of snf1 mutant yeast on raffinose and phosphorylated the transcriptional repressor protein Mig1. Co-expression of the AMPK trimeric complex in yeast yielded an activity, increased by low glucose, that was similar to native SNF1 kinase. Importantly, expression of AMPK restored growth of a snf1 mutant on raffinose. Our results provide clues to the regulation of AMPK and SNF1 kinase and demonstrate that, in mammalian cells, there are at least two pathways that can activate AMPK, namely one that involves an increase in the AMP/ATP ratio and one that is independent of this ratio. In yeast, the glucose signalling pathway is able to activate AMPK, suggesting that the mammalian and yeast kinase pathways are conserved.
The Src-family tyrosine kinase inhibitor PP1 interferes with the activation of ribosomal protein S6 kinases
Authors: SHAH O. Jameel , KIMBALL Scot R. , JEFFERSON Leonard S.
Published: July 2002

Considerable biochemical and pharmacological evidence suggests that the activation of ribosomal protein S6 kinases (S6Ks) by activated receptor tyrosine kinases involves multiple co-ordinated input signals. However, the identities of many of these inputs remain poorly described, and their precise involvement in S6K activation has been the subject of great investigative effort. In the present study, we have shown that 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP1), a selective inhibitor of the Src family of non-receptor tyrosine kinases, interferes with the activation of 70 and 85kDa S6K gene products (p70S6K1 and p85S6K1) by insulin, insulin-like growth factor 1, sodium orthovanadate and activated alleles of phosphoinositide 3-kinase and H-Ras. PP1 also impedes the activation of AKT/protein kinase B and the extracellular signal-regulated protein kinases 1 and 2 by these various stimuli. Insulin-like growth factor 1 was observed to induce a sustained increase in c-Src autophosphorylation as revealed using anti-phospho-Y416 antisera, but this effect was absent from the cells treated with PP1. To conclude, an activated allele of p70S6K1 is compared with the wild-type allele, resistant to inhibition by PP1 when co-expressed with phosphoinositide-dependent kinase 1 (PDK1), suggesting that PP1 affects p70S6K1 via a PDK1-independent pathway. Thus activation of Src may supply a necessary signal for the activation of p70S6K1 and possibly other S6Ks.
Interaction between the individual isoenzymes of pyruvate dehydrogenase kinase and the inner lipoyl-bearing domain of transacetylase component of pyruvate dehydrogenase complex
Authors: TUGANOVA Alina , BOULATNIKOV Igor , POPOV Kirill M.
Published: July 2002

Protein—protein interactions play an important role in the regulation of enzymic activity of pyruvate dehydrogenase kinase (PDK). It is generally believed that the binding of PDK to the inner lipoyl-bearing domain L2 of the transacetylase component E2 of pyruvate dehydrogenase complex largely determines the level of kinase activity. In the present study, we characterized the interaction between the individual isoenzymes of PDK (PDK1—PDK4) and monomeric L2 domain of human E2, as well as the effect of this interaction on kinase activity. It was found that PDK isoenzymes are markedly different with respect to their affinities for L2. PDK3 demonstrated a very tight binding, which persisted during isolation of PDK3—L2 complexes using size-exclusion chromatography. Binding of PDK1 and PDK2 was readily reversible with the apparent dissociation constant of approx. 10μM for both isoenzymes. PDK4 had a greatly reduced capacity for L2 binding (relative order PDK3>PDK1 = PDK2>PDK4). Monomeric L2 domain alone had very little effect on the activities of either PDK1 or PDK2. In contrast, L2 caused a 3-fold increase in PDK3 activity and approx. 37% increase in PDK4 activity. These results strongly suggest that the interactions between the individual isoenzymes of PDK and L2 domain are isoenzyme-specific and might be among the major factors that determine the level of kinase activity of particular isoenzyme towards the pyruvate dehydrogenase complex.