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The discovery of a planetary candidate orbiting the habitable zone of our closest neighbor, Proxima Centauri (Gl 551), shook the planetary community as few other discoveries have done in recent years. It not only showed that the nearest star to the Sun could host a planetary system but also that, given the right conditions, it could host a habitable rocky planet. 2020 brought back the attention to Proxima with the announcement of a second planetary candidate in the system, the confirmation of Proxima b, using ESPRESSO, and the suggestion of a third, very low mass. Now, after an intense observational campaign, we can confidently say there’s a third companion with just one quarter of the mass of the Earth. Proxima d is one of the lightest exoplanets known to date. It orbits its parent star at 0.029 AU, with a period of 5.12 days. It’s induced RV semi-amplitude, of just 39 cm/s on a V-mag 11 star, highlights the capabilities of the ESPRESSO spectrograph, installed at the VLT telescope array of the Paranal observatory. The signal has an amplitude that is just 1/5 of the amplitude of the activity-induced radial velocity signal, which shows that, under the right conditions, current techniques can detect planetary signals much smaller than activity signals. The discovery of Proxima d opens the door to the characterization of the population of very low mass planets of the solar neighborhood. It shows that radial velocity studies are now capable of detecting exoplanets with masses similar to the Earth and much smaller.&nbsp

Proxima meloi sp. nov. (Figs 33–51, 56, 57) Diagnosis. Forewing (Fig. 36) without dark maculae. Male pygofer (Fig. 39), in lateral view, with apical portion rounded, not curved or folded inwardly. Subgenital plate (Fig. 40), in ventral view, with inner margin strongly expanded. Style (Fig. 42), in lateral view, with blade approximately straight, higher at base and narrowing towards the apex; ventral margin weakly serrated. Aedeagus (Figs 43, 44) with atrial processes not bifid and as long as shaft; shaft without processes; apex bifid into acute processes directed anteriorly. Measurements (mm). 11.8–12.9 mm (male); 12.8–13.5 mm (female). Coloration. As in generic description. External morphology. Crown-face transition (Fig. 34) with transverse striae only close to the eye, smooth on the median portion. Forewing (Fig. 36) with extra-numerary veins on discal, subapical and apical cells, sometimes apical half almost reticulate. Other characters as in generic description. Male terminalia. Sternite VIII (Fig. 37), in ventral view, approximately 1.4 times wider than long, strongly convex; lateral margins parallel; posterior margin widely rounded, emarginated medially. Valve (Fig. 38), in ventral view, approximately 2.7 times wider than long; posterior margin slightly excavated medially. Pygofer (Fig. 39), in lateral view, approximately 1.8 times longer than high; internal surface of lateral lobe with a thickening of the integument at anterodorsal portion; ventral margin rounded and expanded ventrally; posterodorsal and posteroventral margins approximately straight and strongly convergent at apex; apex rounded. Subgenital plate (Fig. 39), in lateral view, strongly curved dorsally; in ventral view (Fig. 40), 2.5 times longer than wide; subtriangular, outer margin slightly excavated; inner margin expanded and widely rounded; apex rounded. Connective (Fig. 41), in dorsal view, large and wide; arms 1.2 times longer than stalk; anterior margin deeply excavated. Style (Fig. 41), in dorsal view, with lateral lobe rounded; in lateral view (Fig. 42), blade approximately straight, higher at base and narrowed towards apex; ventral margin weakly serrated; apex acute and curved dorsally. Aedeagus (Figs 43, 44) with preatrium reduced; dorsal apodeme moderately developed with dorsal margin deeply excavated, lateral margins slightly produced laterally; atrial processes long, wide at base and narrowing towards apex, as long as the shaft, apex rounded; shaft long and tubular, widely curved anterodorsally; apex bifid (from apical third of shaft) into acute processes directed anteriorly. Female terminalia. Sternite VII (Fig. 45), in ventral view, approximately 1.4 times wider than long; posterolateral angle rounded; posterior margin slightly excavated near lateral angles, median portion strongly projected posteriorly with distinct median lobe deeply excavated medially. Pygofer (Fig. 46), in lateral view, approximately 1.3 times longer than high; macrosetae distributed at ventral half and apex; apex rounded. First valvifer (Fig. 47), in lateral view, subelliptic, slightly higher than wide; posterior margin truncated. First valvula (Figs 47, 48), in lateral view, approximately 8.6 times longer than high; apex subacute. Second valvula (Figs 49, 50), in lateral view, approximately 10.5 times longer than high; dorsal margin with four rounded teeth, basal tooth larger than others and apical tooth reduced; apex rounded.Second valvifer (Fig. 51), in lateral view, approximately 2.2 times higher than wide.Gonoplac (Fig. 51), in lateral view, approximately 3.6 times longer than high. Other characters as in generic description. Etymology. The new species is named in tribute to Dr. Gabriel A. R. Melo, Hymenoptera specialist and one of the collectors of the type-series. Material examined: Holotype male: “ Brasil, Bahia, 10 Km a\ NE de Encruzilhada,\ 15. 483ºS 40.824ºW,\ 830m 15.xii.2012,\ G. Melo & P. Grossi \Arm luminosa” (DZUP). Paratypes: Bahia: 2 ♂, 3 ♀, same data as holotype (DZUP); 9 ♂, 1 ♀, “ Brasil, Bahia, 6 Km a\ SE de Encruzilhada,\ 15. 567ºS 40.870ºW,\ 910m 16.xii.2012,\ G. Melo & P. Grossi \ Arm luminosa” (4 ♂, 1 ♀, DZRJ DZRJ-AUCH 0232, 0233, 0234, 0235, 0236; 1 ♂, MZSP; 4 ♂, DZUP); 4 ♂, 2 ♀, “ Brasil, Bahia,\ Encruzilhada \ XII.1980 \ M. Alvarenga leg.” (DZUP); 2 ♂, 1 ♀, “ Brasil, Bahia,\ Encruzilhada \ XI.1975 \ M. Alvarenga leg.” (MNRJ); 2 ♂, 2 ♀, “ Encruzilhada \ BA. Brasil XI/74\ M. Alvarenga ” (DZUP); 1 ♂, “ Encruzilhada \ BA. Brasil XII./80\ M. Alvarenga ” (DZUP); Minas Gerais: 1 ♂, “ Brasil, Minas Gerais, 12km a N de\ Águas Vermelhas, Faz.\ Faceiro, 15.640ºS \ 41.477ºW, 845m,\ 12.xii.2012 G. Melo & P.\ Grossi. Arm luminosa” (DZUP); 1 ♀, “ Brasil, Minas Gerais, 22km \ a NE de Pedra Azul, 15.819ºS 41.200ºW, 745m,\ 13.xii.2012, G. Melo &\ P. Grossi ” (DZUP). Notes. Proxima meloi sp. nov. can be distinguished from other species of Proxima by its subgenital plate (Fig. 40) with inner margin strongly expanded medially and by the aedeagus (Fig. 43) with atrial processes simple and as long as shaft.

Proxima nigromaculata sp. nov. (Figs 13���32, 54, 55) Diagnosis. Forewing (Fig. 16) with pair of dark brown maculae at apical third. Male pygofer (Figs 19, 20) with apex folded inwardly. Subgenital plate (Fig. 21), in ventral view, with inner margin mostly straight. Style (Figs 22, 23), in lateral view, with blade sinuous and slender; ventral margin smooth. Aedeagus (Figs 24, 25) with atrial processes not bifid and not exceeding apex of shaft; apex bifid into filiform projections directed posteroventrally. Measurements (mm). 10.8���13.0 mm (male); 13.4���15.4 mm (female). Coloration. Color pattern as in generic description, except for two dark brown maculae on corium of the forewing, one at the base of the first apical cell and appendix, and the other at wing apex (Figs 16, 54, 55). External morphology. Forewing (Fig. 16) with or without few extra-numerary veins on apical half, frequently on subapical cells. Other characters as in generic description. Male terminalia. Sternite VIII (Fig. 17), in ventral view, subrectangular; approximately 1.3 times wider than long; lateral margins parallel; posterolateral angles rounded; posterior margin with a median lobe slightly emarginated medially. Valve (Fig. 18), in ventral view, approximately 2.4 times wider than long; anterior and posterior margins rectilinear. Pygofer (Fig. 19), in lateral view, approximately 2.3 times longer than high; inner surface of lateral lobe with a thickening of the integument at anterodorsal portion; ventral margin slightly rounded; posterior margin sinuous; apex rounded, folded inwardly (Fig. 20). Subgenital plate (Fig 21), in ventral view, 3.6 times longer than wide; ligulate; outer margin rectilinear; inner margin slightly rounded; apex widely rounded. Connective (Fig. 22), in dorsal view, with arms longer than stalk; anterior margin deeply excavated; stalk short and enlarged apically. Style (Fig. 22), in dorsal view, with lateral lobe slightly rounded; in lateral view (Fig. 23), with blade sinuous and slender, slightly narrowing towards apex; ventral margin smooth; apex strongly curved dorsally. Aedeagus (Figs 24, 25) with preatrium moderately developed; dorsal apodeme underdeveloped with dorsal margin straight, weakly projected laterally; atrial processes slightly sclerotized, short, not exceeding apex of shaft, expanded preapically and with apex acute and curved ventrally; shaft broad at base and narrowing towards the apex, flattened dorsoventrally at apical half; apex bifid into poorly sclerotized filiform projections directed posteroventrally. Female terminalia. Sternite VII (Fig. 26), in ventral view, approximately 1.3 times wider than long; lateral margins parallel; posterolateral angle subacute; posterior margin excavated near lateral angles, with distinct median lobe excavated medially. Pygofer (Fig. 27), in lateral view, approximately 1.4 times longer than high; macrosetae distributed at apical half and along ventral margin; apex slightly truncated. First valvifer (Fig. 28), in lateral view, subquadrangular, as high as long, posterior margin rounded. First valvula (Figs 28, 29), in lateral view, approximately 7.1 times longer than high; apex subacute. Second valvula (Figs 30, 31), in lateral view, approximately 11.2 times longer than high; dorsal margin with three teeth widely separated in the apical half, being the basal larger than others; apex rounded. Second valvifer (Fig. 32), in lateral view, approximately 2.2 times higher than wide. Gonoplac (Fig. 32), in lateral view, approximately 3.7 times longer than high. Other characters as in generic description. Etymology. The species epithet refers to the black maculae on the forewing. Material examined: Holotype male: ��� Brasil, Paran��, Tibagi \ P. E. do Guartel��, 1000m \ 24��33���47���S 50��15���26���W \ 21-24.XI.2016 Sweep \ A.C. Domahovski leg.��� (DZUP). Paratypes: Paran��: 1 ♂, 1 ♀, ��� Brasil, PR, Antonina \ Res. Rio Cachoeira \ 25,316��S 46.696��W \ 50m 20-25.xi.2014 \ Luminosa \ Entomologia UFPR ��� (DZUP); Esp��rito Santo: 2 ♂, ��� Brasil, ES, Domingos Martins,\ Cultivo soja, 20��22���17,3���S \ 41��03���47,7���W, 950 m,\ 30.XI.2016, J. S. Zanuncio \ Junior leg.��� (DZUP); Maranh��o: 1 ♀, ��� Brasil, MA, Caxias,\ Povoado do Ouro Light\ trap 01.ii.2014 Grossi &\ Pinto Jr. Legs. ��� ��� DZRJ-AUCH \ 0230���(DZRJ); Minas Gerais: 1 ♂, 1 ♀, ���Serra do Cara��a\ MG Brasil \ 27.XI a 5.XII.1972 \ Exp. Mus. Zool.��� (MZSP); Rio de Janeiro: 1 ♂, ��� Brasil, Rio de Janeiro, P.N. de\ Itatiaia, Quiosque do po��o\ azul, 22��27���07���S,\ 44��36���45���W, 17-18.xi.2012,\ D.M.Takiya & A.P.M.Santos ��� ���DNA voucher\ Entomologia, DZRJ \ ENT 1292 ��� ��� DZRJ-AUCH \ 0229���(DZRJ); 1 ♂, ��� Brasil, RJ, Nova Friburgo\ Sans Sousi\ 20.XII.2008 - 15.I.2009 \ P. Grossi leg. Luz ��� ��� DZRJ-AUCH \ 0231���(DZRJ); Rio Grande do Sul: 1 ♂, ��� Brasil, RS, Passo Fundo,\ M. Atl��ntica, 28��13���50.7���S \ 52��24���17,04���W, 671 m,\ 24.III.2017, P. R. V. \ da Silva Pereira leg.��� (DZUP). Notes. Proxima nigromaculata sp. nov. differs from other species of the genus by its forewing (Fig. 16) with a pair of dark maculae at apical third, male pygofer (Fig. 19) with apex folded inwardly, and aedeagus (Fig. 24) with atrial processes poorly sclerotized and distinctly shorter than shaft., Published as part of Laranjeira, Vanessa Cristina, Gon��alves, Clayton Corr��a, Domahovski, Alexandre Cruz & Takiya, Daniela Maeda, 2022, Review of Proxima DeLong & Freytag (Hemiptera: Cicadellidae: Gyponini) with description of two new species from Brazil and identification key to species, pp. 573-586 in Zootaxa 5091 (4) on pages 577-580, DOI: 10.11646/zootaxa.5091.4.5, http://zenodo.org/record/5864234

Proxima ocellata DeLong & Freytag, 1975 (Figs 1���12, 52, 53) Proxima ocellata DeLong & Freytag, 1975: 111. Diagnosis. Forewing (Fig. 4) without dark maculae. Male pygofer (Fig. 7), in lateral view, with apical portion curved dorsally. Subgenital plate (Fig. 8), in ventral view, with inner margin slightly convex. Style (Fig. 10), in lateral view, with ventral margin excavated at median third and serrated. Aedeagus (Figs 11, 12) with atrial processes bifid apically; shaft with pair of lateral bifid subapical processes; apex bifid, forming short spatulate processes. Measurements (mm). 8.8 (male). Coloration. Color pattern as in generic description. External morphology. Forewing (Fig. 4) without extra-numerary veins. Other characters as in generic description. Male terminalia. Sternite VIII (Fig. 5), in ventral view, subrectangular; approximately 1.4 times wider than long; lateral margins rectilinear; posterolateral angles rounded; posterior margin with a small median lobe, slightly emarginated medially. Valve (Fig. 6), in ventral view, approximately 2.5 times wider than long; posterior margin slightly excavated medially. Pygofer (Fig. 7), in lateral view, with ventral margin broadly rounded; posterior margin oblique; apex subacute, curved dorsally. Subgenital plate (Fig. 8), in ventral view, 3.5 times longer than wide; ligulate; outer lateral margin slightly excavated medially; inner lateral margin widely rounded; apex rounded. Connective (Fig. 9), in dorsal view, with robust arms slightly longer than stalk; anterior margin slightly excavated; stalk short and expanded apically. Style (Fig. 9), in dorsal view, with truncated lateral lobe; in lateral view (Fig. 10), with high blade for almost entire length, abruptly narrowing apically; ventral margin serrated, excavated at median third; apex acute and curved dorsally. Aedeagus (Figs 11, 12) with preatrium short; dorsal apodeme poorly developed, with dorsal margin rounded, not expanded laterally; pair of atrial processes strongly expanded medially, ventral margin with tooth at median third, apical third bifid, forming a dorsal branch with approximately twice the length of the ventral branch, both acute and direct anteriorly; shaft long, slender and subtubular, slightly flattened laterally, with pair of lateral, short and bifid subapical processes, ventral branch about twice longer and thicker than dorsal branch; apex bifid, forming short spatulate processes, poorly sclerotized. Female unknown. Material examined. Minas Gerais: 1 ♂, ��� Brasil, Minas Gerais,\ Itabirito, Vale dos Tropeiros, Cachoeira das Carrancas,\ 10.x.2010, 20��12���28.3���S,\ 43��38���26���W, 1046m, L.\ Dumas & N. Ferreira Jr. ���, ���DNA voucher\ Entomologia, DZRJ \ ENT 1313 ��� ��� DZRJ- AUCH \ 0228��� (DZRJ). Notes. Proxima ocellata can be easily distinguished from other species of the genus by its aedeagus with bifid atrial processes (Fig. 11).Although in this study, the holotype was not studied, there is no doubt about the identification of the specimen redescribed here, which agrees completely with the original description and illustrations (DeLong & Freytag, 1975)., Published as part of Laranjeira, Vanessa Cristina, Gon��alves, Clayton Corr��a, Domahovski, Alexandre Cruz & Takiya, Daniela Maeda, 2022, Review of Proxima DeLong & Freytag (Hemiptera: Cicadellidae: Gyponini) with description of two new species from Brazil and identification key to species, pp. 573-586 in Zootaxa 5091 (4) on pages 575-577, DOI: 10.11646/zootaxa.5091.4.5, http://zenodo.org/record/5864234, {"references":["DeLong, D. M. & Freytag, P. H. (1975) Two new genera, Proxima and Angucephala and two new species of Gyponinae (Homoptera: Cicadellidae). Journal of the Kansas Entomological Society, 48 (1), 110 - 113."]}

The discovery of Proxima b marked one of the most important milestones in exoplanetary science in recent years. Yet the limited precision of the available radial velocity data and the difficulty in modelling the stellar activity calls for a confirmation of the Earth-mass planet. We aim to confirm the presence of Proxima b using independent measurements obtained with the new ESPRESSO spectrograph, and refine the planetary parameters taking advantage of its improved precision. Methods: We analysed 63 spectroscopic ESPRESSO observations of Proxima (Gl 551) taken during 2019. We obtained radial velocity measurements with a typical radial velocity photon noise of 26 cm s-1. We combined these data with archival spectroscopic observations and newly obtained photometric measurements to model the stellar activity signals and disentangle them from planetary signals in the radial velocity (RV) data. We ran a joint Markov chain Monte Carlo analysis on the time series of the RV and full width half maximum of the cross-correlation function to model the planetary and stellar signals present in the data, applying Gaussian process regression to deal with the stellar activity signals. We confirm the presence of Proxima b independently in the ESPRESSO data and in the combined ESPRESSO+ HARPS+UVES dataset. The ESPRESSO data on its own shows Proxima b at a period of 11.218 ± 0.029 days, with a minimum mass of 1.29 ± 0.13 M⊕. In the combined dataset we measure a period of 11.18427 ± 0.00070 days with a minimum mass of 1.173 ± 0.086 M⊕. We get a clear measurement of the stellar rotation period (87 ± 12 d) and its induced RV signal, but no evidence of stellar activity as a potential cause for the 11.2 days signal. We find some evidence for the presence of a second short-period signal, at 5.15 days with a semi-amplitude of only 40 cm s-1. If caused by a planetary companion, it would correspond to a minimum mass of 0.29 ± 0.08 M⊕. We find that forthe case of Proxima, the full width half maximum of the cross-correlation function can be used as a proxy for the brightness changes and that its gradient with time can be used to successfully detrend the RV data from part of the influence of stellar activity. The activity-induced RV signal in the ESPRESSO data shows a trend in amplitude towards redder wavelengths. Velocities measured using the red end of the spectrograph are less affected by activity, suggesting that the stellar activity is spot dominated. This could be used to create differential RVs that are activity dominated and can be used to disentangle activity-induced and planetary-induced signals. The data collected excludes the presence of extra companions with masses above 0.6 M⊕ at periods shorter than 50 days., Seminar at the University of Birmingham

Bachelor thesis focuses on the analysis of the technical parameters of transmissions for tractors. The introductory part of this work deals generally with transmission devices as such and their related systems. It will be pointed to the importance of selecting the correct transmission device for a given application, as well as to the importance of this device properly construct and dimension. Next there is discussed the basic structural design of transmissions and will put their advantages and disadvantages, along with an explanation of the structure and principle of operation of these systems. Furthermore, this work deals with the parameters used for calculating technical parameters transmissions. And lastly, they will be compared to the selected solutions of different transmissions from different manufacturers. At the conclusion of this work are summarized findings from previous points.

The use of increasingly complex hardware and software platforms in response to the ever rising performance demands of modern real-time systems complicates the verification and validation of their timing behaviour, which form a time-and-effort-intensive step of system qualification or certification. In this paper we relate the current state of practice in measurement-based timing analysis, the predominant choice for industrial developers, to the proceedings of the PROXIMA (Probabilistic real-time control of mixed-criticality multicore systems) project in that very field. We recall the difficulties that the shift towards more complex computing platforms causes in that regard. Then we discuss the probabilistic approach proposed by PROXIMA to overcome some of those limitations. We present the main principles behind the PROXIMA approach as well as the changes it requires at hardware or software level underneath the application. We also present the current status of the project against its overall goals, and highlight some of the principal confidence-building results achieved so far. The research leading to these results has received funding from the European Community’s Seventh Framework Programme [FP7/2007-2013] under the PROXIMA Project (grant agreement 611085). Carles Hern´andez is jointly funded by the Spanish Ministry of Economy and Competitiveness (MINECO) and FEDER funds through grant TIN2014-60404-JIN. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717.

En aquest projecte es definirà una metodologia per al desenvolupament de manera sistemàtica de nano i picosatèl·lits, definint els standards per a optimizar els dissenys, minimitzant components, transcicions, alimentacions, facilitant la integració, la interconnexió i interoperabilitat amb d'altres subsistemas desenvolupats per terceres parts. The vision of the NanoSat Lab of the Universitat Politècnica de Catalunya (UPC BarcelonaTech) is the exploration and development of innovative applications and remote sensing techniques based on standard nano-satellite platforms (e.g. CubeSats). At the same time, we aim at developing our own platforms, while complying with the CubeSat standard. From the experience gained in our firsts two missions (3Cat-1 and 3Cat-2, to be launched in July 2016), the NanoSat Lab is now continuing its labour keeping an eye on the developing new and innovative hardware for the next generation of CubeSat missions. In this approach, the purpose of this project is to propose a first version of a new CubeSat standard and lay the groundwork for the development of a future multi-purpose hardware platform able to perform generic LEO missions or other technology demonstrations. La visión del NanoSat Lab de la Universitat Politècnia de Catalunya (UPC – BarcelonaTech) es la exploración y el desarrollo de innovadoras aplicaciones y técnicas para la observación de la Tierra basadas en plataformas de nano-satélites estandarizadas (por ejemplo: CubeSats) así como el desarrollo de dichas plataformas. DE la experiencia ganada a partir de nuestras dos primeras misiones (3Cat-1 i 3Cat-2), que se lanzarán en Julio de 2016, en NanoSat Lab continúa ahora su labor con la mirada puesta en el desarrollo de un nuevo e innovador hardware para la próxima generación de misiones CubeSat. En este enfoque, el propósito de este trabajo es proponer una primera versión de un nuevo y actualizado standard de CubeSat y asentar las bases para el desarrollo de una futura plataforma hardware capacitada para llevar a cabo misiones genéricas basadas en CubeSats en órbita baja. La visió del NanoSat Lab de la Universitat Politècnica de Catalunya (UPC BarcelonaTech) és la exploració i el desenvolupament de innovadores aplicacions i tècniques per a la observació de la Terra basades en plataformes de nano-satèl·lits estandarditzades (per exemple: CubeSats) així com el desenvolupament de les citades plataformes. De la experiència guanyada a partir de les nostres dues primeres missions (3Cat-1 i 3Cat-2, que es llençaran al Juliol de 2016), el NanoSat Lab continua ara la seva labor amb la mirada posada en el desenvolupament de nou i innovador hardware per a la propera generació de missions CubeSat. En aquest enfocament, el propòsit d’aquest treball es proposar la primera versió d’un nou i actualitzat standard CubeSat i assentar les bases per al desenvolupament d’una futura plataforma hardware capacitada per a dur a terme missions genèriques basades en CubeSats en òrbita baixa.

An illustrated glossary of terms used in the analysis of the shells of recent and fossil foraminifera supplemented by a rigorous selection of terms that facilitate an understanding of their biology and their use in ecology and biostratigraphy. The glossary includes some 650 entries illustrated by 83 - often composite – figures many of which are stereographs or 3D models. A taxonomic index lists the 140 taxa illustrated.