Pengaruh Penggantian Sebagian Agregat Halus Dengan Kertas Koran Bekas Pada Campuran Batako Semen Portland Terhadap Kuat Tekan Dan Serapan Air

Ketersedian material alam untuk konstruksi sangatlah terbatas, di lain pihak permintaan akanmaterial tersebut terus meningkat, sehingga perlu dicoba untuk menggunakan materialalternatif seperti memanfaatkan barang bekas yang sering menjadi sampah sebagai materialkonstruksi. Salah satu alternatif yang dicoba adalah kertas koran bekas sebagai materialtambahan dalam campuran batako semen portland untuk menggantikan sebagian pasir,sehingga dapat mengurangi pemakaian pasir dan diharapkan dapat mengurangi sampah sertadiperoleh batako semen portland yang memiliki bobot lebih ringan. Penelitian dilakukandengan membuat batako semen portland berlubang (hollow block) berdimensi 40 x 20 x 10cm yang terdiri dari batako semen portland normal (tanpa penggantian pasir dengan kertaskoran) dan batako semen portland dengan penggantian pasir dengan kertas koran masingmasingsebanyak 15%, 20%, 25% dan 30% volume pasir. Hasil penelitian menunjukanbahwa penambahan kertas koran bekas dalam campuran batako semen portland untukmenggantikan sebagian pasir mengakibatkan penurunan nilai kuat tekan dan peningkatannilai penyerapan air (absorpsi). Kuat tekan batako semen portland normal pada umur 28 hariadalah sebesar 6,71 MPa, nilai ini menurun menjadi berturut-turut sebesar 6,51 MPa, 5,90MPa, 5,08 MPa dan 4,51 MPa pada penambahan kertas koran sebesar 15%, 20%, 25% dan30% volume pasir sedangkan absorpsinya masing masing 8,43%, 8,72%, 9,18% dan 10,36%pada penambahan kertas koran berturut-turut sebesar 15%, 20%, 25% dan 30% volume pasir,lebih tinggi dari batako tanpa penambahan kertas yaitu 6.53

Manifestações neuropsiquiátricas do hiperparatiroidismo primário no idoso: relato de casos e revisão da literatura

Osteoporosis and neuropsychiatric disorders occur more frequently in elderly than in young people. When they appear together there is a possibility of a common etiology. We report two cases of elderly women at the ages of 75 and 80y with established osteoporosis and neuropsychiatric manifestations (apathy, weakness, depression and loss of memory) caused by hypercalcemia (ionic calcium of 1.43mmol/L and 1.65mmol/L, respectively) due to primary hyperparathyroidism (PHPT). Other laboratory results showed normal levels of the intact fraction of parathormone (iPTH), i.e. 64 and 63pg/ml, respectively. They were submitted to parathyroidectomy and only one tumoral mass was removed from each woman. Pathologic examination showed parathyroid adenoma. Shortly after the surgery they got better of the neuropsychiatric signs and symptoms. Six months later the bone mineral density (BMD) of the second patient increased whereas the other one was unable to have her BMD evaluated due to thoracic deformities. The possibility of PHPT must be always considered, especially in patients with normal but not suppresible parathormone levels. The reason is that some parathyroid adenomas present an abnormal set point to calcium and no significantly increase in parathormone production. It should be emphasized that there is no satisfactory medical treatment for parathyroid adenoma except for surgical excision, which is effective in the majority of cases. We conclude that ionic calcium must be measured in all elderly patients who present neuropsychiatric disorders and/ or osteoporosis.A osteoporose e os distúrbios neuropsiquiátricos surgem com maior freqüência entre os pacientes idosos, quando comparados com as demais faixas etárias. Manifestações concomitantes destas síndromes podem apresentar causas comuns. Neste artigo, nós descrevemos os casos de duas mulheres com osteoporose estabelecida e idades de 75 e 80 anos, que desenvolveram sinais e sintomas neuropsiquiátricos (apatia, fraqueza, depressão e perda de memória) associados a hipercalcemia [cálcio iônico de 1,43mmol/L e 1,65mmol/L (1,14 - 1,30mmol/L), respectivamente]. Na investigação laboratorial foi observado que os níveis da fração intacta do paratormônio (PTHi) estavam dentro dos limites da normalidade (64 e 63pg/ml, respectivamente) ou não suprimidos. Após exploração cirúrgica cervical foram removidas, de cada paciente, massas tumorais únicas, cujo anátomo-patológico revelou adenoma de paratireóide. As duas pacientes apresentaram melhora dos sintomas e sinais neuropsiquiátricos após a cirurgia e a segunda paciente obteve ganho de massa óssea significativo, sem uso de qualquer droga anti-reabsortiva. A outra paciente não pode ser avaliada através da densitometria óssea, devido às deformidades na coluna torácica. A possibilidade de HPTP deve ser sempre considerada, principalmente em pacientes com níveis de paratormônio dentro da faixa de normalidade, ou não suprimidos apesar de cálcio ionizado elevado. Isso ocorre devido a alguns tumores de paratireóide apresentarem set point alterado em relação aos níveis de cálcio mas sem aumento significativo da produção de paratormônio. Outra correlação observada é que quanto menor forem os adenomas, maior a chance de serem hipersecretores e autônomos. Em conclusão, a aferição do cálcio iônico em pacientes idosos com osteoporose e ou sintomas e sinais neuropsiquiátricos deve ser feita de rotina com o objetivo de se excluir doenças que possam ser tratadas prontamente e com bons resultados.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de MedicinaUNIFESP, EPM, Depto. de MedicinaSciEL

A workforce survey of Australian chiropractic: The profile and practice features of a nationally representative sample of 2,005 chiropractors

© 2017 The Author(s). Background: This paper reports the profile of the Australian chiropractic workforce and characteristics of chiropractic care from a large nationally-representative sample of practitioners. Methods: A 21-item questionnaire examining practitioner, practice and clinical management characteristics was distributed to all registered chiropractors (n=4,684) in Australia in 2015 via both online and hard copy mail out. Results: The survey attracted a response rate of 43% (n=2,005), and the sample is largely representative of the national chiropractic workforce on a number of key indicators. The average age of the chiropractors was 42.1 years, nearly two-thirds are male, and the vast majority hold a bachelor degree or higher qualification. Australian chiropractors are focused upon treating people across a wide age range who mainly present with musculoskeletal conditions. Australian chiropractors have referral relationships with a range of conventional, allied health and complementary medicine (CAM) providers. Conclusion: The chiropractic profession represents a substantial component of the contemporary Australian health care system with chiropractors managing an estimated 21.3 million patient visits per year. While the Australian chiropractic workforce is well educated, research engagement and research capacity remains sub-optimal and there is much room for further capacity building to help chiropractic reach full potential as a key integrated profession within an evidence-based health care system. Further rich, in-depth research is warranted to improve our understanding of the role of chiropractic within the Australian health care system

Localized starbursts in dwarf galaxies produced by impact of low metallicity cosmic gas clouds

Models of galaxy formation predict that gas accretion from the cosmic web is a primary driver of star formation over cosmic history. Except in very dense environments where galaxy mergers are also important, model galaxies feed from cold streams of gas from the web that penetrate their dark matter haloes. Although these predictions are unambiguous, the observational support has been indirect so far. Here we report spectroscopic evidence for this process in extremely metal-poor galaxies (XMPs) of the local Universe, taking the form of localized starbursts associated with gas having low metallicity. Detailed abundance analyses based on Gran Telescopio Canarias (GTC) optical spectra of ten XMPs show that the galaxy hosts have metallicities around 60 % solar on average, while the large star-forming regions that dominate their integrated light have low metallicities of some 6 % solar. Because gas mixes azimuthally in a rotation timescale (a few hundred Myr), the observed metallicity inhomogeneities are only possible if the metal-poor gas fell onto the disk recently. We analyze several possibilities for the origin of the metal-poor gas, favoring the metal-poor gas infall predicted by numerical models. If this interpretation is correct, XMPs trace the cosmic web gas in their surroundings, making them probes to examine its properties.Comment: Accepted for publication in ApJ

Spectroscopy of superluminous supernova host galaxies. A preference of hydrogen-poor events for extreme emission line galaxies

Superluminous supernovae (SLSNe) are very bright explosions that were only discovered recently and that show a preference for occurring in faint dwarf galaxies. Understanding why stellar evolution yields different types of stellar explosions in these environments is fundamental in order to both uncover the elusive progenitors of SLSNe and to study star formation in dwarf galaxies. In this paper, we present the first results of our project to study SUperluminous Supernova Host galaxIES, focusing on the sample for which we have obtained spectroscopy. We show that SLSNe-I and SLSNe-R (hydrogen-poor) often (~50% in our sample) occur in a class of galaxies that is known as Extreme Emission Line Galaxies (EELGs). The probability of this happening by chance is negligible and we therefore conclude that the extreme environmental conditions and the SLSN phenomenon are related. In contrast, SLSNe-II (hydrogen-rich) occur in more massive, more metal-rich galaxies with softer radiation fields. Therefore, if SLSNe-II constitute a uniform class, their progenitor systems are likely different from those of H-poor SLSNe. Gamma-ray bursts (GRBs) are, on average, not found in as extreme environments as H-poor SLSNe. We propose that H-poor SLSNe result from the very first stars exploding in a starburst, even earlier than GRBs. This might indicate a bottom-light initial mass function in these systems. SLSNe present a novel method of selecting candidate EELGs independent of their luminosity.Comment: Published version, matches proofs. Accepted 2015 February 13. 23 pages, 8 figures, 4 tables. Minor changes with respect to previous versio

Identification of z~>2 Herschel 500 micron sources using color-deconfusion

We present a new method to search for candidate z~>2 Herschel 500{\mu}m sources in the GOODS-North field, using a S500{\mu}m/S24{\mu}m "color deconfusion" technique. Potential high-z sources are selected against low-redshift ones from their large 500{\mu}m to 24{\mu}m flux density ratios. By effectively reducing the contribution from low-redshift populations to the observed 500{\mu}m emission, we are able to identify counterparts to high-z 500{\mu}m sources whose 24{\mu}m fluxes are relatively faint. The recovery of known z~4 starbursts confirms the efficiency of this approach in selecting high-z Herschel sources. The resulting sample consists of 34 dusty star-forming galaxies at z~>2. The inferred infrared luminosities are in the range 1.5x10^12-1.8x10^13 Lsun, corresponding to dust-obscured star formation rates (SFRs) of ~260-3100 Msun/yr for a Salpeter IMF. Comparison with previous SCUBA 850{\mu}m-selected galaxy samples shows that our method is more efficient at selecting high-z dusty galaxies with a median redshift of z=3.07+/-0.83 and 10 of the sources at z~>4. We find that at a fixed luminosity, the dust temperature is ~5K cooler than that expected from the Td-LIR relation at z<1, though different temperature selection effects should be taken into account. The radio-detected subsample (excluding three strong AGN) follows the far-infrared/radio correlation at lower redshifts, and no evolution with redshift is observed out to z~5, suggesting that the far-infrared emission is star formation dominated. The contribution of the high-z Herschel 500{\mu}m sources to the cosmic SFR density is comparable to that of SMG populations at z~2.5 and at least 40% of the extinction-corrected UV samples at z~4 (abridged).Comment: 33 pages in emulateapj format, 24 figures, 2 tables, accepted for publication in the ApJ

Spectrophotometric investigations of Blue Compact Dwarf Galaxies: Markarian 35

We present results from a detailed spectrophotometric analysis of the blue compact dwarf galaxy Mrk 35 (Haro 3), based on deep optical (B,V,R,I) and near-IR (J,H,K) imaging, Halpha narrow-band observations and long-slit spectroscopy. The optical emission of the galaxy is dominated by a central young starburst, with a bar-like shape, while an underlying component of stars, with elliptical isophotes and red colors, extends more than 4 kpc from the galaxy center. High resolution Halpha and color maps allow us to identify the star-forming regions, to spatially discriminate them from the older stars, and to recognize several dust patches. We derive colors and Halpha parameters for all the identified star-forming knots. Observables derived for each knot are corrected for the contribution of the underlying older stellar population, the contribution by emission lines, and from interstellar extinction, and compared with evolutionary synthesis models. We find that the contributions of these three factors are by no means negligible and that they significantly vary across the galaxy. Therefore, careful quantification and subtraction of emission lines, galaxy host contribution, and interstellar reddening at every galaxy position, are essential to derive the properties of the young stars in BCDs. We find that we can reproduce the colors of all the knots with an instantaneous burst of star formation and the Salpeter initial mass function with an upper mass limit of 100 M_solar. In all cases the knots are just a few Myr old. The underlying population of stars has colors consistent with being several Gyr old.Comment: 21 pages, 13 figures. Accepted for publication in ApJ, tentatively scheduled for the ApJ November 1, 2007 v669n1 issu

Optical Line Emission from z∼\sim6.8 Sources with Deep Constraints on Lyα\alpha Visibility

We analyze a sample of $z$-dropout galaxies in the CANDELS GOODS South and UDS fields that have been targeted by a dedicated spectroscopic campaign aimed at detecting their Ly$\alpha$ line. Deep IRAC observations at 3.6 and 4.5 $\mu$m are used to determine the strength of optical emission lines affecting these bands at z$\sim$6.5-6.9 in order to i) investigate possible physical differences between Ly$\alpha$ emitting and non-emitting sources; ii) constrain the escape fraction of ionizing photons; iii) provide an estimate of the specific star-formation rate at high redshifts. We find evidence of strong [OIII]+H$\beta$ emission in the average (stacked) SEDs of galaxies both with and without Ly$\alpha$ emission. The blue IRAC [3.6]-[4.5] color of the stack with detected Ly$\alpha$ line can be converted into a rest-frame equivalent width EW([OIII]+H$\beta$)=1500$^{+530}_{-440}\AA$ assuming a flat intrinsic stellar continuum. This strong optical line emission enables a first estimate of f$_{esc}\lesssim$20% on the escape fraction of ionizing photons from Ly$\alpha$ detected objects. The objects with no Ly$\alpha$ line show less extreme EW([OIII]+H$\beta$)=520$^{+170}_{-150}\AA$ suggesting different physical conditions of the HII regions with respect to Ly$\alpha$-emitting ones, or a larger f$_{esc}$. The latter case is consistent with a combined evolution of f$_{esc}$ and the neutral hydrogen fraction as an explanation of the lack of bright Ly$\alpha$ emission at z$>$6. A lower limit on the specific star formation rate, SSFR$>$9.1$Gyr^{-1}$ for $M_{star}=2 \times 10^9 M_{\odot}$ galaxies at these redshifts can be derived from the spectroscopically confirmed sample.Comment: 10 pages, 7 figures; The Astrophysical Journal in press; matched to the published versio

Limits on the LyC signal from z~3 sources with secure redshift and HST coverage in the E-CDFS field

Aim: We aim to measure the LyC signal from a sample of sources in the Chandra deep field south. We collect star-forming galaxies (SFGs) and active galactic nuclei (AGN) with accurate spectroscopic redshifts, for which Hubble Space Telescope (HST) coverage and multi-wavelength photometry are available. Method: We selected a sample of about 200 sources at z~3. Taking advantage of HST resolution, we applied a careful cleaning procedure and rejected sources showing nearby clumps with different colours, which could be lower-z interlopers. Our clean sample consisted of 86 SFGs (including 19 narrow-band selected Lya emitters) and 8 AGN (including 6 detected in X-rays). We measured the LyC flux from aperture photometry in four narrow-band filters covering wavelengths below a 912 A rest frame (3.11<z<3.53). We estimated the ratio between ionizing (LyC flux) and 1400 A non-ionizing emissions for AGN and galaxies. Results: By running population synthesis models, we assume an average intrinsic L(1400 A)/L(900 A) ratio of 5 as the representative value for our sample. With this value and an average treatment of the lines of sight of the inter-galactic medium, we estimate the LyC escape fraction relative to the intrinsic value (fesc_rel(LyC)). We do not directly detect ionizing radiation from any individual SFG, but we are able to set a 1(2)sigma upper limit of fesc_rel(LyC)<12(24)%. This result is consistent with other non-detections published in the literature. No meaningful limits can be calculated for the sub-sample of Lya emitters. We obtain one significant direct detection for an AGN at z=3.46, with fesc_rel(LyC) = (72+/-18)%. Conclusions: Our upper limit on fescrel(LyC) implies that the SFGs studied here do not present either the physical properties or the geometric conditions suitable for efficient LyC-photon escape.Comment: Accepted for publication in A&A on Jan 5th, 201

Nuclear Saturation with in-Medium Meson Exchange Interactions

We show that the assumption of dropping meson masses together with conventional many-body effects, implemented in the relativistic Dirac-Brueckner formalism, explains nuclear saturation. We use a microscopic model for correlated $2\pi$ exchange and include the standard many-body effects on the in-medium pion propagation, which initially increase the attractive nucleon-nucleon ($NN$) potential with density. For the vector meson exchanges in both the $\pi\pi$ and $NN$ sector, we assume Brown-Rho scaling which---in concert with `chiral' $\pi\pi$ contact interactions---reduces the attraction at higher densities.Comment: 5 pages REVTeX, 2 eps-figures included, submitted to Phys. Rev. Let