232 research outputs found
Dukungan Berbagai Pihak dan Pengetahuan terhadap Perilaku Remaja dalam Pencegahan Kehamilan Tidak Diinginkan di SMK 9 Bandung
Penetapan Kadar Tanin Dalam Infusa Daun Salam (Syzygium Polyanthum (Wight.) Walp)) Secara Spektrofotometri Sinar Tampak
People used many traditional medicinal plants. One of them is leaf of salam (Syzygium polyanthum (Wight.) Walp). One of its active compound is tannin that used to treat diarrhoae. The aim of this research was to determine tannin content of salam leaves from different age. Sample that used in this research were young and old salam leaves. Infundation method was used to extract tannin from salam leaves. Tannin content of the infusion was determined by ultraviole-visible spectrophotometry with addition of Folin Denis reagent. Maximum wavelength was 745.0 nm. The result of tannin content in young and old salam leaves were 0.036±1.513% and 7.07x10-3±0.288% respectively. t test showed that there were differences of tannin content in young and old salam leaves.
Keywords: tannin, salam leaf, infusion, ultraviolet-visible spectrophotometr
Extended Gaussian wave packet dynamics
We examine an extension to the theory of Gaussian wave packet dynamics in a
one-dimensional potential by means of a sequence of time dependent displacement
and squeezing transformations. Exact expressions for the quantum dynamics are
found, and relationships are explored between the squeezed system, Gaussian
wave packet dynamics, the time dependent harmonic oscillator, and wave packet
dynamics in a Gauss-Hermite basis. Expressions are given for the matrix
elements of the potential in some simple cases. Several examples are given,
including the propagation of a non-Gaussian initial state in a Morse potential
Fluid shear stress modulation of hepatocyte like cell function
Freshly isolated human adult hepatocytes are considered to be the gold standard tool for in vitro studies. However, primary hepatocyte scarcity, cell cycle arrest and the rapid loss of cell phenotype limit their widespread deployment. Human embryonic stem cells and induced pluripotent stem cells provide renewable sources of hepatocyte-like cells (HLCs). Despite the use of various differentiation methodologies, HLCs like primary human hepatocytes exhibit unstable phenotype in culture. It has been shown that the functional capacity can be improved by adding back elements of human physiology, such as cell co-culture or through the use of natural and/or synthetic surfaces. In this study, the effect of fluid shear stress on HLC performance was investigated. We studied two important liver functions, cytochrome P450 drug metabolism and serum protein secretion, in static cultures and those exposed to fluid shear stress. Our study demonstrates that fluid shear stress improved Cyp1A2 activity by approximately fivefold. This was paralleled by an approximate ninefold increase in sensitivity to a drug, primarily metabolised by Cyp2D6. In addition to metabolic capacity, fluid shear stress also improved hepatocyte phenotype with an approximate fourfold reduction in the secretion of a foetal marker, alpha-fetoprotein. We believe these studies highlight the importance of introducing physiologic cues in cell-based models to improve somatic cell phenotype
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The GAPS Programme at TNG XXXVII. A precise density measurement of the young ultra-short period planet TOI-1807 b
Context. Great strides have been made in recent years in the understanding of the mechanisms involved in the formation and evolution of planetary systems. Despite this, many observational findings have not yet been corroborated by astrophysical explanations. A fine contribution to the study of planetary formation processes comes from the study of young, low-mass planets, with short orbital periods (.100 days). In the last three years, the NASA/TESS satellite has identified many planets of this kind and their characterization is clearly necessary in order to understand how they formed and evolved. Aims. Within the framework of the Global Architecture of Planetary System (GAPS) project, we performed a validation and characterization (radius and mass) of the ultra-short period planet TOI-1807 b, which orbits its young host star BD+39 2643 (âŒ300 Myr) in only 13 h. This is the youngest ultra-short period planet discovered so far. Methods. Thanks to a joint modeling of the stellar activity and planetary signals in the TESS light curve and in new HARPS-N radial-velocity measurements, combined with accurate estimation of stellar parameters, we validated the planetary nature of TOI-1807 b and measured its orbital and physical parameters. Results. By using astrometric, photometric, and spectroscopic observations, we found that BD+39 2643 is a young, active K dwarf star and a member of a 300 ± 80 Myr old moving group. Furthermore, it rotates in Prot = 8.8 ± 0.1 days. This star hosts an ultra-short period planet, exhibiting an orbital period of only Pb = 0.54937 ± 0.00001 days. Thanks to the exquisite photometric and spectroscopic series, along with the accurate information on its stellar activity, we measured both the radius and the mass of TOI-1807 b with high precision, obtaining RP,b = 1.37 ± 0.09 Râ and MP,b = 2.57 ± 0.50 Mâ. These planet parameters correspond to a rocky planet with an Earth-like density (Ïb = 1.0 ± 0.3 Ïâ) and no extended H/He envelope. From the analysis of the age-RP distribution for planets with well measured ages, we inferred that TOI-1807 b may have already lost a large part of its atmosphere over the course of its 300 Myr lifetime
Validating AU Microscopii d with Transit Timing Variations
AU Mic is a young (22 Myr) nearby exoplanetary system that exhibits excess
TTVs that cannot be accounted for by the two known transiting planets nor
stellar activity. We present the statistical "validation" of the tentative
planet AU Mic d (even though there are examples of "confirmed" planets with
ambiguous orbital periods). We add 18 new transits and nine midpoint times in
an updated TTV analysis to prior work. We perform the joint modeling of transit
light curves using EXOFASTv2 and extract the transit midpoint times. Next, we
construct an O-C diagram and use Exo-Striker to model the TTVs. We generate TTV
log-likelihood periodograms to explore possible solutions for the period of
planet d and then follow those up with detailed TTV and RV MCMC modeling and
stability tests. We find several candidate periods for AU Mic d, all of which
are near resonances with AU Mic b and c of varying order. Based on our model
comparisons, the most-favored orbital period of AU Mic d is 12.73596+/-0.00793
days (T_{C,d}=2458340.55781+/-0.11641 BJD), which puts the three planets near a
4:6:9 mean-motion orbital resonance. The mass for d is 1.053+/-0.511 M_E,
making this planet Earth-like in mass. If confirmed, AU Mic d would be the
first known Earth-mass planet orbiting a young star and would provide a
valuable opportunity in probing a young terrestrial planet's atmosphere.
Additional TTV observation of the AU Mic system are needed to further constrain
the planetary masses, search for possible transits of AU Mic d, and detect
possible additional planets beyond AU Mic c.Comment: 89 pages, 35 figures, 34 tables. Redid EXOFASTv2 transit modeling to
recover more reasonable stellar posteriors, so redid Exo-Striker TTV modeling
for consistency. Despite these changes, the overall results remain unchanged:
the 12-7-day case is still the most favored. Submitted to AAS Journals on
2023 Feb 9t
Validating AU Microscopii d with Transit Timing Variations
AU Mic is a young (22 Myr), nearby exoplanetary system that exhibits excess transit timing variations (TTVs) that cannot be accounted for by the two known transiting planets nor stellar activity. We present the statistical âvalidationâ of the tentative planet AU Mic d (even though there are examples of âconfirmedâ planets with ambiguous orbital periods). We add 18 new transits and nine midpoint times in an updated TTV analysis to prior work. We perform the joint modeling of transit light curves using EXOFASTv2 and extract the transit midpoint times. Next, we construct an O â C diagram and use Exo-Striker to model the TTVs. We generate TTV log-likelihood periodograms to explore possible solutions for dâs period, then follow those up with detailed TTV and radial velocity Markov Chain Monte Carlo modeling and stability tests. We find several candidate periods for AU Mic d, all of which are near resonances with AU Mic b and c of varying order. Based on our model comparisons, the most-favored orbital period of AU Mic d is 12.73596 ± 0.00793 days ( T _C _,d = 2458340.55781 ± 0.11641 BJD), which puts the three planets near 4:6:9 mean-motion resonance. The mass for d is 1.053 ± 0.511 M _â , making this planet Earth-like in mass. If confirmed, AU Mic d would be the first known Earth-mass planet orbiting a young star and would provide a valuable opportunity in probing a young terrestrial planetâs atmosphere. Additional TTV observations of the AU Mic system are needed to further constrain the planetary masses, search for possible transits of AU Mic d, and detect possible additional planets beyond AU Mic c
TOI-1416: A system with a super-Earth planet with a 1.07d period
TOI 1416 (BD+42 2504, HIP 70705) is a V=10 late G or early K-type dwarf star
with transits detected by TESS. Radial velocities verify the presence of the
transiting planet TOI-1416 b, with a period of 1.07d, a mass of and a radius of , implying a slightly sub-Earth
density of g cm. The RV data also further indicate a tentative
planet c with a period of 27.4 or 29.5 days, whose nature cannot be verified
due to strong suspicions about contamination by a signal related to the Moon's
synodic period of 29.53 days. The near-USP (Ultra Short Period) planet TOI-1416
b is a typical representative of a short-period and hot ( 1570
K) super-Earth like planet. A planet model of an interior of molten magma
containing a significant fraction of dissolved water provides a plausible
explanation for its composition, and its atmosphere could be suitable for
transmission spectroscopy with JWST. The position of TOI-1416 b within the
radius-period distribution corroborates that USPs with periods of less than one
day do not form any special group of planets. Rather, this implies that USPs
belong to a continuous distribution of super-Earth like planets with periods
ranging from the shortest known ones up to ~ 30 days, whose period-radius
distribution is delimitated against larger radii by the Neptune desert and by
the period-radius valley that separates super-Earths from sub-Neptune planets.
In the abundance of small-short periodic planets against period, a plateau
between periods of 0.6 to 1.4 days has however become notable that is
compatible with the low-eccentricity formation channel. For the Neptune desert,
its lower limits required a revision due to the increasing population of short
period planets and new limits are provided. These limits are also given in
terms of the planets' insolation and effective temperatures.Comment: 31 pages, 31 figures, 8 tables, accepted for publication in A&
Womenâs, partnersâ and healthcare providersâ views and experiences of assisted vaginal birth: a systematic mixed methods review
Background
When certain complications arise during the second stage of labour, assisted vaginal delivery (AVD), a vaginal birth with forceps or vacuum extractor, can effectively improve outcomes by ending prolonged labour or by ensuring rapid birth in response to maternal or fetal compromise. In recent decades, the use of AVD has decreased in many settings in favour of caesarean section (CS). This review aimed to improve understanding of experiences, barriers and facilitators for AVD use.
Methods
Systematic searches of eight databases using predefined search terms to identify studies reporting views and experiences of maternity service users, their partners, health care providers, policymakers, and funders in relation to AVD. Relevant studies were assessed for methodological quality. Qualitative findings were synthesised using a meta-ethnographic approach. Confidence in review findings was assessed using GRADE CERQual. Findings from quantitative studies were synthesised narratively and assessed using an adaptation of CERQual. Qualitative and quantitative review findings were triangulated using a convergence coding matrix.
Results
Forty-two studies (published 1985â2019) were included: six qualitative, one mixed-method and 35 quantitative. Thirty-five were from high-income countries, and seven from LMIC settings. Confidence in the findings was moderate or low. Spontaneous vaginal birth was most likely to be associated with positive short and long-term outcomes, and emergency CS least likely. Views and experiences of AVD tended to fall somewhere between these two extremes. Where indicated, AVD can be an effective, acceptable alternative to caesarean section. There was agreement or partial agreement across qualitative studies and surveys that the experience of AVD is impacted by the unexpected nature of events and, particularly in high-income settings, unmet expectations. Positive relationships, good communication, involvement in decision-making, and (believing in) the reason for intervention were important mediators of birth experience. Professional attitudes and skills (development) were simultaneously barriers and facilitators of AVD in quantitative studies.
Conclusions
Information, positive interaction and communication with providers and respectful care are facilitators for acceptance of AVD. Barriers include lack of training and skills for decision-making and use of instruments
TOI-1416: A system with a super-Earth planet with a 1.07 d period
TOI-1416 (BD+42 2504, HIP 70705) is a V =10 late G- or early K-type dwarf star. TESS detected transits in its Sectors 16, 23, and 50 with a depth of about 455 ppm and a period of 1.07 days. Radial velocities (RVs) confirm the presence of the transiting planet TOI-1416 b, which has a mass of 3.48 ± 0.47 Mâą and a radius of 1.62 ± 0.08 Râą, implying a slightly sub-Earth density of 4.500.83+0.99 g cm3. The RV data also further indicate a tentative planet, c, with a period of 27.4 or 29.5 days, whose nature cannot be verified due to strong suspicions of contamination by a signal related to the Moon s synodic period of 29.53 days. The nearly ultra-short-period planet TOI-1416 b is a typical representative of a short-period and hot (Teq â 1570 K) super-Earth-like planet. A planet model of an interior of molten magma containing a significant fraction of dissolved water provides a plausible explanation for its composition, and its atmosphere could be suitable for transmission spectroscopy with JWST. The position of TOI-1416 b within the radius-period distribution corroborates the idea that planets with periods of less than one day do not form any special group. It instead implies that ultra-short-period planets belong to a continuous distribution of super-Earth-like planets with periods ranging from the shortest known ones up to â 30 days; their period-radius distribution is delimited against larger radii by the Neptune Desert and by the period-radius valley that separates super-Earths from sub-Neptune planets. In the abundance of small, short-periodic planets, a notable plateau has emerged between periods of 0.6- 1.4 days, which is compatible with the low-eccentricity formation channel. For the Neptune Desert, its lower limits required a revision due to the increasing population of short-period planets; for periods shorter then 2 days, we establish a radius of 1.6 Râą and a mass of 0.028 Mjup (corresponding to 8.9 Mâą) as the desert s lower limits. We also provide corresponding limits to the Neptune Desert against the planets insolation and effective temperatures
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