Abstract Mass, radius, and age measurements of young (≲100 Myr) planets have the power to shape our understanding of planet formation. However, young stars tend to be extremely variable in both ...photometry and radial velocity (RV) measurements, which makes constraining these properties challenging. The V1298 Tau system of four ∼0.5 R J planets transiting a pre-main-sequence star presents an important, if stress-inducing, opportunity to observe and measure directly the properties of infant planets. Suárez Mascareño et al. published radial-velocity-derived masses for two of the V1298 Tau planets using a state-of-the-art Gaussian process regression framework. The planetary densities computed from these masses were surprisingly high, implying extremely rapid contraction after formation in tension with most existing planet-formation theories. In an effort to constrain further the masses of the V1298 Tau planets, we obtained 36 RVs using Keck/HIRES, and analyzed them in concert with published RVs and photometry. Through performing a suite of cross-validation tests, we found evidence that the preferred model of Suárez Mascareño et al. suffers from overfitting, defined as the inability to predict unseen data, rendering the masses unreliable. We detail several potential causes of this overfitting, many of which may be important for other RV analyses of other active stars, and recommend that additional time and resources be allocated to understanding and mitigating activity in active young stars such as V1298 Tau.
Abstract
We measured the Rossiter–McLaughlin effect of WASP-107b during a single transit with Keck/HIRES. We found the sky-projected inclination of WASP-107b’s orbit, relative to its host star’s ...rotation axis, to be
degrees. This confirms the misaligned/polar orbit that was previously suggested from spot-crossing events and adds WASP-107b to the growing population of hot Neptunes in polar orbits around cool stars. WASP-107b is also the fourth such planet to have a known distant planetary companion. We examined several dynamical pathways by which this companion could have induced such an obliquity in WASP-107b. We find that nodal precession and disk dispersal-driven tilting can both explain the current orbital geometry while Kozai–Lidov cycles are suppressed by general relativity. While each hypothesis requires a mutual inclination between the two planets, nodal precession requires a much larger angle, which for WASP-107 is on the threshold of detectability with future Gaia astrometric data. As nodal precession has no stellar type dependence, but disk dispersal-driven tilting does, distinguishing between these two models is best done on the population level. Finding and characterizing more extrasolar systems like WASP-107 will additionally help distinguish whether the distribution of hot-Neptune obliquities is a dichotomy of aligned and polar orbits or if we are uniformly sampling obliquities during nodal precession cycles.
Immunotherapy of cancers comes of age Yousefi, Hila; Yuan, Jianda; Keshavarz-Fathi, Mahsa ...
Expert review of clinical immunology,
10/2017, Letnik:
13, Številka:
10
Journal Article
Recenzirano
Introduction: Cancer immunotherapy has evolved and is aimed at generating the efficacious therapeutic modality to enhance the specificity and power of the immune system to combat tumors.
Areas ...covered: Current efforts in cancer immunotherapy fall into three main approaches. One approach is through the blockade of immune checkpoints, another approach is through adoptive cellular therapy, and the last approach is through vaccination. The goal of this review is to summarize the current understanding and status of cancer immunotherapy in these three categories.
Expert commentary: We foresee the development of therapeutic protocols combining these approaches with each other or conventional therapies to achieve the most appropriate guideline for management of cancer.
Abstract TOI-561 is a galactic thick-disk star hosting an ultra-short-period (0.45-day-orbit) planet with a radius of 1.37 R ⊕ , making it one of the most metal-poor (Fe/H = −0.41) and oldest (≈10 ...Gyr) sites where an Earth-sized planet has been found. We present new simultaneous radial velocity (RV) measurements from Gemini-N/MAROON-X and Keck/HIRES, which we combined with literature RVs to derive a mass of M b = 2.24 ± 0.20 M ⊕ . We also used two new sectors of TESS photometry to improve the radius determination, finding R b = 1.37 ± 0.04 R ⊕ and confirming that TOI-561 b is one of the lowest-density super-Earths measured to date ( ρ b = 4.8 ± 0.5 g cm −3 ). This density is consistent with an iron-poor rocky composition reflective of the host star’s iron and rock-building element abundances; however, it is also consistent with a low-density planet with a volatile envelope. The equilibrium temperature of the planet (∼2300 K) suggests that this envelope would likely be composed of high mean molecular weight species, such as water vapor, carbon dioxide, or silicate vapor, and is likely not primordial. We also demonstrate that the composition determination is sensitive to the choice of stellar parameters and that further measurements are needed to determine whether TOI-561 b is a bare rocky planet, a rocky planet with an optically thin atmosphere, or a rare example of a nonprimordial envelope on a planet with a radius smaller than 1.5 R ⊕ .
"Bottling Fog" is the culmination of 50 years of work to capture the core ingredients of leadership. Joseph Murphy, a preeminent scholar of leadership, has compiled this book of short and thoughtful ...lessons designed for today's busy professional. The lessons come from reading, seeing, and hearing about leadership in various sectors of practice. Murphy unpacks the nucleus of leadership and presents it in a way that we rarely find--seeing the fog and shaping it into meaningful forms, not textbooks or lectures, but lessons. Each lesson represents a profound slice of understanding for leaders, crafted so that they will not forget these insights as soon as they walk to their cars at the end of the day. The book features: (1) Concise and powerful lessons on leadership; (2) Immediately useful to the everyday practice of leaders; (3) Drawn from a professional lifetime of examining the complexities of practice; and (4) A user-friendly style with no academic language.
BACKGROUND:The association between new-onset left ventricular (LV) dysfunction during sepsis with long-term heart failure outcomes is lesser understood.
METHODS:Retrospective cohort study of all ...adult patients with severe sepsis and septic shock between 2007 and 2014 who underwent echocardiography within 72 h of admission to the intensive care unit. Patients with prior heart failure, LV dysfunction, and structural heart disease were excluded. LV systolic dysfunction was defined as LV ejection fraction <50% and LV diastolic dysfunction as ≥grade II. Primary composite outcome included new hospitalization for acute decompensated heart failure and all-cause mortality at 2-year follow-up. Secondary outcomes included persistent LV dysfunction, and hospital mortality and length of stay.
RESULTS:During this 8-year period, 434 patients with 206 (48%) patients having LV dysfunction were included. The two groups had similar baseline characteristics, but those with LV dysfunction had worse function as demonstrated by worse LV ejection fraction, cardiac index, and LV diastolic dysfunction. In the 331 hospital survivors, new-onset acute decompensated heart failure hospitalization did not differ between the two cohorts (15% vs. 11%). The primary composite outcome was comparable at 2-year follow-up between the groups with and without LV dysfunction (P = 0.24). Persistent LV dysfunction was noted in 28% hospital survivors on follow-up echocardiography. Other secondary outcomes were similar between the two groups.
CONCLUSIONS:In patients with severe sepsis and septic shock, the presence of new-onset LV dysfunction did not increase the risk of long-term adverse heart failure outcomes.
Gastrointestinal (GI) ischemia during exercise is associated with luminal permeability and increased systemic lipopolysaccharides (LPS). This study aimed to assess the impact of a multistrain ...pro/prebiotic/antioxidant intervention on endotoxin unit levels and GI permeability in recreational athletes. Thirty healthy participants (25 males, 5 females) were randomly assigned either a multistrain pro/prebiotic/antioxidant (LAB⁴
; 30 billion CFU·day
containing 10 billion CFU·day
CUL-60 (NCIMB 30157), 10 billion CFU·day
CUL-21 (NCIMB 30156), 9.5 billion CFU·day
CUL-20 (NCIMB 30172) and 0.5 billion CFU·day
subspecies
CUL-34 (NCIMB 30153)/55.8 mg·day
fructooligosaccharides/ 400 mg·day
α-lipoic acid, 600 mg·day
-acetyl-carnitine); matched pro/prebiotic (LAB⁴) or placebo (PL) for 12 weeks preceding a long-distance triathlon. Plasma endotoxin units (via
amebocyte lysate chromogenic quantification) and GI permeability (via 5 h urinary lactulose (L): mannitol (M) recovery) were assessed at baseline, pre-race and six days post-race. Endotoxin unit levels were not significantly different between groups at baseline (LAB⁴
: 8.20 ± 1.60 pg·mL
; LAB⁴: 8.92 ± 1.20 pg·mL
; PL: 9.72 ± 2.42 pg·mL
). The use of a 12-week LAB⁴
intervention significantly reduced endotoxin units both pre-race (4.37 ± 0.51 pg·mL
) and six days post-race (5.18 ± 0.57 pg·mL
;
= 0.03, ηp² = 0.35), but only six days post-race with LAB⁴ (5.01 ± 0.28 pg·mL
;
= 0.01, ηp² = 0.43). In contrast, endotoxin units remained unchanged with PL. L:M significantly increased from 0.01 ± 0.01 at baseline to 0.06 ± 0.01 with PL only (
= 0.004, ηp² = 0.51). Mean race times (h:min:s) were not statistically different between groups despite faster times with both pro/prebiotoic groups (LAB⁴
: 13:17:07 ± 0:34:48; LAB⁴: 12:47:13 ± 0:25:06; PL: 14:12:51 ± 0:29:54;
> 0.05). Combined multistrain pro/prebiotic use may reduce endotoxin unit levels, with LAB⁴
potentially conferring an additive effect via combined GI modulation and antioxidant protection.
The Hessian fly (Mayetiola destructor Say) is a gall midge that infests and feeds upon wheat (Triticum aestivum L.). Recently, a new form of tolerance (QHft.nc‐7D) was identified in the breeding line ...LA03136E71 (PI 700336). Partial resistance allows immature Hessian fly to thrive in small numbers and does not function like antibiosis. Little is known about the potential yield drag of using partial resistance. In this study, we evaluated six genotypes: one containing QHft.nc‐7D (LA03136E71), one containing H13, and four potentially susceptible genotypes. All genotypes were evaluated with two different seed treatment regiments of imidacloprid: no treatment and a two times rate of imidacloprid. All tested genotypes were planted in six‐to‐eight replications of a full factorial design in four environments. Subsamples of yield trial plots were taken to measure percent infested tillers and a number of larvae/pupae per tiller. Plots were harvested and grain yield was recorded. There was a significant (p>F < 0.05) reduction of percent infested tillers and a number of larvae/pupae per tiller related to the imidacloprid treatment. Imidacloprid treatment significantly (p>T < 0.05) reduced the number of larvae/pupae per tiller for LA03136E71. There was no significant (p>T > 0.05) grain yield increase associated with treatment for LA03136E71. This indicates that a two times application of imidacloprid on LA03136E71 (QHft.nc‐7D) did not improve yield yet reduced infestation. Therefore, QHft.nc‐7D, while allowing Hessian fly to thrive on the plant, does not significantly compromise yield.
Core Ideas
Application of a two‐times regiment of imidacloprid provides yield protection for susceptible genotypes.
Partial resistance and/or tolerance to Hessian fly (QHft.nc‐7D) yields similarly regardless of seed treatment.
Antibiosis‐based Hessian fly resistance (H13) yields similarly regardless of seed treatment.
Partial resistance and/or tolerance, while allowing Hessian fly to persist, does not compromise yield.
Abstract
Exoplanet systems with multiple transiting planets are natural laboratories for testing planetary astrophysics. One such system is HD 191939 (TOI 1339), a bright (
V
= 9) and Sun-like (G9V) ...star, which TESS found to host three transiting planets (b, c, and d). The planets have periods of 9, 29, and 38 days each with similar sizes from 3 to 3.4
R
⊕
. To further characterize the system, we measured the radial velocity (RV) of HD 191939 over 415 days with Keck/HIRES and APF/Levy. We find that
M
b
= 10.4 ± 0.9
M
⊕
and
M
c
= 7.2 ± 1.4
M
⊕
, which are low compared to most known planets of comparable radii. The RVs yield only an upper limit on
M
d
(<5.8
M
⊕
at 2
σ
). The RVs further reveal a fourth planet (e) with a minimum mass of 0.34 ± 0.01
M
Jup
and an orbital period of 101.4 ± 0.4 days. Despite its nontransiting geometry, secular interactions between planet e and the inner transiting planets indicate that planet e is coplanar with the transiting planets (Δ
i
< 10°). We identify a second high-mass planet (f) with 95% confidence intervals on mass between 2 and 11
M
Jup
and period between 1700 and 7200 days, based on a joint analysis of RVs and astrometry from Gaia and Hipparcos. As a bright star hosting multiple planets with well-measured masses, HD 191939 presents many options for comparative planetary astronomy, including characterization with JWST.
Students engage in risky health-related behaviours that influence their current and future health status. Health-related behaviours cluster among adults and differently based on sub-populations ...characteristics but research is lacking for university populations. Examining the clustering of health- related behaviours can inform our initiatives and strategies, while examining cluster members' characteristics can help target those who can prosper most from health promotion efforts. This study examines the clustering of health-related behaviours in Irish university students, and investigates the relationship with students' sex, age, field of study and accommodation type.
An online survey was completed by 5672 Irish university students (51.3% male; 21.60 ± 5.65 years) during 2014. Two-step cluster analysis was used to understand how health-related behaviours (physical activity, smoking, alcohol intake, drug use and dietary habits) cluster among male and female students. Binary logistic regressions were conducted to examine the likelihood of students falling into certain clusters based on their characteristics.
Five cluster groups were identified in males and four in females. A quarter of males were categorised as ideal healthy with older students and those from certain fields of study having a higher likelihood of being classified in a low physical activity and poor diet (OR = 1.06-2.89), alcohol consumption (OR = 1.03-3.04), or smoking and drug use (OR = 1.06-2.73) cluster. Forty-five percent of females were categorised as ideal healthy with older females more likely to be in a low active and smoking cluster (OR = 1.03), and less likely to be in a convenience food cluster (OR = 0.96). Females from certain fields of study were also more likely to be classified in these clusters (OR = 1.59-1.76). Students living away from their family home had in increased likelihood of being in a cluster related to a higher frequency of alcohol consumption (OR = 1.72-3.05).
Health-related behaviours cluster among this population and need to be taken into account when designing multi-health interventions and policies. These findings can be used to target student groups at risk, leading to more efficient and successful health promotion efforts. The addition of modules providing information regarding health-related behaviours are advised in all fields of study.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
