Miracle-dz/UniFAR-FTUs huggingface dataset:
The Stability of the Thermohaline Circulation in Global Warming Experiments

A simplified climate model of the coupled ocean‐atmosphere system is used to perform extensive sensitivity studies concerning possible future climate change induced by anthropogenic greenhouse gas emissions. Supplemented with an active atmospheric hydrological cycle, experiments with different rates of CO 2 increase and different climate sensitivities are performed. The model exhibits a threshold value of atmospheric CO 2 concentration beyond which the North Atlantic Deep Water formation stops and never recovers. For a climate sensitivity that leads to an equilibrium warming of 3.68C for a doubling of CO2 and a rate of CO2 increase of 1% yr21, the threshold lies between 650 and 700 ppmv. Moreover, it is shown that the stability of the thermohaline circulation depends on the rate of increase of greenhouse gases. For a slower increase of atmospheric pCO2 the final amount that can be reached without a shutdown of the circulation is considerably higher. This rate-sensitive response is due to the uptake of heat and excess freshwater from the uppermost layers to the deep ocean. The increased equator-to-pole freshwater transport in a warmer atmosphere is mainly responsible for the cessation of deep water formation in the North Atlantic. Another consequence of the enhanced latent heat transport is a stronger warming at high latitudes. A model version with fixed water vapor transport exhibits uniform warming at all latitudes. The inclusion of a simple parameterization of the ice-albedo feedback increases the model sensitivity and further decreases the pole-to-equator temperature difference in a greenhouse climate. The possible range of CO2 threshold concentrations and its dependency on the rate of CO 2 increase, on the climate sensitivity, and on other model parameters are discussed.
Assessing Knowledge Structures in a Constructive Statistical Learning Environment

In this report, the method of free recall is put forward as a tool to evaluate a prototypical statistical learning environment. A number of students from the faculty of Health Sciences, Maastricht University, the Netherlands, were required to write down whatever they could remember of a statistics course in which they had participated. By means of examining the free recall protocols of the participants, insight can be obtained into the mental representations they had formed with respect to three statistical concepts. Quantitative as well as qualitative analyses of the free recall protocols showed that the effect of the constructive learning environment was not in line with the expectations. Despite small-group discussions on the statistical concepts, students appeared to have disappointingly low levels of conceptual understanding.
Is Learning by Migrating to a Megalopolis Really Important? Evidence from Thailand

We examine the effects of learning by migrating on the productivity of migrants who move to a "megalopolis" from rural areas using the Thailand Labor Force Survey. The main contribution is to the development a simple framework to test for self-selection on migration decisions and learning by migrating into the urban labor market, focusing on experimental evidence in the observational data. The role of the urban labor market is examined. In conclusion, we find significant evidence for sorting: the self-selection effects test (1) is positive among new entrants from rural areas to the urban labor market; and (2) is negative among new exits that move to rural areas from the urban labor market. Further, estimated effects of learning by migrating into a "megalopolis" have a less significant impact. These results suggest the existence of a natural selection (i.e. survival of the fittest) mechanism in the urban labor market in a developing economy.
The pros and cons of using micro-computed tomography in gross and microanatomical assessments of polychaetous annelids

Paterson, G.L. J., Sykes, D. , Faulwetter, S. , Merks, R. , Ahmed, F. , Hawkins, L.E. , Dinley, J., Ball, A.D. and Arvanitidis, C. 2014. The pros and cons of using micro-computed tomography in gross and micro-anatomical assessments of polychaetous annelids. Memoirs of Museum Victoria 71: 237–246. The use of micro-CT scanners in the study of anatomy and functional morphology of marine invertebrates is becoming more common. The advantages and disadvantages of this methodology for the study of the internal anatomy of polychaetes are discussed. Soft-bodied invertebrates such as polychaetes pose some specific problems. It can be difficult to gain sufficient contrast between different types of tissues to be able to image them with X-rays. A range of stains can help enhance the contrast between tissues. In this study we investigate a number of stains, concentrating on those considered reversible. The advantages of such stains in the study of museum specimens and the resulting possibilities for large-scale comparative morphology studies are outlined.
SUBMILLIMETER ARRAY OBSERVATIONS OF THE RX J1633.9-2442 TRANSITION DISK: EVIDENCE FOR MULTIPLE PLANETS IN THE MAKING

We present continuum high-resolution Submillimeter Array (SMA) observations of the transition disk object RX J1633.9-2442, which is located in the Ophiuchus molecular cloud and has recently been identified as a likely site of ongoing giant planet formation. The observations were taken at 340 GHz (880 μm) with the SMA in its most extended configuration, resulting in an angular resolution of 0. ″3 (35 AU at the distance of the target). We find that the disk is highly inclined (i ∼ 50°) and has an inner cavity ∼25 AU in radius, which is clearly resolved by our observations. We simultaneously model the entire optical to millimeter wavelength spectral energy distribution and SMA visibilities of RX J1633.9-2442 in order to constrain the structure of its disk. We find that an empty cavity ∼25 AU in radius is inconsistent with the excess emission observed at 12, 22, and 24 μm. Instead, the mid-IR excess can be modeled by either a narrow, optically thick ring at ∼10 AU or an optically thin region extending from ∼7 AU to ∼25 AU. The inner disk (r ≲ 5 AU) is mostly depleted of small dust grains as attested by the lack of detectable near-IR excess. We also present deep Keck aperture masking observations in the near-IR, which rule out the presence of a companion up to 500 times fainter than the primary star (in K band) for projected separations in the 5–20 AU range. We argue that the complex structure of the RX J1633.9-2442 disk is best explained by multiple planets embedded within the disk. We also suggest that the properties and incidence of objects such as RX J1633.9-2442, T Cha, and LkCa 15 (and those of the companions recently identified to these two latter objects) are most consistent with the runaway gas accretion phase of the core accretion model, when giant planets gain their envelopes and suddenly become massive enough to open wide gaps in the disk.
Explicit Directivity-Pulse Inclusion in Probabilistic Seismic Hazard Analysis

Probabilistic seismic hazard analysis (PSHA) is widely used to estimate the ground motion intensity that should be considered when assessing a structure's performance. Disaggregation of PSHA is often used to identify representative ground motions in terms of magnitude and distance for structural analysis. Forward directivity–induced velocity pulses, which may occur in near-fault (or near-source) motions, are known to cause relatively severe elastic and inelastic response in structures of certain periods. Here, the principles of PSHA are extended to incorporate the possible occurrence of a velocity pulse in a near-fault ground motion. For each magnitude and site-source geometry, the probability of occurrence of a pulse is considered along with the probability distribution of the pulse period given that a pulse does occur. A near-source “narrowband” attenuation law modification to predict ground motion spectral acceleration ( Sa ) amplitude that takes advantage of this additional pulse period information is utilized. Further, disaggregation results provide the probability that a given level of ground motion intensity is caused by a pulse-like ground motion, as well as the conditional probability distribution of the pulse period associated with that ground motion. These extensions improve the accuracy of PSHA for sites located near faults, as well as provide a rational basis for selecting appropriate near-fault ground motions to be used in the dynamic analyses of a structure.
Numerical Analysis of Effect of Boundary Layer Characteristics on the Flow Field in S-shaped Inlet

In order to explore the effect of boundary layer thickness and pressure gradient on the perfor- mance of the flow field in the inlet, we design a high offset rate S-shaped inlet based on a certain unmanned aeri- al vehicle (UAV), and its author has analyzed the effect of boundary layer characteristics on the inlet with nu- merical simulation method. The suction of boundary layer which leads to separation zone not only becomes longer in the inlet, but also moves to the center plane of symmetry, the separation point of boundary layer ap- pears in advance as pressure gradient increases. Considering the influence of the boundary layer, various perfor- mance parameters all exceeds that of the uniform entrance inlet conditions, especially the circumferential total pressure distortion of outlet increased by 58.2% at most, obviously can't meet the engine to work properly, so we must consider and pay attention to the effect of the boundary layer characteristics on the flow field in the S-shaped inlet.
Photodissociation and chemistry of N2 in the circumstellar envelope of carbon-rich AGB stars

Context. The envelopes of asymptotic giant branch (AGB) stars are irradiated externally by ultraviolet photons; hence, the chemistry is sensitive to the photodissociation of N2 and CO, which are major reservoirs of nitrogen and carbon, respectively. The photodissociation of N2 has recently been quantified by laboratory and theoretical studies. Improvements have also been made for CO photodissociation. Aims. For the first time, we use accurate N2 and CO photodissociation rates and shielding functions in a model of the circumstellar envelope of the carbon-rich AGB star, IRC +10216. Methods. We use a state-of-the-art chemical model of an AGB envelope, the latest CO and N2 photodissociation data, and a new method for implementing molecular shielding functions in full spherical geometry with isotropic incident radiation. We compare computed column densities and radial distributions of molecules with observations. Results. The transition of N2→ N (also, CO → C → C+) is shifted towards the outer envelope relative to previous models. This leads to different column densities and radial distributions of N-bearing species, especially those species whose formation/destruction processes largely depend on the availability of atomic or molecular nitrogen, for example, CnN (n = 1, 3, 5), CnN− (n = 1, 3, 5), HCnN (n = 1, 3, 5, 7, 9), H2CN and CH2CN. Conclusions. The chemistry of many species is directly or indirectly affected by the photodissociation of N2 and CO, especially in the outer shell of AGB stars where photodissociation is important. Thus, it is important to include N2 and CO shielding in astrochemical models of AGB envelopes and other irradiated environments. In general, while differences remain between our model of IRC +10216 and the observed molecular column densities, better agreement is found between the calculated and observed radii of peak abundance.
Comparative productivity of irrigated short-term ryegrass (Lolium multiflorum) pasture receiving nitrogen, grown alone or in a mixture with white (Trifolium repens) and Persian (T. resupinatum) clovers

Dairy farms in subtropical Australia use irrigated, annually sown short-term ryegrass (Lolium multiflorum) or mixtures of short-term ryegrass and white (Trifolium repens) and Persian (shaftal) (T. resupinatum) clover during the winter-spring period in all-year-round milk production systems. A series of small plot cutting experiments was conducted in 3 dairying regions (tropical upland, north Queensland, and subtropical southeast Queensland and northern New South Wales) to determine the most effective rate and frequency of application of nitrogen (N) fertiliser. The experiments were not grazed, nor was harvested material returned to the plots, after sampling. Rates up to 100 kg N/ha.month (as urea or calcium ammonium nitrate) and up to 200 kg N/ha every 2 months (as urea) were applied to pure stands of ryegrass in 1991. In 1993 and 1994, urea, at rates up to 150 kg N/ha.month and to 200 kg N/ha every 2 months, was applied to pure stands of ryegrass; urea, at rates up to 50 kg N/ha.month, was also applied to ryegrass-clover mixtures. The results indicate that applications of 50-85 kg N/ha.month can be recommended for short-term ryegrass pastures throughout the subtropics and tropical uplands of eastern Australia, irrespective of soil type. At this rate, dry matter yields will reach about 90% of their potential, forage nitrogen concentration will be increased, there is minimal risk to stock from nitrate poisoning and there will be no substantial increase in soil N. The rate of N for ryegrass-clover pastures is slightly higher than for pure ryegrass but, at these rates, the clover component will be suppressed. However, increased ryegrass yields and higher forage nitrogen concentrations will compensate for the reduced clover component. At application rates up to 100 kg N/ha.month, build-up of NO3--N and NH4+-N in soil was generally restricted to the surface layers (0-20 cm) of the soil, but there was a substantial increase throughout the soil profile at 150 kg N/ha.month. The build-up of NO3--N and NH4+-N was greater and was found at lower rates on the lighter soil compared with heavy clays. Generally, most of the soil N was in the NO3--N form and most was in the top 20 cm.
Recent limnological changes and their implication on fisheries in Lake Baringo, Kenya

Water samples for physico-chemical analysis for this study were collected monthly for five years between April 2008 and March 2013. Conductivity, temperature, dissolved oxygen and pH was measured in situ using a Surveyor II model hydrolab. Chlorophyll-a concentration was determined using a Genesys 10S Vis spectrophotomer. Nutrients were determined using standard methods and procedures. Analysis of Variance (ANOVA) was used to determine spatial and temporal variation in physico-chemical and biological factors. Principal component analysis (PCA) was performed to establish the correlation of the physico-chemical and biological parameters among sampling stations and to group stations with similar physico-chemical parameters. Both spatial and temporal significant variations (P < 0.05) were detected in the concentrations of the nutrients measured during the study. Key words: Limnological changes, parameters, Lake Baringo, Kenya.
The Stability of Mode Preferences: Implications for Tailoring in Longitudinal Surveys

One suggested tailoring strategy for longitudinal surveys is giving respondents their preferred mode. Mode preference could be collected at earlier waves and used when introducing a mixed-mode design. The utility of mode preference is in question, however, due to a number of findings suggesting that preference is an artefact of mode of survey completion, and heavily affected by contextual factors. Conversely, recent findings suggest that tailoring on mode preference may lead to improved response outcomes and data quality. The current study aims to ascertain whether mode preference is a meaningful construct with utility in longitudinal surveys through analysis of data providing three important features: multiple measurements of mode preference over time; an experiment in mode preference question order; and the repeated measures within respondents collected both prior and after the introduction of mixed-mode data collection. Results show that mode preference is not a stable attitude for a large percentage of respondents, and that these responses are affected by contextual factors. However, a substantial percentage of respondents do provide stable responses over time, and may explain the positive findings elsewhere. Using mode preference to tailor longitudinal surveys should be done so with caution, but may be useful with further understanding.
Board structure as a defense mechanism during periods of economic downturn, evidence from the 2007-2008 financial crisis in the UK.

This paper contributes to the existing corporate governance literature in the United Kingdom. In the 2007-2008 financial crisis, many firms faced adverse firm performance or went bankrupt. This paper tried to reveal a possible ability of board structure to shield against adverse firm performance during periods of economic downturn in the UK. A multiple hierarchal regression method was used to come up with the results, these were controlled with a sensitivity analysis. The random sample in this paper existed of 466 industrial firms listed on the London Stock exchange. The results did not reveal clear or obvious relations between board structure and firm performance during the 2007-2008 crisis. However, evidence was presented for a weak positive relation between board size and firm performance, this connection was confirmed in the sensitivity analysis. This might be confirmation of the claim of Essen et al (2013) that board discretion is desired in periods of economic downturn. Therefore this work can serve as a source of inspiration for future research into the relation between governance mechanisms and firm performance during periods of economic downturn in Anglo-Saxon markets. Connections in those markets appear to be different compared to periods of economic stability.
Immigration, Endogenous Technology Adoption and Wages

We document that immigration to U.S. states has increased the mass of workers at the lower range of the skill distribution. We use this change in skill distribution of workers to analyze the effect of immigration on wages. Our model allows firms to endogenously respond to the immigration-induced changes in skill distribution in terms of their decisions (i) to enter different industries which require the use of different technologies; (ii) to choose across technologies that differ in their skill-intensity; and (iii) to employ workers of different skill levels. Allowing these mechanisms to interact, we find that, in line with much of the related empirical literature, immigration has a small effect on average real wages of low skilled workers for U.S. states. We further show that immigration increases the wage inequality between workers of different skill levels in all states, and that the effect of immigration on wages and wage inequality varies systematically with the volume of immigration across states.
PRACTICES REGARDING SECONDHAND SMOKING AMONG MALAY HOUSEWIVES IN RURAL COMMUNITY IN JEMPOL, NEGERI SEMBILAN

ABSTRACT Introduction: Secondhand smoking occurs in public and private spaces and it causes serious adverse health effects. The initiatives to establish smoke free policies in private spaces are more challenging as it is an area of autonomy. Thus, this study aims determine the knowledge, attitude and practices of a group of housewives in a Malay community who were secondhand smokers in the privacy of their own homes and their association with these women’s socio demographic profiles. Methods: A total of 114 housewives who lived with at least one smoker participated in this study. A self-administered questionnaire was used to collect the characteristics of the respondents (age, level of education and income), their knowledge, attitude and practices towards secondhand smoking and also information about their secondhand smoking. Their practices were then categorized into ‘appropriate’ and ‘not appropriate’ practices. It was then tested for association with age, level of education, income, knowledge and attitude categories. Results : The mean age of the respondents was 42.12±11.13 years, 56.1% of them at least finished primary school and 90.4% had monthly household income of less than RM 2000. Exposure to secondhand smoking at home was 59.6%. Most were exposed to less than 10 cigarettes and less than 10 minutes per day (69.3% and 49.1%, respectively). A total 66.7% of the respondents had appropriate practice towards secondary smoking and this practice was significantly associated with the level of knowledge about secondary smoking ( P =0.034). Conclusion: National efforts to suppress smoking in private spaces such as homes and cars need to be enhanced. As knowledge is significantly associated with appropriate practice towards secondary smoking, more efforts should be made to increase and disseminate knowledge about the harmful effects of secondhand smoking especially to second hand smokers. Key Words: knowledge, attitude, practice, secondary smoking, housewife
The Epidemic of Mental Illness: Why?

It seems that Americans are in the midst of a raging epidemic of mental illness, at least as judged by the increase in the numbers treated for it. The tally of those who are so disabled by mental disorders that they qualify for Supplemental Security Income (SSI) or Social Security Disability Insurance (SSDI) increased nearly two and a half times between 1987 and 2007— from one in 184 Americans to one in seventy-six. For children, the rise is even more startling—a thirty-five-fold increase in the same two decades. Mental illness is now the leading cause of disability in children, well ahead of physical disabilities like cerebral palsy or Down syndrome, for which the federal programs were created.
Errors, chaos, and the collisionless limit

We simultaneously study the dynamics of the growth of errors and the question of the faithfulness of simulations of $N$-body systems. The errors are quantified through the numerical reversibility of small-$N$ spherical systems, and by comparing fixed-timestep runs with different stepsizes. The errors add randomly, before exponential divergence sets in, with exponentiation rate virtually independent of $N$, but scale saturating as $\sim 1/\sqrt{N}$, in line with theoretical estimates presented. In a third phase, the growth rate is initially driven by multiplicative enhancement of errors, as in the exponential stage. It is then qualitatively different for the phase space variables and mean field conserved quantities (energy and momentum); for the former, the errors grow systematically through phase mixing, for the latter they grow diffusively. For energy, the $N$-variation of the `relaxation time' of error growth follows the $N$-scaling of two-body relaxation. This is also true for angular momentum in the fixed stepsize runs, although the associated error threshold is higher and the relaxation time smaller. Due to shrinking saturation scales, the information loss associated with the exponential instability decreases with $N$ and the dynamical entropy vanishes at any finite resolution as $N \rightarrow \infty$. A distribution function depending on the integrals of motion in the smooth potential is decreasingly affected. In this sense there is convergence to the collisionless limit, despite the persistence of exponential instability on infinitesimal scales. Nevertheless, the slow $N$-variation in its saturation points to the slowness of the convergence.