Competing Orders in a Dipolar Bose-Fermi Mixture on a Square Optical Lattice: Mean-Field Perspective

We consider a mixture of a two-component Fermi gas and a single-component dipolar Bose gas in a square optical lattice and reduce it into an effective Fermi system where the Fermi-Fermi interaction includes the attractive interaction induced by the phonons of a uniform dipolar Bose-Einstein condensate. Focusing on this effective Fermi system in the parameter regime that preserves the symmetry of $D_4$, the point group of a square, we explore, within the Hartree-Fock-Bogoliubov mean-field theory, the phase competition among density wave orderings and superfluid pairings. We construct the matrix representation of the linearized gap equation in the irreducible representations of $D_4$. We show that in the weak coupling regime, each matrix element, which is a four-dimensional (4D) integral in momentum space, can be put in a separable form involving a 1D integral, which is only a function of temperature and the chemical potential, and a pairing-specific "effective" interaction, which is an analytical function of the parameters that characterize the Fermi-Fermi interactions in our system. We analyze the critical temperatures of various competing orders as functions of different system parameters in both the absence and presence of the dipolar interaction. We find that close to half filling, the d_{x^{2}-y^{2}}-wave pairing with a critical temperature in the order of a fraction of Fermi energy (at half filling) may dominate all other phases, and at a higher filling factor, the p-wave pairing with a critical temperature in the order of a hundredth of Fermi energy may emerge as a winner. We find that tuning a dipolar interaction can dramatically enhance the pairings with $d_{xy}$- and g-wave symmetries but not enough for them to dominate other competing phases.Comment: 18 pages, 9 figure

Primer on adult patient satisfaction in perioperative settings.

The topic of patient satisfaction has gained increasing importance over the past decade. Due to the impact of patient satisfaction on health care quality, understanding factors that predict satisfaction is vital. The purpose of this review is to examine the literature and identify factors related to patient perioperative satisfaction as well as predictive variables that, if modified, can enhance satisfaction scores of patients undergoing surgery. Our review reports that patient satisfaction scores are affected by modifiable factors such as clinician-patient communication, information provision to patients, and operational function of a hospital. Non-modifiable factors affecting patient satisfaction scores include patient demographics such as gender, age, and education. In order to enhance patient perioperative satisfaction, we suggest that anesthesiologists and surgeons focus their efforts on enhancing their communication skills and providing information that is appropriately tailored to the understanding of their patients

The Impact of Marijuana Decriminalization on Legal Permanent Residents: Why Descheduling Marijuana at the Federal Level Should Be a High Priority

Although the federal government has remained firmly committed to prohibiting marijuana, many states have legalized the drug for either medical or recreational use. Others have merely decriminalized it, lowering the penalties associated with its use such that defendants charged with marijuana-related offenses are less likely to face incarceration. Most Americans stand to benefit from this change, as it means they face fewer meaningful consequences within the criminal justice system. By contrast, noncitizen offenders, including legal permanent residents (LPRs), may actually be disadvantaged by it. For example, LPRs living in jurisdictions that have decriminalized marijuana may mistakenly believe that it is safe to admit to marijuana use when communicating with immigration agents or law enforcement personnel. Due to the broad language of the Immigration and Nationality Act, however, such an admission can result in significant, adverse immigration consequences. Additionally, decriminalization makes it is less likely that indigent LPRs will receive court-appointed counsel to advise them of the immigration consequences of pleading guilty to seemingly minor marijuana-related charges. Although legalizing marijuana at the federal level would certainly address this issue, the federal government has repeatedly failed to enact such legislation. As such, states have stepped in, implementing various programs to protect their indigent, noncitizen residents. Although each has taken significant steps in the right direction, few have tackled the issue head-on

New Evidence about Brown v. Board of Education: The Complex Effects of School Racial Composition on Achievement

Uncovering the effects of school racial composition on achievement is difficult, because racial mixing in the schools is not an accident but instead represents a complex mixture of government and family choices. While the goals of the integration of schools legally inspired by Brown v. Board of Education are very broad, here we focus more narrowly on how school racial composition effects scholastic achievement. Our evaluation, made possible by rich panel data on the achievement of Texas students, disentangles racial composition effects from other aspects of school quality and from differences in student abilities and family background. The results show that a higher percentage of Black schoolmates has a strong adverse effect on achievement of Blacks and, moreover, that the effects are highly concentrated in the upper half of the ability distribution. In contrast, racial composition has a noticeably smaller effect on achievement of lower ability blacks, of whites, and of Hispanics -- strongly suggesting that the results are not a simple reflection of unmeasured school quality.

Do Higher Salaries Buy Better Teachers?

Important policy decisions rest on the relationship between teacher salaries and the quality of teachers, but the evidence about the strength of any such relationship is thin. This paper relies upon the matched panel data of the UTD Texas School Project to investigate how shifts in salary schedules affect the composition of teachers within a district. The panel data permit separation of shifts in salary schedules from movement along given schedules, and thus the analysis is much more closely related to existing policy proposals. In analyses both of teacher mobility and of student performance, teacher salaries are shown to have a modest impact. Teacher mobility is more affected by characteristics of the students (income, race, and achievement) than by salary schedules. Salaries are also weakly related to performance on teacher certification tests appearing to be relevant only in districts doing high levels of hiring, but preliminary examination shows that the certification tests are not significantly related to student achievement. The only significant relationship between salaries and student achievement holds (implausibly) for existing experienced teachers and not for new hires or for probationary teachers.

Why Public Schools Lose Teachers

Many school districts experience difficulties attracting and retaining teachers, and the impending retirement of a substantial fraction of public school teachers raises the specter of severe shortages in some public schools. Schools in urban areas serving economically disadvantaged and minority students appear particularly vulnerable. This paper investigates those factors that affect the probabilities that teachers switch schools or exit the public schools entirely. The results indicate that teacher mobility is much more strongly related to characteristics of the students, particularly race and achievement, than to salary, although salary exerts a modest impact once compensating differentials are taken into account.

Estimation of Localized Ideal Oximetry Sensor Lag Via Oxygen Desaturation-Disordered Breathing Event Cross-Correlation

In previous work, we attempted to identify events using sensor data from full-night polysomnography studies using a global 20-second oximetry sensor lag across all studies. However, we observed that oxygen desaturation onset trailed the corresponding human expert-labeled events by varying amounts of time, even within the same study. In this work, we estimate the localized ideal oximetry (SpO2) sensor lag using the cross-correlation between the labeled disordered breathing event and the observed desaturation

The Market for Teacher Quality

Much of education policy focuses on improving teacher quality, but most policies lack strong research support. We use student achievement gains to estimate teacher value-added, our measure of teacher quality. The analysis reveals substantial variation in the quality of instruction, most of which occurs within rather than between schools. Although teacher quality appears to be unrelated to advanced degrees or certification, experience does matter -- but only in the first year of teaching. We also find that good teachers tend to be effective with all student ability levels but that there is a positive value of matching students and teachers by race. In the second part of the analysis, we show that teachers staying in our sample of urban schools tend to be as good as or better than those who exit. Thus, the main cost of large turnover is the introduction of more first year teachers. Finally, there is little or no evidence that districts that offer higher salaries and have better working conditions attract the higher quality teachers among those who depart the central city district. The overall results have a variety of direct policy implications for the design of school accountability and the compensation of teachers.

Does Peer Ability Affect Student Achievement?

Empirical analysis of peer effects on student achievement has been open to question because of the difficulties of separating peer effects from other confounding influences. While most econometric attention has been directed at issues of simultaneous determination of peer interactions, we argue that issues of omitted and mismeasured variables are likely to be more important. We control for the most important determinants of achievement that will confound peer estimates by removing student and school-by-grade fixed effects in addition to observable family and school characteristics. The analysis also addresses the reciprocal nature of peer interactions and the interpretation of estimates based upon models using past achievement as the measure of peer group quality. The results indicate that peer achievement has a positive effect on achievement growth. Moreover, students throughout the school test score distribution appear to benefit from higher achieving schoolmates. On the other hand, the variance in achievement appears to have no systematic effect.