Autonomous and Financial Mortgage Prepayment

Using individual data from Freddie Mac's portfolio of conventional mortgages, this paper estimates prepayment probabilities as a function of characteristics pertaining to the borrower, the loan, regional, and economic variables. Distinction is made between induced and autonomous prepayments. Based on the curvature of the underlying termination pattern, nonparametric methods are derived to estimate the prepayment probabilities and to predict a mortgage life under various scenarios. The findings point to a response asymmetry with respect to the level and trend of interest rates. Non-interest effects reveal the significance of the borrower's characteristics, property age, and regional mobility rates on mortgage termination.

On the Integration of Emerging Stock Markets in the Middle East

Results from the Johansen-Juselius test suggest that the Middle East emerging stock markets are segmented globally, but appear highly integrated within the region. Moreover, the Gonzalo- Granger test, in conjunction with error-correction models, indicates that the market in Egypt is a dominant force driving other markets in the region. The apparent segmentation of the markets in the Middle East from the global market implies that these emerging markets provide international investors with potential diversification gains.

Qatar National Bank and Degree of Solvency

In June 2017, four countries in the Middle East led by Saudi Arabia imposed an embargo on Qatar. In response, confidence in Qatari banks was considerably shaken. Our research investigates the evolution in the Probability of Default (PD) of Qatar National Bank (QNB), the largest financial institution in Qatar using Merton’s distance to default methodology. We contrast the level of the PD during 5 critical events in the region and observe how these incidents have impacted the credit risk of QNB

Wildlife Activity Patterns at a Constructed Wetland Based On Trail Cam Monitoring

Wetland habitats fill vital environmental roles because they potentially increase wildlife diversity and provide important ecosystem services. During 2015, the Outdoor Discovery Center (ODC) in Holland began reconstructing a wetland from an agricultural field, hoping to improve wildlife diversity. However, this site is near a regional airport, which raised some concern regarding the potential for increased aviation collision risk. In order to evaluate the success of the wetland in attracting wildlife and the potential wildlife hazard to aviation, we analyzed over 600,000 trail cam photos from 4 camera stations operating continuously through the 2015 wetland construction, and for 2 years thereafter. The most common species captured in photos were White-tailed Deer, Wild Turkeys, ducks and geese, a variety of small bird species, and small mammals such as coyotes. Each trail camera took both motion-activated photos and timed photos (taken every 5 minutes regardless of animals present from sunrise to sunset). Motion-activated photos provide important insights into the activity patterns of larger animals, especially at night, whereas timed photos have allowed us to discern distinct seasonal patterns in the abundance of large flocks of potentially “hazardous” animals such as Canada Geese. Results thus far suggest that wildlife has flourished in the new wetland; we have documented 13 species of mammals and 27 species of birds, as well as a few reptiles and amphibians, through trail cam photos. In addition, the camera trap project has provided unique glimpses into the activity patterns of various species. Our wildlife census information has been used to advise wildlife management decisions, and can be used in the future to alert airport personnel to dates and times of potentially heightened risk

Role of Dietary Crocin in In Vivo Melanoma Tumor Remission

Background: Melanoma is a deadly form of malignancy. Early diagnosis might pave the way to cure but its aggressive nature leads to rapid dissemination and colonization of distant organs. Dietary herbs may play a significant role in prevention of cancer. In this study, we tested anti-tumor efficacy of the Crocus sativus derived active constituent crocin, it is well established to have anti-cancer properties in different cancer models by our group and other groups. Notably, crocin is reported to exert anti-proliferative effect on melanoma cells (B16F10) in vitro. However, roles of crocin on in vivo melanoma tumor remission have not yet been reported to our knowledge. Materials and Methods: Melanoma tumor model was established by transplanting B16F10 (5 X 105) cells into C57BL/6 mice, which were then observed for tumor development and once the tumor volume reached 6 mm, mice were divided into (Group I: tumor-bearing animals treated with normal saline and Group II: counterparts treated with crocin at 2 mg/kg body weight for 21 days). . Tumor remission and tumor growth related parameters such as tumor silent period (TSP), tumor volume doubling time (VDT), growth delay (GD), and mean survival time (MST) were determined. In addition, serum protein profiles were analyzed. Results: The 21 days crocin treatment significantly reduced the tumor burden in mice, extending the mean survival time significantly as compared to control. Crocin treatment also significantly increased the TGD and TSP and decreased VDT. Furthermore, while serum proteins such as albumin and globulin (alpha1, alpha2, beta, and gamma) were altered due to tumor burden, crocin treatment resulted in their levels near to normal at the end of the experimental period. Conclusion: Our study provided clear evidence that crocin may exhibit significant melanoma tumor remission properties by positively modulating tumor growth related parameters. In future, the molecular mechanisms of crocin action should be studied extensively in melanoma models before defining crocin-based melanoma drug formulation

Radiographers’ Acceptance on the Integration of Artificial Intelligence into Medical Imaging Practice

Artificial intelligence (AI) integration in medical imaging is a promising field for enhancing patient care, performance, and efficiency. Radiographers, on the other hand, are concerned about AI's acceptance and potential to replace them. This study assessed radiographers' acceptance of AI integration by considering their knowledge, attitudes, and job security. Based on demographic characteristics, there were no significant differences in knowledge, attitude, or job security level. Completing AI training, on the other hand, had a considerable influence.  Overall, radiographers have a good level of knowledge and are enthusiastic about using AI tools into their regular activities

Prefrontal cortical activation associated with prospective memory while walking around a real-world street environment

Rostral PFC (area 10) activation is common during prospective memory (PM) tasks. But it is not clear what mental processes these activations index. Three candidate explanations from cognitive neuroscience theory are: (i) monitoring of the environment; (ii) spontaneous intention retrieval; (iii) a combination of the two. These explanations make different predictions about the temporal and spatial patterns of activation that would be seen in rostral PFC in naturalistic settings. Accordingly, we plotted functional events in PFC using portable fNIRS while people were carrying out a PM task outside the lab and responding to cues when they were encountered, to decide between these explanations. Nineteen people were asked to walk around a street in London, U.K. and perform various tasks while also remembering to respond to prospective memory (PM) cues when they detected them. The prospective memory cues could be either social (involving greeting a person) or non-social (interacting with a parking meter) in nature. There were also a number of contrast conditions which allowed us to determine activation specifically related to the prospective memory components of the tasks. We found that maintaining both social and non-social intentions was associated with widespread activation within medial and right hemisphere rostral prefrontal cortex (BA 10), in agreement with numerous previous lab-based fMRI studies of prospective memory. In addition, increased activation was found within lateral prefrontal cortex (BA 45 and 46) when people were maintaining a social intention compared to a non-social one. The data were then subjected to a GLM-based method for automatic identification of functional events (AIDE), and the position of the participants at the time of the activation events were located on a map of the physical space. The results showed that the spatial and temporal distribution of these events was not random, but aggregated around areas in which the participants appeared to retrieve their future intentions (i.e., where they saw intentional cues), as well as where they executed them. Functional events were detected most frequently in BA 10 during the PM conditions compared to other regions and tasks. Mobile fNIRS can be used to measure higher cognitive functions of the prefrontal cortex in “real world” situations outside the laboratory in freely ambulant individuals. The addition of a “brain-first” approach to the data permits the experimenter to determine not only when haemodynamic changes occur, but also where the participant was when it happened. This can be extremely valuable when trying to link brain and cognition

Quantifying the Effects of Known Unknowns on Inferred High-redshift Galaxy Properties: Burstiness, the IMF, and Nebular Physics

The era of the James Webb Space Telescope ushers stellar populations models into uncharted territories, particularly at the high-redshift frontier. In a companion paper, we apply the \texttt{Prospector} Bayesian framework to jointly infer galaxy redshifts and stellar populations properties from broad-band photometry as part of the UNCOVER survey. Here we present a comprehensive error budget in spectral energy distribution (SED) modeling. Using a $z_{\rm phot}>9$ sample, we quantify the systematic shifts stemming from various model choices in inferred stellar mass, star formation rate (SFR), and age. These choices encompass different timescales for changes in the star formation history (SFH), non-universal stellar initial mass functions (IMF), and the inclusion of variable nebular abundances, gas density and ionizing photon budget. We find that the IMF exerts the strongest influence on the inferred properties: the systematic uncertainties can be as much as 1 dex, 2--5 times larger than the formal reported uncertainties in mass and SFR; and importantly, exceed the scatter seen when using different SED fitting codes. This means that a common practice in the literature of assessing uncertainties in SED-fitting processes by comparing multiple codes is substantively underestimating the true systematic uncertainty. Highly stochastic SFHs change the inferred SFH by much larger than the formal uncertainties, and introduce $\sim 0.8$ dex systematics in SFR and $\sim 0.3$ dex systematics in average age. Finally, employing a flexible nebular emission model causes $\sim 0.2$ dex systematic increase in mass, comparable to the formal uncertainty. This paper constitutes one of the initial steps toward a complete uncertainty estimate in SED modeling.Comment: Submitted to ApJ. 18 pages, 8 figures, 2 table

UNCOVER: Illuminating the Early Universe -- JWST/NIRSpec Confirmation of z>12z > 12 Galaxies

Observations of high-redshift galaxies provide a critical direct test to the theories of early galaxy formation, yet to date, only four have been spectroscopically confirmed at $z>12$. Due to strong gravitational lensing over a wide area, the galaxy cluster field Abell~2744 is ideal for searching for the earliest galaxies. Here we present JWST/NIRSpec observations of two galaxies: a robust detection at $z_{\rm spec} = 12.393^{+0.004}_{-0.001}$, and a plausible candidate at $z_{\rm spec} = 13.079^{+0.013}_{-0.001}$. The galaxies are discovered in JWST/NIRCam imaging and their distances are inferred with JWST/NIRSpec spectroscopy, all from the JWST Cycle 1 UNCOVER Treasury survey. Detailed stellar population modeling using JWST NIRCam and NIRSpec data corroborates the primeval characteristics of these galaxies: low mass ($\sim 10^8~{\rm M_\odot}$), young, rapidly-assembling, metal-poor, and star-forming. Interestingly, both galaxies are spatially resolved, having lensing-corrected rest-UV effective radii on the order of 300-400 pc, which are notably larger than other spectroscopically confirmed $z \gtrsim 12$ systems. The observed dynamic range of $z \gtrsim 12$ size spans over an order of magnitude, implying a significant scatter in the size-mass relation at early times. Deep into the epoch of reionization, these discoveries elucidate the emergence of the first galaxies.Comment: submitted to ApJL; 13 pages, 4 figures, 2 table