cssi/SciSciGPT-SciSciNet huggingface dataset:
Housing instability and child welfare: Examining the delivery of innovative services in the context of a randomized controlled trial

Abstract Child welfare-involved homeless families are at greater risk of poor social and economic outcomes compared with homeless families not involved with child welfare, and these negative outcomes reverberate in terms of economic and social costs to society. This study employed a mixed-methods approach to examine process findings from a randomized control trial from the first county-level Pay for Success initiative, Partnering for Family Success. The research compared housing, child welfare and public assistance outcomes for the treatment (N = 90) and control (N = 73) groups, explored how the program delivered its services, the service pattern over time, and perspectives of child welfare and program staff. We found that during and in the year after exiting the program, treatment group clients were less likely to use homeless services and were more likely to access public assistance benefits as compared with the control group clients, and during and after the program, the treatment and control group clients’ child maltreatment reports were not statistically significantly different. There were positive indications from quantitative data showing that the intervention patterns align with those of Critical Time Intervention (CTI), with qualitative interview data indicating shifts over time in case management focus from short-term crisis management and housing stability toward working on longer-term independent living skills. The findings contribute to the literature regarding how best to serve homeless, child welfare-involved families, and suggest the necessity for longer-term interventions and greater attention to non-housing-related needs.
T‐cells expressing a chimeric‐PD1‐Dap10‐CD3zeta receptor reduce tumour burden in multiple murine syngeneic models of solid cancer

Adoptive transfer of T-cells is a promising therapy for many cancers. To enhance tumour recognition by T-cells, chimeric antigen receptors (CARs) consisting of signalling domains fused to receptors that recognize tumour-associated antigens can be expressed in T-cells. While CAR T-cells have shown clinical success for treating haematopoietic malignancies, using CAR T-cells to treat solid tumours remains a challenge. We developed a chimeric PD1 (chPD1) receptor that recognizes the ligands for the PD1 receptor that are expressed on many types of solid cancer. To determine if this novel CAR could target a wide variety of tumour types, the anti-tumour efficacy of chPD1 T-cells against syngeneic murine models of melanoma, renal, pancreatic, liver, colon, breast, prostate and bladder cancer was measured. Of the 14 cell lines tested, all expressed PD1 ligands on their cell surface, making them potential targets for chPD1 T-cells. ChPD1 T-cells lysed the tumour cells and secreted pro-inflammatory cytokines [interferon (IFN)γ, tumour necrosis factor (TNF)α, interleukin (IL)-2, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-17 and IL-21], but did not secrete the anti-inflammatory cytokine IL-10. Furthermore, T-cells expressing chPD1 receptors reduced an established tumour burden and led to long-term tumour-free survival in all types of solid tumours tested. ChPD1 T-cells did not survive longer than 14 days in vivo; however, treatment with chPD1 T-cells induced protective host anti-tumour memory responses in tumour-bearing mice. Therefore, adoptive transfer of chPD1 T-cells could be a novel therapeutic strategy to treat multiple types of solid cancer.
Movers and Stayers: What Birthplaces Can Teach Us About Rural Practice Choice Among Midwestern General Surgeons.

PURPOSE This study compares practicing rural Midwestern general surgeons born in urban areas to those born in rural areas to describe the association between birthplace and current practice location. METHODS The 2017 AMA MasterFile was used to study general surgeons in the Midwest Census Division. Surgeons were assigned to categories based on birthplace and current practice locations: urban-urban stayers, urban-rural movers, rural-rural stayers, and rural-urban movers. Urban and rural classifications corresponded to the metropolitan and nonmetropolitan definitions with Rural-Urban Continuum Codes (urban, RUCCs 1-3; rural, RUCCs 4-9). Bivariate tests and logistic regression were used to determine factors associated with rural practice choice. FINDINGS There were 3,070 general surgeons in the study population: 70.6% urban-urban stayers, 13.1% urban-rural movers, 10.7% rural-urban movers, and 5.7% rural-rural stayers. Rural areas netted 74 surgeons (327 rural-urban movers versus 401 urban-rural movers). Logistic regression results found different factors predicted rural practice among urban-born versus rural-born surgeons. Older urban-born surgeons were more likely to practice rurally, as were male surgeons, DOs, and those trained in less-urban residency programs. Among rural-born surgeons, more rural birthplaces and having trained at a less-urban residency were associated with practicing rurally. CONCLUSIONS Recruiting urban-born surgeons to rural areas has proven successful in the Midwest; our findings show urban-born surgeons outnumber rural-born surgeons in rural communities. Given the ongoing need for surgeons in rural areas, urban-born surgeons should not be overlooked. Findings suggest educators and community leaders should expand less-urban training opportunities given their potential influence on all general surgeons.
A Study to Evaluate the Need for Comminution in the Preparation of Food Materials for Testing of Listeria monocytogenes, Staphylococcus Species, and Generic Escherichia coli.

BACKGROUND Comminution reduces the sampling error arising from distributional heterogeneity of the target contaminant/target analyte in the material, facilitating the selection of a more representative test portion. A laboratory sampling method incorporating comminution prior to selection of the test portion (Sampling Method B) was compared to current sampling methods that used no comminution step (Sampling Method A). OBJECTIVE This required the development of an efficient process for comminution of food samples prior to removal of the test portion for the detection and isolation of Listeria monocytogenes and the enumeration of Staphylococcus species and Escherichia coli. METHOD From December 2016 to December 2017, 2742 tests were conducted on 778 unique food samples. For all food samples, a test portion (TPA) was first removed using Sampling Method A, and then the remainder of the material was comminuted and a second test portion (TPB) was removed using Sampling Method B and tested alongside the first portion. RESULTS Across all food matrices and microbial targets, 17 additional targets were detected using only Sampling Method B, and positive detections of target analytes increased by 77% using Sampling Method B from the test portions taken using Sampling Method A. CONCLUSION Utilizing a sample preparation method that includes a comminution step resulted in an increased number of pathogen detections. HIGHLIGHTS The introduction of a comminution step in the preparation of food samples for detection of three common microbial contaminants resulted in an increase in the rate of detection of natural contaminates in a variety of ready to eat foods. An efficient aseptic process for commutation that can be adapted to a wide range of laboratory settings was identified.
Structural Insights into RNA Dimerization: Motifs, Interfaces and Functions

In comparison with the pervasive use of protein dimers and multimers in all domains of life, functional RNA oligomers have so far rarely been observed in nature. Their diminished occurrence contrasts starkly with the robust intrinsic potential of RNA to multimerize through long-range base-pairing ("kissing") interactions, self-annealing of palindromic or complementary sequences, and stable tertiary contact motifs, such as the GNRA tetraloop-receptors. To explore the general mechanics of RNA dimerization, we performed a meta-analysis of a collection of exemplary RNA homodimer structures consisting of viral genomic elements, ribozymes, riboswitches, etc., encompassing both functional and fortuitous dimers. Globally, we found that domain-swapped dimers and antiparallel, head-to-tail arrangements are predominant architectural themes. Locally, we observed that the same structural motifs, interfaces and forces that enable tertiary RNA folding also drive their higher-order assemblies. These feature prominently long-range kissing loops, pseudoknots, reciprocal base intercalations and A-minor interactions. We postulate that the scarcity of functional RNA multimers and limited diversity in multimerization motifs may reflect evolutionary constraints imposed by host antiviral immune surveillance and stress sensing. A deepening mechanistic understanding of RNA multimerization is expected to facilitate investigations into RNA and RNP assemblies, condensates, and granules and enable their potential therapeutical targeting.
The Glossopharyngo-Cochlear Triangle-Part I: Quantitative Anatomic Analysis of High-Riding Posterior Inferior Cerebellar Artery Aneurysms Exposed Through the Extended Retrosigmoid Approach.

Background An extended retrosigmoid approach can offer sufficient space for clip reconstruction of some high-riding posterior inferior cerebellar artery (PICA) aneurysms. Objective To quantitatively investigate the glossopharyngo-cochlear triangle (GCT) and anatomic structures within it. Methods Extended retrosigmoid craniotomies were performed on 10 sides of cadaveric heads, and the GCT was identified in each specimen. The length of the base and the area of the GCT were measured. The depth of the vertebrobasilar system and the abducens nerve to the GCT were measured. The proximal and distal exposable and controllable points on the vertebrobasilar system were identified. Two imaging-based patient selection algorithms are provided using the lengths from those points to the vertebral artery dural entry point and the superoinferior distances from those points to the inferior edge of the foramen magnum. Other factors related to accessibility via the GCT were investigated. Results The mean (standard deviation [SD]) area of the GCT was 45.7 (12.55) mm2. The mean (SD) depth of the abducens nerve was 14.3 (1.42) mm. The mean (SD) superoinferior distances from the foramen magnum to those points were 23.1 (7.39), 24.7 (8.25), 30.0 (9.56), and 32.6 (7.79) mm, respectively. The lower segment of the vertebrobasilar system was more superficial in the setting of a high-lying vertebrobasilar junction (VBJ) than a low-lying VBJ. Conclusion We describe the GCT in an extended retrosigmoid approach for high-riding PICA aneurysms and evaluate the spatial relationship of the neurovascular structures within it. Two potential algorithms are offered for preoperative patient selection.
Have Fun Storming the Castle(s)

In recent years, large-scale datasets, each typically tailored to a particular problem, have become a critical factor towards fueling rapid progress in the field of computer vision. This paper describes a valuable new dataset that should accelerate research efforts on problems such as fine-grained classification, instance recognition and retrieval, and geolocalization. The dataset, comprised of more than 2400 individual castles, palaces and fortresses from more than 90 countries, contains more than 770K images in total. This paper details the dataset’s construction process, the characteristics including annotations such as location (geotagged latlong and country label), construction date, Google Maps link and estimated per-class and per-image difficulty. An experimental section provides baseline experiments for important vision tasks including classification, instance retrieval and geolocalization (estimating global location from an image’s visual appearance). The dataset is publicly available at vision.cs.byu.edu/castles.
Real Tissue Robotic Simulation: The KindHeart Simulators

Simulation-based training has been shown to be a very effective means of imparting robotic surgery skills necessary prior to engaging in clinical work. These simulators take anatomically appropriate animal tissue, preserve it for extending periods of time in a preserving solution at 4 °centigrade, reanimate it to act like live tissue, and place it in humanoid mannequins. These simulators (KindHeart Inc.) provide an experience that is complimentary to computerized virtual reality simulation by giving the surgeon an animal tissue experience without the need for live animals and providing a more comfortable bridge to clinical work. Real tissue simulators now exist for basic skills, abdominal wall and inguinal hernias, colon resection, thoracic surgery, cardiac surgery, bariatric surgery, foregut anti-reflux surgery, and pelvic surgery. Full robotic surgery training curricula continue to be developed and provide for training not only in traditional robotic procedures but new robotic procedures and the proper handling of adverse events should they occur.
Medical Necessity Indications & Impact On Management: Fourth and Subsequent Post-therapy Follow-up FDG-PET/CT Scans in Oncology Patients

414 Objectives In the follow-up of oncology patients, the Centers for Medicare and Medicaid Services (CMS) announced to cover only three post-therapy FDG-PET/CT scans per patient and per tumor type. Any additional follow-up FDG-PET/CT will be covered only at the discretion of a local Medicare administrator, justified by medical necessity. This study aims to investigate the common medical necessity indications for fourth and more follow-up FDG-PE/CT. The impacts of each fourth and subsequent FDG-PET/CT in the management of patients were also determined. Methods In this retrospective institutional review, 315 oncology patients (134 male, mean age 57 years) with a total of 1,283 fourth or subsequent follow-up PET/CT scans after completion of primary treatment were included. Results Overall, fourth and subsequent follow-up FDG-PET/CT resulted in a change in therapy management in 299 scans (23.3%), justify continuing the same treatment regimen in 435 scans (33.9%), and no change in treatments in 501 scans (39.1%). The impact on management is unknown in 48 of scans (3.7%). The percentage change in the management is 6.7% (25 out of 374) when the scans were performed without any medical necessity (indication 11) and 30.1% (274 out of 909), when performed with medical necessity (indication 1-10). Conclusions The fourth and subsequent FDG-PET/CT scans performed after completion of primary treatment lead to change in management in 6.7% when scans were performed without any medical necessity and 30.1% when performed with medical necessity. Hence, performing follow up PET/CT without medical necessity should be avoided in clinical practice for value added health care delivery.
Intermittent and Transient Hypotension-related Anterior Cord Syndrome following Elective Cervical Spine Surgery: A Case Report.

Introduction Anterior cord syndrome (ACS) is a type of incomplete spinal cord injury caused by either direct compression of the anterior spinal cord, or by ischemia of the anterior spinal artery. This phenomenon has neither been described transiently nor intraoperatively. Case Report We describe the case of a 61-year-old male who developed intermittent and transient anterior spinal cord syndrome secondary to hypotension related hypoperfusion of the anterior spinal artery after elective cervical spine surgery. Through close blood pressure monitoring and intensive care unit support, the patient regained full neurological recovery. Conclusion Anterior spinal cord syndrome is a rare condition affecting the anterior 2/3 of the spinal cord, resulting in incomplete paralysis. Blood flow can be disrupted through the anterior spinal artery, either through thrombosis or hypotension. We describe our rare case so that surgeons may recognize this potentially devastating condition.
Sustainability analysis of ecological systems in fire prone areas using the concept of Sustainability over Sets (SOS)

The dynamic coexistence of trees and grass is a vital component for a sustainable ecological system. This dynamical coexistence could be affected through continuous and alternate natural perturbations such as herbivore grazing, wildfires, droughts, and human activities. To fully understand the dynamics and sustainability of such ecological systems, first rigorous mathematical models need to be developed, capturing the systems' behavior, and subsequently, tools are created to analyze their sustainability. With this goal in mind, two concepts of Sustainability over Sets (SOS) and Sustainizability over Sets (SIZOS) have been recently introduced as sustainable system analysis and synthesis tools, respectively, with broad flexibility in incorporating human input. In this work, the SOS concept is first briefly introduced and afterward applied to a dynamical system consisting of tree grass components under different wildfire frequencies. The obtained results show that an increase in wildfire frequency will result in a system only consisting of grassland and thus the ecosystem is deemed unsustainable.
College esl students' attitudes and beliefs about computer-assisted writing classes

The purpose of this study was to examine the attitudes and beliefs of a group of basic level college writing ESL students about a computer-aided composition class. Specifically, it sought to focus on their beliefs and attitudes regarding their writing development through the extensive use of the Web-based CMS, WebCT. In addition, the study reports on ESL students' perceptions on the obstacles and difficulties they experienced when learning composition in a computer-aided writing course (CAWC) environment. Thirteen ESL students enrolled in an introductory writing course participated in this qualitative/quantitative study. Data from student diaries revealed that students enjoyed and valued the WebCT course. Student diary entries reported that the use of computers and WebCT facilitated their acquisition of writing skills and that students valued instructor feedback and peer responses to their work. Classroom observations yielded information about the structure of the class and instructor activities including the success of repetition of key ideas and brainstorming about topics in class. Interviews with the students revealed that students thought that computers made the acquisition of writing skills easier and faster, and students valued the feedback from instructors and fellow classmates alike. Quantitative survey results indicated that almost none of the students had previously taken a WebCT course, and that the use of WebCT in the course made the students become better writers. With regard to attitudes about writing, students responded that computers made writing easier, made them learn to write better, and did not take more time than traditional writing. Hypothesis tests indicated (a) that student attitudes about the use of WebCT were related to the grades they earned in the class, (b) that attitudes about the effectiveness of WebCT were related to course activity, (c) that there was no relationship between years of computer use and attitudes about the effectiveness of WebCT, and (d) that there was no relationship between prior computer knowledge and attitudes about WebCT.
Terahertz Electric Field Imaging

Various frequencies are spaced along the frequently used electromagnetic spectrum, including microwaves, infrared, visible light, and X rays. Terahertz radiation between microwave and infrared frequencies lies. In the electromagnetic spectrum, radiation at 1 THz has a period of 1 ps, a wavelength of 300 µm, a wave number of 33 cm−1, photon energy of 4.1 meV, and an equivalent temperature of 47.6 K. In the same way that visible light can create a photograph, radio waves can transmit sound, and X rays can see shapes within the human body, terahertz waves (Trays) can create pictures and transmit information. Until recently, however, the very large terahertz portion of the spectrum has not been particularly useful because there were neither suitable emitters to send out controlled terahertz signals nor efficient sensors to collect them and record information. Recent developments in terahertz time-domain spectroscopy and related terahertz technologies now lead one to view the world in a new way. As a result of developing research, terahertz radiation now has widespread potential applications in medicine, microelectronics, agriculture, forensic science, and many other fields. Three properties of THz wave radiation triggered research to develop this frequency band for applications and are discussed. Coherent terahertz time-domain spectroscopy that has an ultrawide bandwidth provides a new method for characterizing the electronic, vibronic, and compositional properties of solid, liquid, and gas phase materials, as well as flames and flows. In theory, many biological and chemical compounds have distinct signature responses to terahertz waves due to their unique molecular vibrations and rotational energy levels, this implies that their chemical compositions might be examined using a terahertz beam. A T-ray imaging modality would produce images that have “component contrast” enabling analysis of the water content and composition of tissues in biological samples. Such capability presents tremendous potential to identify early changes in composition and function as a precursor to specific medical investigations and treatment. Moreover, in conventional optical transillumination techniques that use near-infrared pulses, large amounts of scattering can spatially smear out the objects to be imaged. T-ray imaging techniques, due to their longer wavelengths, can provide significantly enhanced contrast as a result of low scattering (Rayleigh scattering). Keywords: terahertz wave; generation of beams; free space electro-optic detectors; electro-optic measurement; chirped probe pulse; terahertz imaging
Resource allocation and QoS in mobile ad hoc networks

Quality of Service support in MANET is a challenging and difficult due to the dynamic nature of the ad hoc network, nodes may leave, and join the network or move around at anytime. In order to support certain level of service quality, a mechanism for recourses allocations/reservation has to be implemented to provide the needed assurance for the desired level of quality.However, in such a mobile environment (unlike networks with fixed topology), no service guarantee can be assured by any reservation/allocation mechanism and all what those mechanisms can offer is a better chance or a promise for better service. Several mechanisms have been developed, they differ in the level of assurance they can provide ranging from no assurance to relatively high level of assurance.In this paper, we present a survey of the current research that has developed to address the problem. Some of those mechanisms are, DiffServ, DSRRSVP, DRSVP and MRSVP. We also compare them based on certain criteria (complexity, scalability, level of assurance, control overhead, and types of environments that they support).
A proposal of LDMOS using Deep Trench poly field plate

In this paper, we developed Deep Trench structure of LDMOS instead of STI in conventional one, with 0.18um 60V BCD process. By forming vertical drift region using Deep Trench, we achieved lower Ron.sp from cell pitch shrink while BVdss does not change. As a result we achieved 76V BVdss and 49.3 mohm∗mm2 Ron.sp of low side 60V rated LDNMOS.
A new solid-state reagent to iodinate proteins. I. Conditions for the efficient labeling of antiserum.

Abstract A new solid-state reagent for iodinating polypeptides and proteins was used to radiolabel antiporcine insulin antiserum. Reaction conditions of pH, temperature, buffer, reactant concentration, and the type of reaction vessel were optimized to achieve almost quantitative incorporation of radioiodide (99%), good recovery of protein (92%), and a moderate specific activity (9.9 μCi/μg of antiserum). A second set of conditions was found to produce antiserum of high specific activity (161 μCi/μg) which retained its immunological ability to recognize insulin. The nature of the actual iodinating species and the effects on the reaction of sodium azide, detergents, and chaotropic reagents such as urea and high salt were investigated.
Sparse data and the effect of overfitting avoidance in decision tree induction

Overfitting avoidance in induction has often been treated as if it statistically increases expected predictive accuracy. In fact, there is no statistical basis for believing it will have this effect. Overfitting avoidance is simply a form of bias and, as such, its effect on expected accuracy depends, not on statistics, but on the degree to which this bias is appropriate to a problem-generating domain. This paper identifies one important factor that affects the degree to which the bias of overfitting avoidance is appropriate--the abundance of training data relative to the complexity of the relationship to be induced--and shows empirically how it determines whether such methods as pessimistic and cross-validated cost-complexity pruning will increase or decrease predictive accuracy in decision tree induction. The effect of sparse data is illustrated first in an artificial domain and then in more realistic examples drawn from the UCI machine learning database repository.
Assessing controls on diffuse groundwater recharge using unsaturated flow modeling

[1] Understanding climate, vegetation, and soil controls on recharge is essential for estimating potential impacts of climate variability and land use/land cover change on recharge. Recharge controls were evaluated by simulating drainage in 5-m-thick profiles using a one-dimensional (1-D) unsaturated flow code (UNSAT-H), climate data, and vegetation and soil coverages from online sources. Soil hydraulic properties were estimated from STATSGO/SSURGO soils data using pedotransfer functions. Vegetation parameters were obtained from the literature. Long-term (1961–1990) simulations were conducted for 13 county-scale regions representing arid to humid climates and different vegetation and soil types, using data for Texas. Areally averaged recharge rates are most appropriate for water resources; therefore Geographic Information Systems were used to determine spatial weighting of recharge results from 1-D models for the combination of vegetation and soils in each region. Simulated 30-year mean annual recharge in bare sand is high (51–709 mm/yr) and represents 23–60% (arid–humid) of mean annual precipitation (MAP). Adding vegetation reduced recharge by factors of 2–30 (humid–arid), and soil textural variability reduced recharge by factors of 2–11 relative to recharge in bare sand. Vegetation and soil textural variability both resulted in a large range of recharge rates within each region; however, spatially weighted, long-term recharge rates were much less variable and were positively correlated with MAP (r2 = 0.85 for vegetated sand; r2 = 0.62 for variably textured soils). The most realistic simulations included vegetation and variably textured soils, which resulted in recharge rates from 0.2 to 118 mm/yr (0.1–10% of MAP). Mean annual precipitation explains 80% of the variation in recharge and can be used to map recharge.
Postcolonial Borderlands: Black Life Worlds and Relational Place in Turin, Italy

The emergence of Italy as a receiving country of postcolonial immigrants from all over Africa and other parts of the economically developing world involves the reproduction of deeply rooted prejudices and colonial legacies expressed in territorial concepts of belonging. Yet geographical discussions of borders seldom begin their explorations from the vantage point of what Hanchard has called, “Black life worlds”, complex experiences of place among African diasporic populations in relationship to race. This paper examines situated practices, negotiations, and meanings of place, identity and belonging among first generation African-Italians in Northern Italy whose experiences suggest that the borders between Africa and Europe are far more porous than they appear to be. This essay develops a theory of relational place to study the meaning of place in Black life worlds as indexed by the everyday materiality of bodies in relation to racial discourses and practices, and the profound interweavings of Africa and Europe through space and time. The essay examines African-Italo experiences in relation to the transformation of political culture in Turin, the rise of ethno-nationalism, and legacies of Italian colonialism.
Reaction of excited chlorophyll molecules at electrodes and in photosynthesis.

Abstract— Excited molecules can exchange electrons with suitable electrodes in an electrochemical cell. Excitation energy of molecules can therefore be converted into electrochemical energy. Electrochemical reactions of excited chlorophyll molecules have been investigated with the help of semiconductor electrodes. It is suggested that this type of reaction also occurs during the primary steps of photosynthesis. Consequently, concepts of electrochemical kinetics would have to be applied in order to elucidate chlorophyll-sensitized reactions in photosynthetic membranes. In order to provide evidence for this conclusion, electrochemical kinetics is applied to the calculation of decay of delayed light from photosynthetic membranes, and the result is compared with experimental data from Chlorella pyrenoidosa. The conversion of light into electrochemical energy via photoelectrochemical reactions of organic dyes in an electrochemical cell is demonstrated, and the postulated analogous electrochemical mechanism for photosynthesis is discussed.
Comparison of density functional calculations of CNO2, NNO2 and CNF2 dissociation energies

Abstract We compare the effectiveness of three exchange/correlation functional combinations (Becke/Lee, Yang and Parr; Becke-3/Lee, Yang and Parr; Becke-3/Perdew-Wang 91) for computing CNO 2 , NNO 2 and CNF 2 bond lengths and dissociation energies. The Becke-3/Perdew-Wang 91 is found to give the best results, although for CNF 2 bonds the differences are less important than for CNO 2 and NNO 2 . The presence of NO 2 and NF 2 on the same carbon considerably weakens the bond to each.
One-Electron Oxidation of Individual DNA Bases and DNA Base Stacks

In calculations performed with DFT there is a tendency of the purine cation to be delocalized over several bases in the stack. Attempts have been made to see if methods other than DFT can be used to calculate localized cations in stacks of purines, and to relate the calculated hyperfine couplings with known experimental results. To calculate reliable hyperfine couplings it is necessary to have an adequate description of spin polarization which means that electron correlation must be treated properly. UMP2 theory has been shown to be unreliable in estimating spin densities due to overestimates of the doubles correction. Therefore attempts have been made to use quadratic configuration interaction (UQCISD) methods to treat electron correlation. Calculations on the individual DNA bases are presented to show that with UQCISD methods it is possible to calculate hyperfine couplings in good agreement with the experimental results. However these UQCISD calculations are far more time-consuming than DFT calculations. Calculations are then extended to two stacked guanine bases. Preliminary calculations with UMP2 or UQCISD theory on two stacked guanines lead to a cation localized on a single guanine base.
Identification of proximate regions in a complex of retinal guanylyl cyclase 1 and guanylyl cyclase-activating protein-1 by a novel mass spectrometry-based method.

Abstract A key challenge in studying protein/protein interactions is to accurately identify contact surfaces,i.e. regions of two proteins that are in direct physical contact. Aside from x-ray crystallography and NMR spectroscopy few methods are available that address this problem. Although x-ray crystallography often provides detailed information about contact surfaces, it is limited to situations when a co-crystal of proteins is available. NMR circumvents this requirement but is limited to small protein complexes. Other methods, for instance protection from proteolysis, are less direct and therefore less informative. Here we describe a new method that identifies candidate contact surfaces in protein complexes. The complexes are first stabilized by cross-linking. They are then digested with a protease, and the cross-linked fragments are analyzed by mass spectrometry. We applied this method, referred to as COSUMAS (contact surfaces bymass spectrometry), to two proteins, retinal guanylyl cyclase 1 (RetGC1) and guanylyl cyclase-activating protein-1 (GCAP-1), that regulate cGMP synthesis in photoreceptors. Two regions in GCAP-1 and three in RetGC1 were identified as possible contact sites. The two regions of RetGC1 that are in the vicinities of Cys741 and Cys780 map to a kinase homology domain in RetGC1. Their identities as contact sites were independently evaluated by peptide inhibition analysis. Peptides with sequences from these regions block GCAP-1-mediated regulation of guanylyl cyclase at both high and low Ca2+ concentrations. The two regions of GCAP-1 cross-linked to these peptides were in the vicinities of Cys17 and Cys105 of GCAP-1. Peptides with sequences derived from these regions inhibit guanylyl cyclase activity directly. These results support a model in which GCAP-1 binds constitutively to RetGC1 and regulates cyclase activity by structural changes caused by the binding or dissociation of Ca2+.
Caffeine-induced stimulus control

Abstract Six rats were trained to discriminate the effects of caffeine (60 mg/kg, pretreatment time: 1 hour) and saline in a two-lever choice task using a fixed ratio 10 schedule of water reinforcement. Stimulus control was assumed to be present when 80% or more of the first ten responses were appropriate for the treatment condition on each of five consecutive days. The mean number of sessions prior to the onset of criterion performance was 22 (SE = 3; range = 11−32). In trained subjects, doses of caffeine of 30, 10, and 3 mg/kg were followed by a progressively smaller proportion of responses on the caffeine-appropriate lever. Stimulus control by caffeine began to diminish about four hours after administration and was completely absent after 24 hours. The caffeine cue generalized partially to d-amphetamine and completely to aminophylline. Neither pizotyline nor spiperone antagonized stimulus control induced by caffeine.
Dual resonance model incorporating two different parent Regge trajectories in the same channel

A four-particle dual model is constructed with two different Regge trajectories in both the s and t channels. The amplitude is crossing-symmetric, has residues that are polynomial of correct order, and has full Regge behavior. In a certain limit it becomes the Euler B function. The multiparticle generalization of the present model will be relevant to construction of hadron models with realistic mass spectra. (AIP)
Variations of the Mid-Infrared Emission Spectrum in Reflection Nebulae*

Using spatial-spectral data cubes of reflection nebulae obtained by ISOCAM, we have observed a shift in the central wavelength of the 7.7 μm band within several reflection nebulae. This band, composed of components at 7.85 and 7.65 μm, shows a centroid shift from 7.75 μm near the edge of the nebulae to 7.65 μm toward the center of the nebulae as the shorter wavelength component becomes relatively stronger. The behavior of the 7.7 μm band center can be explained by assuming either that anions are the origin of the 7.85 μm band and cations the 7.65 μm band, or that the band center wavelength depends on the chemical nature of the polycyclic aromatic hydrocarbons (PAHs). The ratio of the 11.3/7.7 μm bands also changes with distance from the central star, first rising from the center toward the edge of the nebula, then falling at the largest distances from the star, consistent with the 11.3/7.7 μm band ratio being controlled by the PAH ionization state.
Neighborhood Effects Research: New Perspectives

Neighborhood Effects Research: New Perspectives. 2012. Edited by MAARTEN VAN HAM, DAVID MANLEY, NICK BAILEY, LUDI SIMPSON, and DUNCAN MACLENNAN. Dordrecht: Springer. Pp. xii + 297. £90.00 or US$139...
Cultivating the next generation of international digital government researchers: a community-building experiment

Over the last two decades universities and post-secondary education policies have addressed globalization trends by internationalizing curricula and articulating global concern in their missions. This paper presents the evaluation of an international training program for early-career digital government researchers, designed to develop their interest and skill in cross-cultural, multidisciplinary, and practice-oriented research. The program overall appears to stimulate participants' individual creativity, scholarly productivity, and professional networks, while broadening their appreciation for work that investigates internationally important topics and involves not only multidisciplinary but multicultural teams. The survey results also suggest that a short-term (one-week), intensive, immersive, and relatively inexpensive program can have strong and lasting effects on early-career scholars.
Lens α-crystallin and hypericin: A photophysical mechanism explains observed lens damage

Determining whether alpha-crystallin (the major lens protein) affects the photophysics of hypericin, a photosensitizing agent found in various plants, such as St. John's Wort, is important. Hypericin shows promise in cancer and human immunodeficiency virus therapy but may harm individuals taking St. John's Wort extracts (for mild to moderate depression). Hypericin causes hypericism, which is characterized by cellular damage in light-exposed areas. Ocular tissues are at risk for photosensitized damage; thus, we investigated the effects on hypericin photophysics by alpha-crystallin. We measured the transient absorption spectra and the 1270 nm luminescence of singlet (1Deltag) oxygen produced from hypericin in the presence of alpha-crystallin. alpha-Crystallin complexes hypericin, extending the lifetime of its triplet excited state; the Stern-Volmer slope is negative, but not linear, after a saturation curve. Damage to the lens protein by hypericin is known to occur via singlet oxygen, which oxidizes methionine, tryptophan and histidine residues. Binding to alpha-crystallin does not inhibit singlet oxygen formation by hypericin. alpha-Crystallin reacts with singlet oxygen with a rate constant of 1.3 x 10(8) M(-1) s(-1). Thus, we anticipate that hypericin will be an effective photosensitizer in the lens.
Increased tibiofemoral cartilage contact deformation in patients with anterior cruciate ligament deficiency.

Objective To investigate the in-vivo cartilage contact biomechanics of the tibiofemoral joint following anterior cruciate ligament (ACL) injury.
Relation of particle size of colloidal silica to the amount of a cationic polymer required for flocculation and surface coverage

Abstract This is a study of the flocculation of colloidal silicas of known uniform particle sizes by a quaternary ammonium substituted methacrylate polymer, of which the cations are adsorbed on the anionic sites of the silica surface by ion exchange. The unusual observation is reported that as increasing amounts of polymer are added to a silica sol of a given particle size, all of the polymer is precipitated, carrying down with it a constant ratio of silica to polymer. When sufficient polymer has been added to precipitate all of the silica, further amounts of polymer are then adsorbed on the precipitate until the silica surface is saturated, after which free polymer remains in solution. For particles smaller than 40 nm, the amount of polymer required to precipitate 1 unit weight of silica varies inversely with particle diameter; for larger silica particles, it varies inversely with the square of the diameter. These different relationships are consistent with calculations based on two models: (1) With particles smaller than 40 nm diameter, only a segment of a polymer chain, which is 150 nm long, is required to bridge one pair of particles; thus a single chain can extend through the bridging points of several pairs of particles. (2) With larger particles, one or more polymer chains are required to form the bridge at one contact point between a single pair of particles. A new spot test technique for detecting either excess silica or polymer in the supernatant liquid is employed, based on adsorption of a monolayer on a black glass test plate, and making its presence or absence visible by the interference color developed by a subsequently applied monolayer of 150 nm silica particles.
Integer-Valued Polynomials over Matrix Rings

When D is a commutative integral domain with field of fractions K, the ring Int(D) = {f ∈ K[x] | f(D) ⊆ D} of integer-valued polynomials over D is well-understood. This article considers the construction of integer-valued polynomials over matrix rings with entries in an integral domain. Given an integral domain D with field of fractions K, we define Int(M n (D)): = {f ∈ M n (K)[x] | f(M n (D)) ⊆ M n (D)}. We prove that Int(M n (D)) is a ring and investigate its structure and ideals. We also derive a generating set for Int(M n (ℤ)) and prove that Int(M n (ℤ)) is non-Noetherian.
Determination of the optical purity of timolol maleate by proton nuclear magnetic resonance spectroscopy with a chiral Pr(III) shift reagent

Abstract A 1 H NMR spectroscopic method with chiral shift chelate is presented for the determination of the optical purity of timolol maleate. Optimum experimental conditions were established by studying the interactions of solvents (CCl 4 , CDCl 3 ), substrate concentration, and the type and concentration of chiral lanthanide chelate (Pr(hfc) 3 , Eu(hfc) 3 ). Larger induced shift (Δδ) and enantiomeric shift difference (ΔΔδ) values, and more detailed spectral differences were obtained with Pr(hfc) 3 than with Eu(hfc) 3 . By monitoring the spectral changes of the resonance signals for the enantiomeric -C(CH 3 ) 3 protons, suitable conditions for quantitative determinations were found when 0.1 molar equivalents of Pr(hfc) 3 were complexed with 0.074 M of substrate. Enantiomeric compositions were calculated from the relative intensities of the enantiomeric -C(CH 3 ) 3 proton resonances. Based on the analysis of six synthetic enantiomeric mixtures, the mean ± SD recovery of ( R )-(+)-timolol by the proposed method was 99.5 ± 1.17% of the amount added.
Trend‐Surface Analysis of Ground‐Water Fluctuationsa

As round-water research is accelerated and basic data on aquifer parameters become more abundant, a statistical approach to evaluation of the ground-water regimen becomes increasingly useful. One such statistical technique is the fitting of polynomial trend-surfaces to ground-water levels. Barcholomew County, Indiana was chosen as a test site to derive techniques which could give additional guidance in the selection of areas suitable for the development of future ground-water resources. Trend-surface maps and maps of the deviations from the trend-surfaces were prepared from water-level data and evaluated to establish their relationships with the hydrogeologic regimen. A field-testing program was carried out to evaluate aquifer parameters. On the basis of the results obtained from these studies, the following conclusions were drawn: 1 A mathematically fitted surface may be considered to approximate the water-table or piezomecric surface, and will be sensitive to fluctuations in the ground-water reservoir. 2 The anomalous areas of the trend-surface represent local effects superimposed on the regional base and may be explained by a particular set of geologic, hydrologie or man-made conditions. From these conclusions, it appears that trend-surface analysis provides a rapid, inexpensive method of delineating attractive areas for detailed ground-water investigations.
QUANTUM HALL QUARKS OR SHORT DISTANCE PHYSICS OF FRACTIONALLY QUANTIZED HALL FLUIDS

In order to obtain a local description of the short distance physics of fractionally quantized Hall states for realistic (e.g. Coulomb) interactions, I propose to view the zeros of the ground state wave function, as seen by an individual test electron from far away, as particles. I then present evidence in support of this interpretation, and argue that the electron effectively decomposes into quarklike constituent particles of fractional charge.
Can diversifying selection be distinguished from history in geographic clines? A population genomic study of killifish (Fundulus heteroclitus).

A common geographical pattern of genetic variation is the one-dimensional cline. Clines may be maintained by diversifying selection across a geographical gradient but can also reflect historical processes such as allopatry followed by secondary contact. To identify loci that may be undergoing diversifying selection, we examined the distribution of geographical variation patterns across the range of the killifish (Fundulus heteroclitus) in 310 loci, including microsatellites, allozymes, and single nucleotide polymorphisms. We employed two approaches to detect loci under strong diversifying selection. First, we developed an automated method to identify clinal variation on a per-locus basis and examined the distribution of clines to detect those that exhibited signifcantly steeper slopes. Second, we employed a classic -outlier method as a complementary approach. We also assessed performance of these techniques using simulations. Overall, latitudinal clines were detected in nearly half of all loci genotyped (i.e., all eight microsatellite loci, 12 of 16 allozyme loci and 44% of the 285 SNPs). With the exception of few outlier loci (notably mtDNA and malate dehydrogenase), the positions and slopes of Fundulus clines were statistically indistinguishable. The high frequency of latitudinal clines across the genome indicates that secondary contact plays a central role in the historical demography of this species. Our simulation results indicate that accurately detecting diversifying selection using genome scans is extremely difficult in species with a strong signal of secondary contact; neutral evolution under this history produces clines as steep as those expected under selection. Based on these results, we propose that demographic history can explain all clinal patterns observed in F. heteroclitus without invoking natural selection to either establish or maintain the pattern we observe today.
Radiographic screen-film noise power spectrum: calibration and intercomparison.

The magnitude of a measurement of the noise power spectrum (NPS) of a radiographic screen-film system is affected by the light-scattering properties of the film studied and the optical characteristics of the microdensitometer used to sample the image. To facilitate absolute NPS intercomparisons among laboratories, NPS in terms of instrument density must be converted to diffuse density. Conversion in terms of a Callier Q factor was found to be inadequate due to nonlinearity of the density response of the microdensitometer. By establishing instrument-to-diffuse density characteristic curves for the microdensitometers at two laboratories and correcting the NPS by the square of the slopes of these curves at the density of the image, good agreement was achieved for independent NPS measurements of a given film sample.