cssi/SciSciGPT-SciSciNet huggingface dataset:
V2V-based Synchronous Intersection Protocols for Mixed Traffic of Human-Driven and Self-Driving Vehicles

Self-driving vehicles are expected to be at the core of future transportation systems. Over time, these vehicles might enhance traffic efficiency and safety, especially at road intersections. However, there will likely be a long transition period before human-driven vehicles will be completely replaced by automated vehicles. Intersection safety and efficiency might be barely improved if automated vehicles just follow the traffic light signals. In this paper, we present a decentralized intersection protocol named the Distributed Synchronous Intersection Protocol (DSIP) that is for mixed traffic environments, where human-driven and self-driving vehicles cooperate with one another in order to avoid vehicle collisions and possible deadlocks while improving traffic efficiency. In DSIP, all automated vehicles use both Vehicle-to-Vehicle (V2V) communications and traffic lights to traverse the intersection safely. On the other hand, human-driven vehicles simply follow the traffic lights just like they do today. Under the protocol, the automated vehicles synchronize when there are no human-driven vehicles around the intersection. In addition, Cooperative Perception is used to detect the presence of human-driven vehicles, where all automated and connected vehicles sense and share the presence of the human-driven vehicles at the intersection. Our simulation results show that DSIP increases the traffic throughput of the intersections compared to common signalized intersections and other V2V-based intersection protocols.
Is corruption a greater burden for registered MSEs? Evidence from Zambia

If corrupt bureaucrats target registered firms, then corruption may discourage registration. Using data from a survey of 4,801 micro and small enterprises (MSEs) in Zambia, this paper looks at whether corruption is a more or less serious problem for registered MSEs. Consistent with earlier studies, the results suggest registered MSEs are more concerned about corruption than unregistered firms are. The paper also proposes two reasons why corruption might affect registered MSEs differently than it affects unregistered firms. We first suggest that registered firms might meet with government officials more often than unregistered firms, giving corrupt officials more opportunities to demand bribes from them, but we also suggest that registered firms might be less vulnerable when officials demand bribes because they are more able to complain about bribe demands. This could offset registered firms' disadvantage because of more frequent meetings. The evidence supports the first, but not the second, hypothesis. Registered firms were more likely to meet with government officials but were not consistently less likely to pay bribes when they did meet with them.
Augmenting usual care SSRIs with cognitive behavioral therapy for insomnia to improve depression outcomes in youth: Design of a randomized controlled efficacy-effectiveness trial.

Abstract Importance Extant treatments for youth depression are only modestly effective. Alternative approaches are needed to improve health outcomes. A novel approach to improve depression outcomes is suggested by epidemiological studies finding that insomnia often predates and may contribute to depression risk. We test whether treating insomnia among youth starting a new course of SSRI antidepressants improves depression outcomes. This paper describes our study design. Design 2-arm randomized controlled efficacy-effectiveness trial. Setting A large non-profit health maintenance organization. Participants 165 adolescents aged 12–19 with research-confirmed depression and insomnia diagnoses, starting a new episode of selective serotonin reuptake inhibitor (SSRI) antidepressant treatment prescribed by their usual care provider. Interventions Two sleep interventions, each 6–7 sessions, both overlaying “treatment as usual” (TAU) SSRIs: a sleep hygiene (SH) attention control condition, and cognitive-behavioral therapy for insomnia (CBT I). Conclusions and relevance If CBT-I improved sleep is shown to improve depression-related outcomes, this may provide an additional, easily tolerated intervention for an important public health target. Trial Registration: clinicaltrials.gov , NCT02290496 , https://clinicaltrials.gov/ct2/show/NCT02290496 .
Molecular mechanisms underlying the memory-enhancing effects of estradiol

This article is part of a Special Issue "Estradiol and cognition". Since the publication of the 1998 special issue of Hormones and Behavior on estrogens and cognition, substantial progress has been made towards understanding the molecular mechanisms through which 17β-estradiol (E2) regulates hippocampal plasticity and memory. Recent research has demonstrated that rapid effects of E2 on hippocampal cell signaling, epigenetic processes, and local protein synthesis are necessary for E2 to facilitate the consolidation of object recognition and spatial memories in ovariectomized female rodents. These effects appear to be mediated by non-classical actions of the intracellular estrogen receptors ERα and ERβ, and possibly by membrane-bound ERs such as the G-protein-coupled estrogen receptor (GPER). New findings also suggest a key role of hippocampally-synthesized E2 in regulating hippocampal memory formation. The present review discusses these findings in detail and suggests avenues for future study.
The Broad Nature of Globalization: A Review of Globalization, 3rd edited by C. Gopinath (Cheltenham, UK: Edward Elgar, 2018, xii + 277 pages); and of The Handbook of Globalization 3rd ed edited by Jonathan Michie (Cheltenham UK: Edward Elgar, 2019, ix + 475 pages)

Globalization is an important multidimensional phenomenon. While there are many perspectives and definitions of globalization, it generally refers to the narrowing of national differences and cross...
A method for calculating BMI z-scores and percentiles above the 95th percentile of the CDC growth charts

The 2000 CDC growth charts are based on national data collected between 1963 and 1994 and include a set of selected percentiles between the 3rd and 97th and LMS parameters that can be used to obtai...
Vortex coronagraphs for the Habitable Exoplanet Imaging Mission concept: theoretical performance and telescope requirements

The Habitable Exoplanet Imaging Mission concept requires an optical coronagraph that provides deep starlight suppression over a broad spectral bandwidth, high throughput for point sources at small angular separation, and insensitivity to temporally varying, low-order aberrations. Vortex coronagraphs are a promising solution that performs optimally on off-axis, monolithic telescopes and may also be designed for segmented telescopes with minor losses in performance. We describe the key advantages of vortex coronagraphs on off-axis telescopes such as (1) unwanted diffraction due to aberrations is passively rejected in several low-order Zernike modes relaxing the wavefront stability requirements for imaging Earth-like planets from 100 pm rms, (2) stars with angular diameters >0.1 λ / D may be sufficiently suppressed, (3) the absolute planet throughput is >10 % , even for unfavorable telescope architectures, and (4) broadband solutions (Δλ / λ > 0.1) are readily available for both monolithic and segmented apertures. The latter make use of grayscale apodizers in an upstream pupil plane to provide suppression of diffracted light from amplitude discontinuities in the telescope pupil without inducing additional stroke on the deformable mirrors. We set wavefront stability requirements on the telescope, based on a stellar irradiance threshold set at an angular separation of 3 ± 0.5λ / D from the star, and discuss how some requirements may be relaxed by trading robustness to aberrations for planet throughput.
Consistent differences in lumbar spine alignment between low back pain subgroups and genders during clinical and functional activity sitting tests

Abstract Background Subgroups of people with low back pain display differences in their lumbar alignment during tests from a clinical examination. However, it is unknown if subgroups display the same patterns during a functional activity test and if gender influences subgroup-related differences. Objectives Test if differences in lumbar alignment between two LBP subgroups are 1) present during a functional activity test of preferred sitting and 2) independent of gender. Design Cross-sectional. Method 154 participants with chronic low back pain were classified based on the Movement System Impairment Classification System by a physical therapist. Participants performed a functional activity test of preferred sitting and clinical tests of maximum flexed and extended sitting. 3D marker co-ordinate data were collected. Sagittal plane lumbar alignment, indexed by lumbar curvature angle, was calculated. A three-way mixed effect analysis of variance was used to examine effects of test, subgroup, gender, subgroup × test, gender × test and subgroup × gender. Results/findings The lumbar rotation with extension subgroup [LCA = −8.0° (−9.5,-6.5)] displayed a more extended lumbar alignment than lumbar rotation [LCA = −5.9° (−7.4,-4.4)]. Women [LCA = −10.7° (−12.3,-9.2)] displayed a more extended lumbar alignment than men [LCA = −3.2° (−4.7,-1.7)]. There was a significant gender × test interaction (p = 0.01). The subgroup × test (p = 0.99) and subgroup × gender (p = 0.76) interactions were not significant. Conclusions LBP subgroup differences in lumbar alignment are present during preferred sitting. Gender-related differences in lumbar alignment are not driving subgroup differences. These findings highlight the need to use patient-specific clinical characteristics to guide treatment of a functional activity of preferred sitting limited due to low back pain.
An Optimal Solution to a Resource Allocation Problem under COVID-19 Financial Constraints (preprint)

Public health implications of COVID-19 resulted in widespread business closures and job losses. Disruptions in the service and transportation sectors, acute reductions in income, and an uptick in unemployment were the outcome of pandemic mitigating procedures adopted by many governments. While these measures succeeded in curving death rates, they failed to protect the economy and resulted in many parts of the world in economic covidmageddon. In this paper, we use optimization tools to study a well known problem of resource allocation in microeconomics and adapt it to the financial constraints created by COVID-19. We formulate the resource allocation problem as a finite-dimensional convex program under appropriate assumptions. Important properties of the constraints and objective function are discussed, which yield the existence and uniqueness of the optimal solution under the constraints created by COVID-19. The optimality conditions and KKT conditions are derived under a constraint qualification result. We then focus on the COVID-19 allocation problem for which a closed-form optimal solution is obtained. The corresponding exogenous growth model is discussed. The Solow model is derived using raw dynamic programming. We subsequently obtain and present the relevant economic implications for the protection of economic prosperity during pandemics such as COVID-19.
An Introduction to Evidence-Based Management of Health Care

In recent years there has been an explosion of evidence-based medicine/practice. It has been the direct result of several factors: the aging of the population, the increase in patient expectations and professional expectations, the proliferation of new information technologies, and the growth of disease management modeling. Massive amounts of clinical and administrative data have been gathered and have been managed in relational databases to generate information for improving health care processes and outcomes. That information is a systematic repertory of knowledge, used often by providers, administrators, patients, and others (see Figure 1). Used properly and consistently, such evidence-based knowledge, will give users a competitive edge in the health care marketplace.
What the Internet Age Means for Female Scholars

Is the Internet-driven transformation of legal scholarship good for the girls, or bad for the girls?Will it remove some of the handicaps that have dogged women's efforts to join the ranks of scholarly "superstars"? Or will it only increase the professional obstacles still faced by women in legal academia? In this short Essay, the author tries to predict some of the promises and perils that the Internet holds for women in the legal academy.
A Comparison of Allocation Policies in Wavelength Routing Networks

We consider wavelength routing networks with and without wavelength converters, and several wavelength allocation policies. Through numerical and simulation results we obtain upper and lower bounds on the blocking probabilities for two wavelength allocation policies that are most likely to be used in practice, namely, most-used and first-fit allocation. These bounds are the blocking probabilities obtained by the random wavelength allocation policy with either no converters or with converters at all nodes of the network. Furthermore, we demonstrate that using the most-used or first-fit policies gives an improvement on call blocking probabilities that is equivalent to employing converters at a number of nodes in a network with the random allocation policy. These results have been obtained for a wide range of loads for both single-path and general mesh topology networks. The main conclusion of our work is that the gains obtained by employing specialized and expensive hardware (namely, wavelength converters) can be realized cost-effectively by making more intelligent choices in software (namely, the wavelength allocation policy).
METAL-INSULATOR TRANSITION IN AC60: RBC60 AND KC60

At zero pressure polymerized RbC{sub 60} is an insulator, whereas polymerized KC{sub 60} is a metal with a slight low-temperature resistive upturn. We report measurements of the resistivity of RbC{sub 60} under pressure, finding a hysteretic resistive transition in RbC{sub 60} near 200 K at 5 kbar, at which point the material transforms from insulator to metal. Correcting the resistivity to constant volume, both materials are metallic below the transition with a common low-temperature resistive upturn which is suppressed under compression. {copyright} {ital 1997} {ital The American Physical Society}
New partial discharge detection method for live power cable systems

A novel partial discharge detector, the REDI (resonance-type high-frequency partial discharge) sensor, is developed for picking up the high-frequency components of partial discharge (PD) current pulses from live cable systems. This sensor was applied to initial AC breakdown tests of practical joints of XLPE (cross-linked polyethylene) insulated cables, and PD could be clearly observed in all cases (the minimum apparent charge was 5 pC with 275 kV cables). The phase characteristics of PD against the applied voltage changed just before the breakdown. >
Solenoid-operated diesel injectors for low-viscosity liquid and gaseous fuels:

AbstractAlternative fuels such as liquid dimethyl ether have low viscosity that result in fuel leakage in diesel components, while natural gas and hydrogen are too compressible for diesel pressure ...
Use of harmonic ratios to examine the effect of cueing strategies on gait stability in persons with Parkinson's disease.

Abstract Lowry KA, Carrel AJ, McIlrath JM, Smiley-Oyen AL. Use of harmonic ratios to examine the effect of cueing strategies on gait stability in persons with Parkinson's disease. Objective To determine if gait stability, as measured by harmonic ratios (HRs) derived from trunk accelerations, is improved during 3 amplitude-based cueing strategies (visual cues, lines on the floor 20% longer than preferred step length; verbal cues, experimenter saying "big step" every third; cognitive cues, participants think "big step") in people with Parkinson's disease. Design Gait analysis with a triaxial accelerometer. Setting University research laboratory. Participants A volunteer sample of persons with Parkinson's disease (N=7) (Hoehn and Yahr stages 2–3). Interventions Not applicable Main Outcome Measures Gait stability was quantified by anterior-posterior (AP), vertical, and mediolateral (ML) HRs; higher ratios indicated improved gait stability. Spatiotemporal parameters assessed were walking speed, stride length, cadence, and the coefficient of variation for stride time. Results Of the amplitude-based cues, verbal and cognitive resulted in the largest improvements in the AP HR ( P =.018) with a trend in the vertical HR as well as the largest improvements in both stride length and velocity. None of the cues positively affected stability in the ML direction. Descriptively, all participants increased speed and stride length, but only those in Hoehn and Yahr stage 2 (not Hoehn and Yahr stage 3) showed improvements in HRs. Conclusions Cueing for "big steps" is effective for improving gait stability in the AP direction with modest improvements in the vertical direction, but it is not effective in the ML direction. These data support the use of trunk acceleration measures in assessing the efficacy of common therapeutic interventions.
Clinicopathological Review of 18 Cases of Liver Allografts Lost Due to Bile Duct Necrosis

Clinical, radiographic, and pathological features of 18 patients with biliary necrosis in their explanted liver allografts were reviewed. Twelve patients were men and ages ranged from 27 to 72 years. Indications for initial liver transplant (LT) were viral hepatitis (n = 7), steatohepatitic cirrhosis (n = 3), cryptogenic cirrhosis (n = 3), secondary sclerosing cholangitis (n = 2), primary sclerosing cholangitis (n = 1), biliary atresia (n = 1), and nodular regenerative hyperplasia (n = 1). Donor age ranged from 16 to 75 years. Duct-to-duct biliary anastomoses were fashioned in 13 cases; warm and cold ischemia times were not significantly different from general LT population. Seventeen allograft biopsies after recirculation had no significant findings. Post-LT, clinical and radiographic evaluation indicated biliary strictures (n = 7), bile leak (n = 7), intrahepatic abscess (n = 1), and duodenal perforation (n = 1). Radiographic vascular studies suggested hepatic arterial thrombosis or stenosis in 11 cases. Biopsies prior to retransplantation were performed on 17 patients and showed acute rejection (n = 10), biliary outflow impairment (n = 4), normal histology (n = 2), and centrilobular necrosis (n = 1). Retransplantation was performed 14 to 334 days after initial LT. Pathological examination of explants revealed perihilar duct necrosis in all cases, with bacterial colonies (n = 10) and fungal organisms (n = 2). Arterial thrombi were seen in 10 cases, and two had prominent arteriosclerosis. Infarction and centrilobular necrosis were seen in 9 and 13 cases, respectively. Four explants showed features of biliary outflow impairment. Twelve patients were alive 6 to 18 months following retransplantation. We conclude that post-LT biliary necrosis is associated with ischemia, and such a complication is rarely evident in allograft biopsies. Biliary and vascular imaging studies are essential in evaluating patients for this complication.
A PECVD diamond device for chemical gas sensing applications

Abstract This paper presents a new diamond based microelectronic gas sensor for applications that require operation at a higher and wider temperature range and in harsh environments such as process control, exhaust emission and engine monitoring. The CO gas sensing performance and detection mechanism of the new sensor have been studied by using I – V and I – t characteristics as a function of gas concentration over a wide temperature range (50–500 °C). The gas sensitivity of the sensor is high, repeatable and reproducible. The response time is in seconds to a small concentration of CO gas. Gas detection mechanism of the new sensor is attributed to the modification of the oxygen vacancies in the SnO x layer through the reduction reaction between pre-adsorbed oxygen and CO gases.
A morphological Study of the Seeds of Puchyrrhizus erosus (L.) Urban, the Yam Bean*,†

The morphology of the seeds of Pachyrrhizus erosus (L.) Urban has been described. Some information concerning the taxonomy of the genus is also included.
Neonatal Diagnosis of Spinal Cord Transection

Cervical spinal cord injury is an uncommon clinical entity in the present day. Transection of the spinal cord was first recognized as a clinical entity in 1870, after Parrot described this insult following a breech delivery.1 In the early 20th century, there were multiple reports of spinal injury at birth, all diagnosed at autopsy. We report the earliest case to date of an infant with a cervical spinal cord transection diagnosed by magnetic resonance imaging (MRI).
Geographic and Elevational Distribution of Fringed Myotis (Myotis thysanodes) in Colorado

Abstract. Fringed myotis (Myotis thysanodes) is considered a bat species of conservation concern in Colorado and in western North America. The purpose of our research was to describe the geographic and elevational distribution of fringed myotis in Colorado and consider the potential influence of the Southern Rocky Mountains on the distribution of this species. We documented, mapped, and analyzed 729 Colorado capture and occurrence records for this species, and used 546 records in a 2-way ANOVA comparing elevational distribution among sex and reproductive classes. Mean elevation of occurrence was significantly different among reproductive classes (F = 7.03, P = 0.0010) but not between sex classes (F = 0.10, P = 0.7578). These elevation results support the hypothesis that fringed myotis tend not to occur at higher elevations in the Southern Rockies. Mapped occurrence records suggest that fringed myotis exhibits a bifurcated geographic distribution, with separate populations occurring in a band along the Col...
Interactive pattern analysis and recognition-A review and an outlook

Recently interactive facilities based on computer graphics have been used to aid in the design of complex pattern analysis and recognition systems. One major objective of such interactive systems is to provide both software and hardware facilities to allow efficient human intervention at various levels of the design process. This paper will first outline the methodologies of a number of the existing interactive systems that have been implemented to date. Several remaining important problems are discussed to indicate how the interactive approach may better contribute to the analysis and recognition of complex pictorial patterns. An interactive facility, using a PDP-9 computer system, that is designed to assist data organization for pattern analysis and recognition will be described.
Bioremediation of petroleum contaminated soil using vegetation: A microbial study

Abstract The degradation of selected petroleum hydrocarbons in the rhizosphere of alfalfa was investigated in a greenhouse experiment. Petroleum contaminated and uncontaminated soils were spiked with 100 ppm of polynuclear aromatic and aliphatic hydrocarbons. Unspiked, uncontaminated soil was used as a control. Microbial counts for soils with and without plants for each soil treatment were performed 4, 8, 16, and 24 weeks after planting. Microbial numbers were substantially greater in soil with plants when compared to soil containing no plants, indicating that plant roots enhanced microbial populations in contaminated soil. Soil treatments had no effect on microbial numbers in the presence of plants.
A Detailed Study of Void Motion in Passivated Aluminum Interconnects

Void motion can be an important part of electromigration failure in interconnects. Investigating this process is difficult due to the large variation in behavior in identical samples tested under identical conditions. To deal with the large variability, we have tested 50 samples to failure at four different accelerated test conditions. Because our automated, in-situ technique images an entire test structure, the complete history of a test line is recorded. By testing many samples under direct observation, the complex motion of electromigration voids was comprehensively studied.
An examination of orthographic and phonological processing using the task-choice procedure

The task-choice procedure provides a way for assessing whether stimuli are processed immediately upon presentation and in parallel with other cognitive operations. In this procedure, the task changes on a trial-by-trial basis and the cue informing participants about the task appears either before or simultaneously with the target, which is either degraded or clear. Of interest is whether the effect of stimulus clarity will disappear when the cue is presented simultaneously with the target, suggesting capacity-free processing, or whether the effect of stimulus clarity will remain, suggesting target processing is delayed. Besner and Care developed this procedure using nonword targets and found that phonological information was not extracted in parallel with deciphering the task cue. The current experiment examined whether phonological and orthographic information could be extracted from word and nonword stimuli in a capacity-free manner. Results indicate that in both tasks some processing does occur in a ca...
D20S16 is a complex interspersed repeated sequence: genetic and physical analysis of the locus

The genomic structure of the D20S16 locus has been evaluated using genetic and physical methods. D20S16, originally detected with the probe CRI-L1214, is a highly informative, complex restriction fragment length polymorphism consisting of two separate allelic systems. The allelic systems have the characteristics of conventional VNTR polymorphisms and are separated by recombination (theta = 0.02, Zmax = 74.82), as demonstrated in family studies. Most of these recombination events are meiotic crossovers and are maternal in origin, but two, including deletion of the locus in a cell line from a CEPH family member, occur without evidence for exchange of flanking markers. DNA sequence analysis suggests that the basis of the polymorphism is variable numbers of a 98-bp sequence tandemly repeated with 87 to 90% sequence similarity between repeats. The 98-bp repeat is a dimer of 49 bp sequence with 45 to 98% identity between the elements. In addition, nonpolymorphic genomic sequences adjacent to the polymorphic 98-bp repeat tracts are also repeated but are not polymorphic, i.e., show no individual to individual variation. Restriction enzyme mapping of cosmids containing the CRI-L1214 sequence suggests that there are multiple interspersed repeats of the CRI-L1214 sequence on chromosome 20. The results of dual-color fluorescence in situ hybridization experiments with interphase nuclei are also consistent with multiple repeats of an interspersed sequence on chromosome 20.
Quasi-classical simulation of nuclear dynamics. Phase evolution of disassembling nuclei

Abstract A recently developed quasi-classical simulation model is employed for studying the dynamics of nuclei that have been compressed to double density and heated to temperatures from 3 to 10 MeV. The evolution of a system is mapped onto the equation of state for the corresponding static system. A systematic change in the disassembly process is observed as the initial temperature is raised: at low temperatures the compressional energy is released by blowing off the outer layer of nucleons leaving a single liquid residue, whereas for high temperatures the system experiences a rapid spinodal decomposition into an expanding gas of nucleons and small clusters. The filamentary character of this process may lead to experimentally observable multifragment correlations.
Flow-cytometric DNA analysis of hematopoietic and lymphoid proliferations: a comparison of fresh, formalin-fixed and B5-fixed tissues.

Abstract Flow-cytometric DNA analysis of human tumors using paraffinembedded tissue samples is becoming an increasingly popular method of determining ploidy and proliferative rate. Particularly with hematopoietic/lymphoid proliferations, little is known about how these data compare with data from fresh suspension studies, or how B5-fixed tissues compare with those fixed in formalin. For these reasons, flow-cytometric DNA ploidy and cell cycle analysis was performed on 16 hyperplastic tonsils and 28 lymphoid/hematopoietic neoplasms using fresh (or fresh-frozen) cell suspensions (FR), B5-fixed paraffin-embedded (B5), and formalin-fixed paraffin-embedded (FO) tissue. Ploidy analysis showed all tonsil specimens to be diploid regardless of preparative method; however, for the neoplastic cases the FO and B5 preparations agreed with the FR preparations in 50% and 61% of the cases, respectively. Complete agreement between all three tissue preparation methods was present in only 36% of the neoplastic cases. Percent S or S+G2M phase fractions showed relatively poor correlation between the three preparative methods, with the best correlations found between the FR and B5 samples (S phase, r = 0.44; S+G2M, r = 0.43). In conclusion, while potentially useful data can be obtained from flow-cytometric DNA analysis of fixed, paraffin-embedded lymphoid/hematopoietic tissues, the specific limitations of such analyses must be recognized. Ploidy and proliferative phase data from fixed tissue preparations are not equivalent to information obtained from fresh suspension studies. B5-fixed tissue provides an acceptable alternative to formalin-fixed tissue for such analyses.
Circulatory studies on a case of arteriovenous aneurysm

Abstract The deleterious influence of arteriovenous fistulas upon the heart was first demonstrated by Reid 1 in a series of interesting survival experiments on animals. Following the production of large arteriovenous communications in dogs, cardiac hypertrophy and dilatation and the evidence of myocardial insufficiency developed. This investigation was prompted by Reid's clinical experience with patients with arteriovenous aneurysms. In two such cases cardiac hypertrophy and dilatation had been noted by Osler and Halsted, but no causal relationship was considered. The present knowledge of the pathological physiology associated with such fistulas is in large measure due to Reid 2 , Holman 3 , Lewis and Drury, 4 but certain of the phenomena associated with this interesting condition are still incompletely understood. The results of the study of this case added a new observation to the published data regarding arteriovenous aneurysms. In general, our findings are in accord with the excellent clinical and experimental work of Holman, but differ in several respects from the investigations of Lewis and Drury.
Topographic organization of suprachiasmatic nucleus projection neurons.

The mammalian circadian pacemaker, the hypothalamic suprachiasmatic nucleus (SCN), has two subdivisions. The core is located above the optic chiasm, receives primary and secondary visual afferents, and contains neurons producing vasoactive intestinal polypeptide and gastrin-releasing peptide. The shell largely surrounds the core, receives input from nonvisual sources and contains neurons producing arginine vasopressin and calretinin. In this study, we tested the hypothesis that SCN efferent projections are topographically organized with respect to the subdivision of origin. Injections of retrograde tracers were placed in major sites of efferent termination, described from prior studies that used anterograde tracers (Watts and Swanson, [1987] J. Comp. Neurol. 258:230-252; Watts et al. [1987] J. Comp. Neurol. 258:204-229). After retrograde tracer injections in the medial preoptic area, dorsomedial and paraventricular hypothalamic nuclei, bed nucleus of stria terminalis, paraventricular thalamic nucleus, zona incerta, and medial subparaventricular zone, retrogradely labeled SCN cells are clustered in the shell with few labeled neurons in the core. After injections centered in the lateral subparaventricular zone, peri-suprachiasmatic region, lateral septum, or ventral tuberal area, the majority of neuronal label is in the core with moderate to sparse neuronal label in the shell. Both subdivisions are labeled after injections in the paratenial thalamic nucleus. The same pattern of retrograde labeling is found with four tracers, cholera toxin-beta subunit, Fluoro-Gold, the Bartha strain of pseudorabies virus, and biotinylated dextran amine. These data extend our understanding of the significance of the division of the SCN into shell and core by demonstrating that the subdivisions differ in the pattern of projections. Together with prior observations that the subdivisions differ with respect to afferents, local connections, and neuroactive substances, the present study provides an anatomic basis for discrete control of circadian function by the SCN core and shell. In this novel view, the nature of the signal conveyed to areas receiving core or shell projections varies as a function of the subdivision from which innervation is derived.
The descriptive use of neighborhood limited classification in functional morphology: An analysis of the shoulder in primates

A series of dimensions of the shoulder girdle of primates has previously been chosen as being related to function in that anatomical region. Their examination by canonical analysis suggests that they do indeed reflect aspects of the use of the shoulder in locomotion in the different primates. Further analysis is here performed using the technique of neighborhood limited classification and this confirms the basic picture presented by the previous analysis. The new method also gives more detailed information about the grouping of the specimens; thus it endorses the reality of functional divisions that appear to exist in the data. And in addition the groupings reflect differences in the structure of the shoulder that correlate well with certain taxonomic subdivisions of the order. The method maintains contact with individual specimens throughout the analysis and is capable of placing them within groups, at the boundaries of groups, within the interfaces between groups, or as satellites to groups. The new method appears to have a part to play in the description of the relationships between biological objects that is complementary to that of canonical analysis. As the mathematical concepts upon which the two techniques are based differ totally, the risk that the results might be inherent in statistical assumptions is thus averted.
Clinical spectrum of thunderclap headache

Headaches of the thunderclap variety become severe in intensity within seconds to a minute of onset. Patients with thunderclap headache are to be evaluated in an emergent fashion as many of the underlying causes are associated with significant morbidity and mortality. Although subarachnoid hemorrhage is usually the initial consideration, a multitude of other etiologies have been identified and are discussed herein. In accordance with the increased utilization of cerebral imaging, availability of noninvasive techniques to image the cerebral vasculature and interest in identifying causes of thunderclap headaches, the list of potential causes is growing rapidly. Included in this growth are the reversible cerebral vasoconstriction syndromes, terminology recently introduced to unify several disorders all presenting with thunderclap headache and similar diagnostic findings including reversible vasoconstriction of the intracranial arteries.
Trans fat bans and the human freedom: a refutation.

David Resnik (2010) offers a balanced argument against a ban on trans fatty acids. His central premises are that the science is inconclusive; freedom of choice is limited without sufficient justifi...
A Dynamic Assessment of the Wheat Export Enhancement Program

A major goal of the Export Enhancement Program (EEP) was to expand U.S. exports. This objective was empirically tested in this study for the case of wheat. An analytical approach, reflecting the impact of the EEP on global wheat trade, was developed and incorporated within a nonspatial equilibrium model of world wheat trade. The results suggest that the EEP expanded U.S. wheat exports 20 percent in 1986/87, but only 7 percent in 1987/88. Most of the actual expansion occurred in 1987/88 and was due to other factors.
Rapid lateral diffusion of functional ACh receptors in embryonic muscle cell membrane

During synaptogenesis of the skeletal neuromuscular junction, the acetylcholine (ACh) receptors dispersed over the surface of the embryonic muscle become highly concentrated at the subsynaptic membrane1,2. The mechanism by which a nerve induces such a modulation of ACh receptor topography is unknown. Of various possibilities3, the simplest explanation is that the ACh receptors, freely diffusing in the plane of the muscle membrane, are trapped at the site of nerve contact4,5. This ‘diffusion-trap’ mechanism is plausible only if the diffusion distance covered by the ACh receptors within its lifetime on the cell surface is at least comparable with the dimension of the embryonic muscle fibre (see also discussion in ref. 1). Photo-bleaching studies had suggested that this was not the case. In the present study, an electrophysiological method was used to measure the lateral diffusion of the dispersed, functional ACh receptors in the plasma membrane of cultured Xenopus embryonic muscle cells. The results suggest that these ACh receptors undergo rapid lateral diffusion with a diffusion coefficient of 2.6 × 10−9 cm2 s−1 at 22 °C. This rapid diffusion of the dispersed ACh receptors strongly supports a passive diffusion-trap mechanism for the localization of ACh receptors at the site of nerve–muscle contact.
A case of scrotal venous malformation mimicking a failed varicocelectomy

A 21-year-old man presented to interventional radiology department with several years of left scrotal pain, which exacerbated by prolonged standing and walking. The patient had undergone a left varicocelectomy at the age of 10, after which he had a persistent scrotal mass. As he grew older, the left scrotal mass continued to increase in size, and symptoms progressively worsened. Physical examination revealed a non-tender, firm left scrotal mass which remained unchanged in size after Valsalva manoeuvres. Initial ultrasound examination revealed an extratesticular, intrascrotal mass with minimal internal flow. MRI revealed a heterogeneously enhancing, low-flow venous malformation centred in the midscrotum involving multiple tissue planes. Two sessions of percutaneous sclerotherapy failed to relieve his pain. Three months after the second sclerotherapy, the patient underwent surgical resection. At the time of his postoperative visit, his left scrotal pain had significantly improved and pain with prolonged standing and walking had resolved completely.
The Nature of Root-Promoting Substances in Lycopersicon esculentum Seedlings

Determination of the organ sites and chemical nature of root-promoting substances in Lycopersicon esculentum seedlings was made. Results of organ excision indicated that the young cotyledons were the primary site of root-promoting substances. As the cotyledon matured, its root-promoting activity decreased while that of the developing plumular leaves increased. Application of 2,3,5-triiodobenzoic acid (TIBA) at 10−3 M in lanolin to the hypocotyl below the cotyledonary node significantly prevented root formation. Bioassay, using a new tomato rooting test, of the basic, acidic and bound fractions of the cotyledon extracts after paper chromatography showed biological activities in all three fractions. Gas-liquid chromatography of selected active regions of the paper chromatogram resulted in a partial tentative identification of indolepropionic acid, 5-methylindole, 5-hydroxy-indole and 3-indoleacetonitrile. The combined evidence indicated that the root-promoting substances in tomato seedlings resemble auxin compounds.
Wage Growth Implications of Fixed-Term Employment: An Analysis by Contract Duration and Job Mobility ☆

Abstract Focusing on Spain, where fixed-term workers account for a third of the wage and salary workforce, we examine the wage growth implications of fixed-term employment of varying duration while distinguishing between wage growth occurring on-the-job versus via job mobility. Wage growth among employees with indefinite work contracts largely occurs via job mobility, whereas fixed-term workers gain via job mobility as well as on-the-job. Consequently, job stayers with fixed-term contracts a year ago narrow their wage gap with respect to similar counterparts with indefinite-term contracts. Yet, this effect is solely driven by the 10.5 percentage points higher wage growth experienced by fixed-term workers with 6-months contracts able to keep their jobs beyond their initial contract period. Given the limited number of short-term temporary workers in those circumstances, the overall wage gap between past fixed-term and indefinite-term workers is unlikely to vanish in the near future.
Impact of Change in Serum Sodium Concentration on Mortality in Patients Hospitalized With Heart Failure and Hyponatremia

Background— Hyponatremia is a common electrolyte abnormality among patients hospitalized with heart failure and it is a marker for increased short-term and long-term mortality. However, little is known about the time course of hyponatremia and whether changes in serum sodium levels affect clinical outcomes. Methods and Results— Patients (n=322) hospitalized with decompensated heart failure and serum sodium P for trend P Conclusions— Among patients hospitalized with heart failure and hyponatremia, change in serum sodium concentration over time is a strong predictor of long-term survival.
Long-term effectiveness of a statewide staff development program on cooperative learning

Abstract One-hundred-fifty-eight educators who had participated in the first state-wide cooperative learning staff development training program in South Carolina were surveyed three years later to determine the level of their use of cooperative learning and the factors influencing the effectiveness of the training. The training was conducted during the 1990–1991 academic year and the survey was given in the spring of 1993. The factors investigated were the perceived quality of training, personal commitment to using cooperative learning, technical support for using cooperative learning, psychological support for using cooperative beaming, membership in a collegial teaching team focused on using cooperative learning, and demographic characteristics of the trainees. The respondents indicated on Likert type scales their agreement and disagreement to a series of statements. The results indicate that three years following their training (a) age, gender, and ethnic membership were not related to reported level of use of cooperative learning, (b) technical support and positive view of training were only slightly related, and (c) involvement in a colleagial teaching team, personal encouragement and support for using cooperative learning (from colleagues, administrators, and students), and personal commitment to cooperative learning were important influences on the long-term level of use. A regression analysis, however, found that the only statistically significant predictor of degree of long-term implementation was membership in a colleagial teaching team.
Connective tissue growth factor expression is decreased in acute ascending aortic dissections and increased in degenerative ascending aortic aneurysms

Abstract Purpose. Both aortic aneurysms and aortic dissections exhibit abnormal extracellular matrix properties. Connective tissue growth factor (CTGF) can induce connective tissue cell proliferation and extracellular matrix synthesis. The role of CTGF in thoracic aortic disease has never been investigated. We sought to compare the expression of CTGF in degenerative ascending aortic aneurysms and ascending aortic dissection. Methods. Intraoperative samples of ascending aorta were obtained from 47 patients: 16 patients had ascending aortic aneurysms with medial degeneration, 10 had acute aortic dissection, 9 had aneurysms due to chronic dissection. Control ascending aorta was obtained from organ donors and heart transplant recipients (n = 10). Patients with Marfan syndrome were excluded from this study. CTGF mRNA expression within aortic wall was semiquantitatively determined by real-time RT-PCR using GAPDH as the internal standard. Results. There was a significant increase in CTGF mRNA in degenerative aneurysms compared to control tissue (P = 0.04). Conversely, patients with acute dissection had decreased CTGF mRNA expression compared with nondissection aneurysms (P = 0.019) and controls (P = 0.06). The increase in CTGF expression in chronic dissections compared to acute dissections approached statistical significance (P = 0.075). Conclusions. The altered tissue levels of CTGF in aneurysms and dissections suggest possibly different molecular pathology in these aortic disorders. Further investigation regarding the role of CTGF in thoracic aortic disease is warranted.
Synapse development within the spinal trigeminal nucleus

Pars interpolaris of the spinal trigeminal nucleus of kittens has been studied with the electron microscope at birth and at several subsequent ages during the first month of life. Attention has been given to ultrastructural maturational changes that occur in this neuropil, especially events in synaptogenesis. The results of this investigation include the following observations: (1) the neuropil, even at the earliest ages studied (three-hour-old kittens), is strikingly mature, necessitating a quantitative assessment in order to determine subtle developmental changes in synaptic patterns; (2) the number of axoaxonic contacts at birth are few, and their emergence is essentially a postnatal phenomenon; (3) it appears that theimmature Gray type II or symmetrical synapse possesses distinct cleft material and dense, parallel membrane specializations. Synaptic vesicle accumulation at this contact appears to occur after the membrane specializations have formed. A previous study by Kerr26 has shown a reduced potential for primary afferent reorganization within the spinal trigeminal nucleus when kittens are subjected to trigeminal rhizotomy after three days of age. Our observations on the development of axoaxonic synaptic arrangements in the neonatal period may provide an explanation for these earlier results.
A note on the optimum quantity of money

Abstract In a model where agents use money to offset uninsurable idiosyncratic income fluctuation, Bewley (1983) has shown that it may be impossible to satiate the demand for money as recommended by the literature on the optimum quantity of money (Friedman, 1969). This note shows, by means of an example, that even when it is possible to implement the traditional optimum quantity proposal, it may not be welfare-maximizing to do so on account of a negative distribution effect.
The use of students as experimental subjects in marketing research

The ability to generalize experimental observations to some larger environment is frequently a critical issue in marketing and consumer behavior research. A number of books and articles have been devoted to the problems associated with external validity but only recently have marketing scholars begun to examine the validity of employing students as subjects in marketing studies. The research reported in this paper was undertaken in an effort to investigate the validity of using students as surrogates for their parents along a number of selected cognitive dimensions. Testing the responses of both groups with MANOVA, it was discovered that student repsonses were significantly different from their parents on every dimension of interest. The findings suggest that had these particular student subjects been chosen as surrogates for their parents in a marketing research study, the external validity would have been seriously questioned.