cssi/SciSciGPT-SciSciNet huggingface dataset:
Latino suicidal adolescent psychosocial service utilization: The role of mood fluctuations and inattention.

Abstract Background Little is known about the specific factors related to whether or not Latino adolescents with suicide ideation (SI) will seek services. Utilizing Andersen's Behavior Model of Health Services Use (2008) the goal of this study is to identify the factors related to utilization of mental health services by Latino adolescents with SI to inform and improve suicide prevention efforts. Method Data from Wave 1 of the National Longitudinal Study of Adolescent Health was examined. Predispositional (gender, age), enabling/disabling (income, lack of insurance, difficulty obtaining medical care), and need (depressed mood, suicide attempt, perceived health, impulsivity, mood fluctuations, difficulties with attention, etc.) variables were examined via logistic regression as potential correlates of mental health service utilization. Results Twenty-eight percent of the Latino adolescents with suicidal ideation (SI) in our sample received mental health services. Need factors such as daily mood fluctuations within the past 12 months (OR=4.78) and frequent difficulty focusing attention within the past week (OR=4.96), but not impulsivity, were associated with an increased likelihood of receiving mental health services. No additional associations were observed. Limitations The current study is based on cross-sectional data. Therefore, statements about causality cannot be made. Conclusions These findings suggest that emotion regulation (e.g., daily mood fluctuations) and neurocognitive factors (e.g., difficulty with focusing attention) may be important factors to consider in the clinical assessment of Latino adolescents with SI.
Physicians' attitudes toward medical screening in a dental setting.

Objectives We assessed primary care physicians' attitudes toward medical screening in a dental setting. Methods A 5-point Likert scale (1 = very important/willing, 5 = very unimportant/unwilling) survey was mailed to a nationwide sample of primary care physicians in the United States. Descriptive statistics were used for all questions, and the Friedman nonparametric analysis of variance was used for multipart questions. Results Of 1,508 respondents, the majority felt it was valuable for dentists to conduct screening for cardiovascular disease (61 percent), hypertension (77 percent), diabetes mellitus (71 percent), and HIV infection (64 percent). Respondents were willing to discuss results with the dentist (76 percent), accept patient referrals (89 percent), and felt it was unimportant that the medical referral came from a dentist rather than a physician (52 percent). The most important consideration was patient willingness (mean rank 2.55), and the least important was duplication of roles (mean rank 3.52). Level of dentist's training was significantly (P < 0.05) more important than duplication of roles and reimbursement (mean ranks 2.84, 3.52, and 3.14, respectively), and significantly less important than patient willingness (mean rank 2.55). Conclusions Primary care physicians considered chairside medical screening in a dental setting to be valuable and worthwhile.
Implementing dynamic address changes in ContikiOS

To secure the Internet of Things (IoT) running on IPv6 over Low-Powered Wireless Personal Area Networks (6LoWPAN) by implementing a Moving Target IPv6 Defense (MT6D), there must first be a method developed to dynamically change IPv6 addresses over this resource constrained wireless network. We will discuss how we implemented this dynamic address change and how in doing so, we also had to change the Rime and MAC address thus implementing a moving target defense at Layers 2 and 3 of the OSI Model. We conducted our experiments in Contiki OS and utilized the Routing over Low-powered and Lossy Networks (RPL) protocol to perform the address changes between a node and its parent border router.
An Engagement-Based Student Typology and Its Relationship to College Outcomes.

Using data from the 2006 cohort of the Wabash National Study of Liberal Arts Education, we developed a student typology based on student responses to survey items on the National Survey of Student Engagement. We then examined the utility of this typology in understanding direct-assessment learning outcomes, self-reported gains, grade-point average, and persistence from the first to second year of college. Results from linear and logistic regression models indicated there were relationships between student types and the various outcomes, and that an engagement-based student typology could help deepen our understanding of the college student experience and college outcomes.
On the Importance of Being Honorable: Masculinity, Survival, and Conflict in the Backlands of Northeast Brazil, Ceará, 1840s-1890

On the night of June 24, 1874, the illiterate farmer Francisco Angelino de Souza attended a St. John's party in the house of Joao Pereira, located in the estate Barra do Felipe in the largely rural municipality of Jucas, province (now state) of Ceara in Northeast Brazil. The celebrations unfolded uneventfully, with the guests singing to the rhythms of a viola (small guitar, typical of the Northeastern backlands) and drinking the sugarcane brandy called cachaca until late in the night. However, unexpectedly, a fight erupted between Francisco Angelino and Antonio Rodrigues de Souza. According to eyewitnesses, Francisco Angelino stabbed Antonio's leg with his knife after he had “offended” Francisco Angelino's reputation. In the midst of this commotion, one of the party guests performed an in flagrante arrest, taking an indignant Francisco Angelino to jail, while he clamored at the top of his lungs that he “was not afraid of any man, or even of being jailed, because he had a bull, a horse, lands and money” to defend himself.
Critique of the determination of equilibrium cluster distributions by means of “direct simulation”

Abstract Equilibrium distributions of physical clusters of importance to the theory of nucleation have been determined by simulating equilibrium fluids and directly observing the microscopic fluctuations that correspond to cluster formation. In one method the vapor is spanned by a set of cells small enough to be occupied by, at the most, a single cluster, but at least large enough to accommodate a cluster. As a matter of practice it is necessary to focus on a single cell as a small system “grand ensemble” and to observe the frequencies of appearance of the various clusters within this cell, so that these frequencies can be translated into the equilibrium cluster distribution within the entire vapor. This focus on a single cell, as a reflection of the entire vapor, raises the issue of the accuracy of representation. There are some fundamental statistical mechanical requirements that must be satisfied before such accuracy is assured. These requirements are studied and enunciated in the present paper. It is demonstrated that the simulation is not one in which the system itself identifies the relevant cluster, but that, in fact, a cluster model must be defined . Further, it is demonstrated that although such simulations can be of considerable value, especially in arriving at estimates of the free energies of formation of clusters, they by no means diminish the value of more ponderous molecular theories that have an analytical rather than a computer experiment basis.
Oddball Science: Why Studies of Unusual Evolutionary Phenomena Are Crucial

Concerns about the US budget deficit are pushing government research funding toward utilitarian and translational research at the expense of basic science (Hand et al. 2013). Science funding decisions are increasingly at risk of becoming politicized, and reductions in basic science funding are often justified as eliminating wasteful government spending. Indeed, critics have named several government-funded basic research projects as examples of waste (e.g., Fahrenthold 2013). Recent examples include studies on duck penises, shrimp running on a treadmill, robotic squirrels, and snail sex. The criticized programs are typically studies of organisms with unusual morphologies or behaviors that have no obvious application to society. The appeal of such criticism is obvious; at first glance, studies of odd evolutionary topics seem frivolous, even wasteful, especially in tough economic times and when compared with applied science intended to cure disease, develop renewable energy, or improve agriculture. The temptation to argue that the federal government should fund only science with a foreseeable benefit is understandable, especially because guidelines of the National Science Foundation (NSF) require reporting the economic impacts of government-funded research in all fields. Some biology researchers have even suggested—misguidedly, in our opinion—that their field should address the interface between basic and applied science, with a focus on projects that address an applied challenge (Cooke 2011, Aarssen 2013). Furthermore, Aarssen (2013) argued that “university research—with no particular societal benefit in mind— has largely run its course” (p. 417). The problem with this view is that it assumes that human innovation arises in a logical fashion from planned research. History says otherwise: Innovations often arise from unlikely sources. This phenomenon was recognized last year with the establishment of the Golden Goose Awards for projects that may sound odd but that produce significant—usually unforeseen—health or economic benefits (Underwood 2012). Although seeking out projects that are likely to lead to applications may be a good strategy for securing funding, we maintain that reducing our ability to creatively examine unique biological phenomena will ultimately harm not only education and health but also the ability to innovate— a major driver of the global economy. The study of organisms typically centers on evolutionary innovations—the biological structures and phenomena that enable new functions or behaviors. These adaptations are often surprising and may seem bizarre, but they are the product of over 3 billion years of evolution and are often associated with the successful exploitation of new habitats. Studies of these seemingly oddball adaptations have jumpstarted myriad technological applications. They began, however, as basic scientific questions. Here, we highlight some examples that should be useful for anyone defending funding for basic biological research.
Multiple coupled waveguide switches using alternating Δβ phase mismatch

A design using alternating sections of dephasing to improve the transfer characteristics in multiple waveguide couplers is proposed. This is an extension of the Δβ coupler principle introduced by Kogelnik and Schmidt. The structure permits tuning with an applied voltage via the electrooptic effect. Adjustment of the electrode voltage can also compensate for fabrication imperfections in coupling lengths. The principle can be applied to both types of operation of the multiple waveguide coupler: (i) transfer of a signal between outermost guides, and (ii) transfer of a signal from the center guide symmetrically to an excitation of the two outermost guides. The three-waveguide Δβ coupler will be described in detail, and the results will be presented for arbitrary Nth order systems.
Chronic ethanol administration inhibits calmodulin-dependent Ca++ uptake in synaptosomal membranes

Chronic ethanol administration inhibits ATP-dependent Ca++ uptake in a preparation of synaptic membranes prepared from mice following 1, 4 and 7 days of ethanol exposure in a liquid diet. Addition of calmodulin (2.5 μg) to membranes from mice receiving the control diet produced a slight stimulation of ATP dependent Ca++ uptake. Membranes from ETOH treated mice exhibited reduced capacity to take up Ca++ in ATP-dependent fashion. When calmodulin was added to membranes isolated from mice receiving ETOH on Days 1, 4 and 7 ATP-dependent Ca++ uptake was significantly stimulated (p<0.01) compared to (1) ETOH treated membranes in absence of calmodulin, and (2) control membranes. Behavioral tolerance as estimated by bar holding technique was found to be 25, 65 and 91 percent complete for Days 1, 4 and 7 respectively. These studies demonstrate that continued exposure of mice to ethanol via consumption of an ethanol containing liquid diet inhibits one of the mechanisms involving the cytosolic buffering of intracellular Ca++ in nerve terminals. This biochemical effect seen in parallel with the development of tolerance to ethanol impairment of bar holding suggests that increased cytosolic Ca++ may aid in central nervous system adaptation to ethanol.
Correlates of hazardous drinking among Veterans with and without hepatitis C

Hazardous drinking is a major barrier to antiviral treatment eligibility among hepatitis C (HCV) patients. We evaluated differences in substance-related coping, drinking-related consequences, and importance and confidence in ability to change alcohol use among hazardous drinkers with and without HCV (N = 554; 93.5% male). We examined group differences between HCV+ patients (n = 43) and their negative HCV counterparts (n = 511). Results indicate a higher percentage of HCV+ patients report using substances to cope with possible symptoms of PTSD (P < .05) and depression (P < .01), and endorse more lifetime drinking-related negative consequences than HCV patients (P < .01). Furthermore, HCV+ patients place greater importance on changing alcohol use (P < .01) but report less confidence in their ability to change (P < .01). Use of brief assessment and feedback with skills-based interventions to decrease alcohol use may be well-received by HCV+ patients.
Projectile charge dependence of cross-sections for multiple electron capture and loss by 2 MeV/u Xe ions in nitrogen

A representative set of cross-sections for projectile multiple electron capture and loss in single collisions of 2 MeV/u Xe ions in nitrogen gas has been measured as a function of the incident charge. The cross-sections were used to describe the evolution of the projectile charge distribution as a function of target thickness and to predict the equilibrium charge distribution. A novel method is proposed for determining the projectile average equilibrium charge in gases from single collision cross-sections.
Trueness, precision, and detectability for sampling and analysis of organic species in airborne particulate matter

Recovery, precision, limits of detection and quantitation, blank levels, calibration linearity, and agreement with certified reference materials were determined for two classes of organic components of airborne particulate matter, polycyclic aromatic hydrocarbons and hopanes, using typical sampling and gas chromatography/mass spectrometry analysis methods. These determinations were based on initial method proficiency tests and on-going internal quality control procedures. Recoveries generally ranged from 75% to 85% for all target analytes and collocated sample precision estimates were generally better than 20% for polycyclic aromatic hydrocarbons and better than 25% for hopanes. Results indicated substantial differences in data quality between the polycyclic aromatic hydrocarbons and hopanes. Polycyclic aromatic hydrocarbons demonstrated better collocated precision, lower method detection limits, lower blank levels, and better agreement with certified reference materials than the hopanes. The most serious area of concern was the disagreement between measured and expected values in the standard reference material for hopanes. With this exception, good data quality was demonstrated for all target analytes on all other data quality indicators.
Why Analog-to-Information Converters Suffer in High-Bandwidth Sparse Signal Applications

In applications where signal frequencies are high, but information bandwidths are low, analog-to-information converters (AICs) have been proposed as a potential solution to overcome the resolution and performance limitations of high-speed analog-to-digital converters (ADCs). However, the hardware implementation of such systems has yet to be evaluated. This paper aims to fill this gap, by evaluating the impact of circuit impairments on performance limitations and energy cost of AICs. We point out that although the AIC architecture facilitates slower ADCs, the signal encoding, typically realized with a mixer-like circuit, still occurs at the Nyquist frequency of the input to avoid aliasing. We illustrate that the jitter and aperture of this mixing stage limit the achievable AIC resolution. In order to do so, we designed an end-to-end system evaluation framework for examining these limitations, as well as the relative energy-efficiency of AICs versus high-speed ADCs across the resolution, receiver gain and signal sparsity. The evaluation shows that the currently proposed AICs have no performance benefits over high-speed ADCs. However, AICs enable 2-10X in energy savings in low to moderate resolution (ENOB), low gain applications.
Impact mechanics of topologically interlocked material assemblies

Abstract The objective of the present study is to provide understanding of potential energy absorption and dissipation mechanisms and benefits of topologically interlocked material (TIM) assemblies under impact loading. The study is motivated by earlier findings that TIMs under low rate loading demonstrated attractive properties including the capability to arrest and localize cracks and to exhibit a quasi-ductile response even when the unit elements are made of brittle materials. It is hypothesized that TIMs due to their modularity would possess advantageous impact characteristics. In order to test this hypothesis, a series of computational experiments on the dynamic loading of TIMs are conducted. Results obtained in this study are presented for a planar TIM configuration based on a dense packing of tetrahedral unit elements to form an energy absorption layer. Finite element models are calibrated on samples fabricated using fused deposition modeling (FDM) additive manufacturing (AM). With employing the Lambert–Jonas formula to interpret the numerical data, it is demonstrated that TIMs can absorb more impact energy than conventional solid plates. An extended Lambert–Jonas model is defined such that accurate description of the impact response of TIMs is obtained.
Soil Carbon Sequestration for Sustaining Agricultural Production and Improving the Environment with Particular Reference to Brazil

ABSTRACT Agricultural ecosystems generally contain less soil organic carbon (SOC) pool than their potential capacity because of the low return and high rate of mineralization of biosolids, and severe losses due to accelerated erosion and leaching. Conversion of natural to agricultural ecosystems usually causes depletion of 50 to 75 percent of the antecedent SOC pool, thereby creating a potential sink capacity of as much as 35 to 40 Mg C/ha. The depletion of SOC pool leads to decline in soil quality and resilience with attendant reduction in biomass productivity, decreased capacity to degrade and filter pollutants, increased risks of soil degradation by erosion and other processes, and increase in emission of greenhouse gases (GHGs). The magnitude of depletion of SOC pool is greater for soils of the tropics than temperate regions, and for farms which are resource-based and managed with low-input than those managed with science-based and judicious off-farm inputs. The SOC sequestration, increasing SOC pool ...
Applications of Microprocessors in Accelerators

Microprocessors (pP) are finding a growing list of applications in accelerators and associated equipment. ?P's may be used as autonomous data loggers and process controllers and in distributed systems. A ?P is essentially a computer CPU. Applying ?P, centers around two distinct problems - completing the ?P into a computer and interfacing the computer to its environment. The computer can be completed with standard computer components. CAMAC was chosen to be the interface to the environment. CAMAC has several advantages at Fermilab. It is widely used, special function modules for accelerators have already been developed, and many accelerator personnel are familiar with it. Also, it is becoming more widely accepted internationally. A brief description of the CAMAC system is given.
The stability and prediction of depressive mood states in college students

Objective criteria for predicting dysphoric mood states in college students from measures of stress and cognitive and personality variables were developed and cross-validated. Contrary to Beck's diathesis-stress model of depression, although dysfunctional attitudes, together with the number and impact of life events, self-esteem problems, and level of traditional feminine personality characteristics, predicted concurrent levels of depressive symptoms, initial level of depression was the best predictor of future depression. Cross-validation of the criteria resulted in accuracy rates of 86 to 87%. Implications of these results and some secondary findings were discussed.
Mammalian DSCAMs: roles in the development of the spinal cord, cortex, and cerebellum?

Central nervous system (CNS) development involves neural patterning, neuronal and axonal migrations, and synapse formation. DSCAM, a chromosome 21 axon guidance molecule, is expressed by CNS neurons during development and throughout adult life. We now report that DSCAM and its chromosome 11 paralog DSCAML1 exhibit inverse ventral-dorsal expression patterns in the developing spinal cord and distinct, partly inverse, expression patterns in the developing cortex, beginning in the Cajal-Retzius cells. In the adult cortex, DSCAM predominates in layer 3/5 pyramidal cells and DSCAML1 predominates in layer 2 granule cells. In the cerebellum, DSCAM is stronger in the Purkinje cells and DSCAML1 in the granule cells. Finally, we find that the predicted DSCAML1 protein contains 60 additional N-terminal amino acids which may contribute to its distinct expression pattern and putative function. We propose that the DSCAMs comprise novel elements of the pathways mediating dorsal-ventral patterning and cell-fate specification in the developing CNS.
Emittance measurements of gallium liquid-metal ion sources

Abstract The emittances of momentum-analyzed 69 Ga + ion beams extracted from a needle-type liquid-metal ion source (LMIS) are found to be approximately twice as large in the dispersive plane ( x -direction) as in the orthogonal, nondispersive plane ( y -direction). This effect is principally attributable to dispersion of the beam in the x -direction by the mass analyzing magnet used in the experiments. This dispersion results from space-charge effects and other sources of intrinsic energy spread within the ion beams. In addition, the growth of emittance with beam intensity is less dramatic in the y direction, also suggesting the effect of energy dispersion. It is argued that y -direction emittance values should be considered as representative of the gallium LMIS whenever energy dispersive devices are not incorporated in the beam transport system. Brief descriptions of the experimental hardware are given and x - and y -direction emittance data are presented in this report.
Spatially selective laser cooling of carriers in semiconductor quantum wells

A successive four-step model is proposed for spatially selective laser cooling of carriers in undoped semiconductor quantum wells. The four physical steps include the following processes: (1) cold electrons with nearly zero kinetic energy are initially excited across a bandgap in a coherent and resonant way by using a weak laser field; (2) the induced cold carriers in two different bands are heated via inelastic phonon scattering to higher-energy states above their chemical potentials; (3) the resulting hot electrons and holes radiatively recombine to release photons, thus extracting more power from the quantum well than that acquired during the weak pump process; and (4) hot phonons in two surrounding hot barrier regions thermally diffuse into the central cool quantum well, thereby cooling the entire lattice with time. Based on this model, a thermal-diffusion equation for phonons including source terms from the carrier-phonon inelastic scattering and the thermal radiation received by the lattice from the surrounding environment is derived to study the evolution of the lattice temperature. At the same time, an energy-balance equation is applied to adiabatically find the spatial dependence of the carrier temperature for a given lattice temperature at each moment. There are two interesting findings in thismore » paper. First, a V-shape feature in the carrier temperature is predicted by numerical calculations, which becomes apparent only for initial lattice temperature above 150 K. Second, a thermal-drag of the carrier temperature is found as a result of the strong carrier-phonon scattering. The difference between the lattice and carrier temperatures resulting from the thermal-drag effect is larger in the barrier regions than in the well region.« less
Toy Model for Two Chiral Nonets

Motivated by the possibility that nonets of scalar mesons might be described as mixtures of ``two quark'' and ``four quark'' components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact with each other. Although the ``two quark'' and ``four quark'' chiral fields transform identically under $\mathrm{SU}(3{)}_{L}\ifmmode\times\else\texttimes\fi{}\mathrm{SU}(3{)}_{R}$ transformations, they transform differently under the $\mathrm{U}(1{)}_{A}$ transformation which essentially counts total ($\mathrm{\text{quark}}+\mathrm{\text{antiquark}}$) content of the mesons. To implement this, we formulate an effective Lagrangian which mocks up the $\mathrm{U}(1{)}_{A}$ behavior of the underlying QCD. We derive generating equations which yield Ward identity type relations based only on the assumed symmetry structure. This is applied to the mass spectrum of the low lying pseudoscalars and scalars, as well as their ``excitations.'' Assuming isotopic spin invariance, it is possible to disentangle the amount of ``two quark'' vs ``four quark'' content in the pseudoscalar $\ensuremath{\pi},K,\ensuremath{\eta}$-type states and in the scalar $\ensuremath{\kappa}$-type states. It is found that a small ``four quark'' content in the lightest pseudoscalars is consistent with a large ``four quark'' content in the lightest of the scalar $\ensuremath{\kappa}$ mesons. The present toy model also allows one to easily estimate the strength of a ``four quark'' vacuum condensate. There seems to be a rich and interesting structure.
Progress report of the committee on relations between terrestrial magnetism, terrestrial electricity, and solar activity

Measures of Solar, Magnetic, and Electric Activity.—The compilation and computation of measures of solar activity, magnetic activity, and electric activity, based on all available data, have been continued by the Department of Terrestrial Magnetism. Thanks to the cooperation of Professor Wolfer of Zurich, we are promptly supplied with his relative sun-spot numbers, which are published as soon as possible in the Journal of Terrestrial Magnetism and Atmospheric Electricity in order to make the data available to others. We have at present the final sun-spot numbers through 1918 and the provisional ones complete from 1919 to March 1923, inclusive. From these data, it appears that for the present cycle, the minimum sun-spot activity occurred in 1913, and an extraordinarily large maximum (103.9 for the mean of the year) in 1917; it is not yet possible to say whether the minimum has again been reached. The mean number for 1922 was 14.7, and the mean monthly numbers for January to March 1923 are, respectively: 5.3, 1.6, and 4.0. There has been no such high maximum as that of 1917 since 1870, when the mean number for the year was 139.1. For the first time since 1871 has the monthly mean number exceeded 150, as it did in August 1917, viz, 154.5.
Postsurgical, Chronic, Nonprogressive, Cutaneous Ulcers: A Possible Variant of Pyoderma Gangrenosum Associated with Diabetes Mellitus

Two patients developed persistent ulcers on the trunk after cutaneous surgery. Both had "chemical" diabetes mellitus. Bacteriologic and histopathologic studies of the ulcers were not revealing of cause. The characteristics of the ulcers are described, and are contrasted with typical lesions of pyoderma gangrenosum and Meleney's postoperative progressive synergistic bacterial gangrene. We believe these patients had variant lesions of pyoderma gangrenosum.
Distribution of free-living amoebae in James River, Virginia, USA.

A comprehensive survey to document the presence of free-living amoebae was conducted along 58 km of James River, near Richmond, Virginia, USA. Sites included tidal and non-tidal freshwater areas, near 40 combined sewer outflows, three municipal wastewater treatment plant release sites, and thermal discharge from a coal-fired power plant. Amoebae were present on all collection dates, spring through autumn, and at all sites (n=330). Five genera, Naegleria, Vannella, Acanthamoeba, Vahlkampfia, and Hartmannella were present in both the water column and sediment. The most common isolates from the water column were Naegleria and Vannella. Water conditions conducive to the presence of large quantities of fecal coliform bacteria were correlated with the prevalence of free-living amoebae. Some of the amoebae in this complex ecosystem can act as opportunistic pathogens, may play a role in diseases of aquatic organisms in this heavily urbanized river, and may present a risk to human health.
The Calculation of Normal Vapor Pressures from the Data of the Gas Current Method, Particularly in the Case of Iodine

The gas current method of determining the vapor pressure of slightly volatile substances is capable of a high degree of experimental precision and has often been applied. The question---whether the vapor pressure, so determined and subsequently corrected only for the Poynting effect, is accurately equal to the normal vapor pressure of the substance---has not hitherto been the subject of theoretical investigation. A method, dependent on recent developments in the thermodynamic treatment of mixtures of real gases is here developed for calculating the normal vapor pressure from the data of the gas current method. The suggested method requires data at varying total pressure for one inert gas at several temperatures and relatively accurate data at one atmosphere total pressure for two inert gases over the range of temperature. The one-atmosphere data for at least one of the inert gases must be of the precision desired on the normal vapor pressures. The method is applied to the case of the vapor pressure of solid iodine from 0 to 100\ifmmode^\circ\else\textdegree\fi{}C, for which substance data exist which are suitable, though not obtained for the most appropriate choice of experimental conditions. The new corrections (for deviations from the laws of ideal gases) are found to be important numerically in the case of the best measurements. The errors inherent in the various methods of applying the gas current method are briefly discussed. A graphic, empirical, method is found liable to a characteristic source of error.
Paleomagnetic secular variation study of lavas from the Massif central, France

Abstract The angular standard deviation of virtual geomagnetic poles determined from a paleomagnetic study of 31 Brunhes-age lava flows from France has been obtained. The value, referred to the axial dipole (geographic axis), is 15.2° with 95% confidence limits of 18.4° and 12.9°. This value is not significantly different from that obtained in similar studies of lavas from other midlatitude localities (Western United States and New Zealand).
Numerical solution of nonlinear hyperbolic conservation laws using exponential splines

Previous theoretical (McCartin 1989a) and computational (McCartin 1989b) results on exponential splines are herein applied to provide approximate solutions of high order accuracy to nonlinear hyperbolic conservation laws. The automatic selection of certain “tension” parameters associated with the exponential spline allows the sharp resolution of shocks and the suppression of any attendant oscillations. Specifically, spatial derivatives are replaced by nodal derivatives of interpolatory splines and temporal discretization is achieved via a Runge-Kutta time stepping procedure. The fourth order accuracy of this scheme in both space and time (for uniform mesh and tension) is established and a linearized stability analysis is provided. The Lax-Wendroff theorem on convergence to weak solutions (Lax and Wendroff 1960) is then extended to spline approximations in conservation form. An implicit artificial viscosity term (Anderson et al. 1984) is included via upwinding in conservation form in order to assure convergence to the physically relevant weak solution. The efficacy of this procedure is illustrated on the inviscid Burgers' equation where the accurate capture of a travelling shockwave is demonstrated.
The myths refugees live by: memory and history in the making of Bengali refugee identity

Within the popular memory of the partition of India, the division of Bengal continues to evoke themes of political rupture, social tragedy and nostalgia. The refugees, or more broadly speaking, Hindu migrants from East Bengal, are often the central agents of such narratives. This article explores how the scholarship on East Bengali refugees portrays them either as hapless and passive victims of the regime of rehabilitation, or eulogises them as heroic protagonists who successfully battle overwhelming adversity to wrest resettlement from a reluctant state. This split image of the Bengali refugee, as victim/victor, obscures the complex nature of refugee agency. Through a case-study of the foundation and development of Bijoygarh colony, an illegal settlement of refugee-squatters on the outskirts of Calcutta, this article will argue that refugee agency in post-partition West Bengal was inevitably moulded by social status and cultural capital. However, the collective memory of the establishment of squatters’ colonies systematically ignores the role of caste and class affiliations in fracturing the refugee experience. Instead, it retells the refugees’ quest for rehabilitation along the mythic trope of heroic and masculine struggle. This article reads refugee reminiscences against the grain to illuminate their erasures and silences, delineating the mythic structure common to popular and academic refugee histories and exploring its significance in constructing a specific cultural identity for Bengali refugees.
Repression of chondrogenesis through binding of notch signaling proteins HES-1 and HEY-1 to N-box domains in the COL2A1 enhancer site.

Objective—Notch signaling is implicated in repressing mesenchymal stem cell (MSC) chondrogenic differentiation. The mechanism of this repression and how this is modulated to permit chondrogenesis has not been elucidated. Methods—Notch intracellular domain (NICD) protein levels were monitored via western blot throughout chondrogenic differentiation of human in MSC pellet cultures. Overexpression of Notch signaling components and their effect on chondrogenesis was achieved by transfecting plasmids coding for NICD, hairy and enhancer of split 1 (Hes-1) and hairy and enhancer of split related-2 (HERP-2/Hey-1). Col2a1 and aggrecan expression was monitored via quantitative PCR. Chromatin immunoprecipitation (chIP) was utilized to test whether Hes-1 and Hey-1 bind putative N-box domains in intron 1 of Col2a1. Results—NICD protein levels were reduced during chondrogenesis of hMSC, which was mediated by TGFβ3. Col2a1 gene expression was repressed following overexpression of NICD (2-fold), Hes-1 (3-fold) and markedly by Hey-1 (80-fold). Hey-1 repressed aggrecan expression 10-fold, while NICD and Hes-1 had no effect. chIP studies show that endogenous Hes-1 and Hey-1 bind to two putative N-box domains adjacent to and as part of the Sox9 enhancer binding site located in intron 1 of Col2a1. The Hes-1 co-repressor protein transducin like enhancer (TLE) was displaced during chondrogenic differentiation and following TGFβ3 treatment. Conclusion—These results reveal novel mechanisms by which Notch signaling represses gene expression and further define the role of TGFβ to promote chondrogenic differentiation.
Fuzzy hexagonal automata and snowflakes

Abstract There is a common perception that snowflakes are six-sided and a common quip that “no two snowflakes are alike”. The 6-fold symmetry suggests that the growth is deterministic, while the differences suggest the growth is so sensitive to conditions that remarkable variety appears. We investigate fuzzy automata that give a great diversity of growth patterns, have sensitivity to background conditions, and which maintain the symmetry of snowflakes.
A Sex-Linked Mutation Affecting Rate of Feathering in Chickens

Abstract A chick from normal feathering parents was classified as “late” feathering at hatching (pins of flight feathers shorter than their respective coverts). But, at 6 weeks of age, it was completely devoid of back feathers. This bird, a male, was used in breeding tests with mates of known rate of feathering genotypes. The results of these tests indicate that this very slow feathering trait was due to a mutation at the K locus on the sex-chromosome. The new allele is dominant to late (K) and to early (k). The term “slow” is suggested and the symbol KS. The probable order of dominance of the alleles at this locus is KN→KS→K→k. No interaction was noted between the K and T loci.
Neural stem/progenitor cells initiate the formation of cellular networks that provide neuroprotection by growth factor-modulated antioxidant expression.

Recent studies indicate that transplanted neural stem/progenitor cells (NSPs) can interact with the environment of the central nervous system and stimulate protection and regeneration of host cells exposed to oxidative stress. Here, a set of animals grafted with NSPs and treated with 3-nitropropionic acid (3-NP) exhibited reduced behavioral symptoms and less severe damage of striatal cytoarchitecture than sham transplanted controls including better survival of neurons. Sites of tissue sparing correlated with the distribution pattern of donor cells in the host brain. To investigate the cellular and molecular bases of this phenomenon, we treated cocultures of NSPs and primary neural cell cultures with 3-NP to induce oxidative stress and to study NSP-dependent activation of antioxidant mechanisms and cell survival. Proactive presence of NSPs significantly improved cell viability by interfering with production of free radicals and increasing the expression of neuroprotective factors. This process was accompanied by elevated expression of ciliary neurotrophic factor (CNTF) and vascular endothelial growth factor (VEGF) in a network of NSPs and local astrocytes. Intriguingly, both in vitro and in vivo, enhanced growth factor secretion stimulated a robust upregulation of the antioxidant enzyme superoxide dismutase 2 (SOD2) in neurons and resulted in their improved survival. Our findings thus reveal a so far unrecognized mechanism of interaction between NSPs and surrounding cells accompanying neuroprotection: through mutual, NSP-triggered stimulation of growth factor production and activation of antioxidant mechanisms, cellular networks may shield the local environment from the arriving impact of oxidative stress. Disclosure of potential conflicts of interest is found at the end of this article.
Crystalline and hollow infrared fiber optics

Crystalline IR fibers and hollow waveguides are increasingly being used in infrared sensor and laser power delivery applications. Polycrystalline fibers, made from ductile materials such as the silver halides, offer the advantage of low loss at 10.6 micrometers , wide infrared transparency, and good flexibility. In contrast to these solid-core fibers, hollow waveguides made from metallic or dielectric materials deliver CO2 laser powers in excess of 1000 W, have no end reflection losses, and are usually quite rugged. Currently, IR fibers are finding exciting new uses in remote spectroscopy of chemical species and for the delivery of laser power for surgical applications.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Neutron-Inelastic-Scattering Measurements of Phonon Perturbations by Defects in Irradiated Copper

Neutron-scattering measurements have been made at 10 $K$ of phonons in a copper crystal neutron-irradiated at 4 $K$. The results, though clearly showing $q$-dependent defect-phonon perturbation effects, could not be explained entirely by simplified calculations for the $〈100〉$ split interstitial. A 300-K anneal removed the irradiation-induced line broadening and frequency shifts but only \ensuremath{\sim} 50% of the additional peak structure, which was completely removed only after an 800-K anneal.
A fixed-frequency, fixed-field, high-energy accelerator

Abstract The concept of a fixed-frequency, constant magnetic field accelerator capable of accelerating protons to energies in the GeV region and embodying the principle of strong-focusing is described. By designing the magnetic field so that the turns of the “equilibrium orbit” are separated axially as well as radially, as in a helix of expanding radius, it is possible to avoid most of the resonances associated with alternating-gradient systems. Since the focusing properties can be changed discontinuously at chosen points along the orbit, the residual coupling and error resonances do not present severe restrictions; they can be by-passed Longitudinal stability is also present since the system exhibits phase stability. Injection and extraction are easily achieved, and the final energy can be varied by extracting at chosen points along the orbit path.
Factors responsible for childhood mortality variation in rural Ethiopia.

This paper uses the 1981 National Rural Demographic Survey to document childhood mortality variations in rural areas of Ethiopia. Four significant findings are highlighted. (1) Health status of parents is identified as an important determinant of childhood mortality. (2) Religion region of residence and ethnicity interact in their effects on childhood mortality and the effect of ethnicity varies in different regions for the same religion; in some areas ethnicity may serve as a proxy for economic and cultural differences. (3) Childhood mortality is inversely related to literacy status of parents which may also reflect socioeconomic status. (4) The data show a clear difference in childhood mortality between the famine-prone areas and the rest. (EXCERPT)
Parathyroid function and the plasma citric acid and calcium response to nephrectomy.

THE relation of calcium and citric acid metabolism has been the subject of numerous studies, particularly since Dickens (1) demonstrated that the skeleton is rich in citric acid. However, it has remained a question as to whether or not there is a specific endocrine mechanism relating calcium and citric acid. Evidence presented previously from this laboratory in studies on adult dogs has shown that the hypercitricemia following nephrectomy is largely or entirely abolished if the thyroparathyroid apparatus is removed three weeks prior to nephrectomy (2). Further, that restoration of the serum calcium value of the thyroparathyroidectomized animal to normal by Vitamin D administration, did not restore the plasma citric acid response to nephrectomy. These observations suggest that increased concentration of citric acid in the circulation following nephrectomy depends specifically upon the function of the parathyroid gland.
Revised Magnitude-bound Relation for the Wabash Valley Seismic Zone of the Central United States

Seismic hazard assessment in the central United States, and in particular the Wabash Valley seismic zone of Indiana-Illinois, frequently relies on empirical estimates of paleoearthquake magnitudes ( M ). In large part these estimates have been made using the magnitude-bound method. Existing region-specific magnitude-bound relations rely heavily on only a few historical earthquakes in the central United States and eastern Canada that induced reported liquefaction features. Recent seismological studies have suggested smaller magnitudes than previously presumed for some of these earthquakes, however, and other studies have reinterpreted site-to-source distances to liquefaction features associated with some of these earthquakes. In this paper, we re-examine historical earthquakes ( M > ∼5) that occurred in the central and eastern United States and eastern Canada; some of these earthquakes triggered liquefaction and others did not. Based on our findings, we reinterpret the region-specific magnitude-bound relation for the Wabash Valley. Using this revised magnitude-bound relation, we present magnitude estimates for four prehistoric earthquakes that occurred in the Wabash Valley seismic zone during Holocene time.
A preliminary study of homotopic fetal cortical and spinal cotransplants in adult rats

Abstract Neocortical and spinal tissue from a given E16–E17 rat fetus were homotopically transplanted into lesion sites of adult rats which had undergone combined cortical and complete lower thoracic spinal cord lesions. Spinal cord transplants were placed either directly into the gap in host spinal cord or embedded in a collagen matrix. Animals were killed from 4 days to 8 months and tissues were processed for light microscopy. All cortical transplants survived and integrated with host brain. Many axons appeared to grow between the cortical transplant and subjacent host parenchyma. Only collagen-embedded spinal transplants survived. At 8 months, two animals underwent spinal cord transection and HRP implantation two vertebral segments rostral to the spinal cord transplantation site. Both animals revealed HRP-labeled neurons in the cortical transplants. It was concluded that 1) homotopically transplanted fetal cortical tissue can survive and may be capable of extending axons to midthoracic levels, and 2) a collagen matrix may enhance the survival of fetal tissues transplanted into a complete gap in host spinal cord.
Recombinant interferon alpha (rIFN alpha-2b) may retard progression of early primary myelofibrosis.

Recombinant interferon alpha (rIFNα-2b) may retard progression of early primary myelofibrosis
Effect of the UV Modification of α‐Crystallin on Its Ability to Suppress Nonspecific Aggregation

Recent studies have shown that structural modifications of alpha-crystallin during lens aging decrease it's effectiveness as a molecular chaperone. Some of these posttranslational modifications have been linked to UV radiation, and this study was undertaken to investigate the effect of UV irradiation on the ability of alpha-crystallin to suppress nonspecific aggregation. The effect of 3-hydroxykynurenine (3-HK) was also investigated as a model for its glucoside (3-HKG), a main lens chromophore that has been linked to photochemical changes in the human lens. Alpha- and gamma-crystallin solutions (1 mg/mL, 1:0.125 wt/wt) were photolyzed (transmission above 295 nm) for various time intervals. Thermal denaturation of gamma-crystallin with or without alpha-crystallin was carried out at 70 degrees C and increases in light scattering were measured at 360b nm. We found that (1) irradiation of gamma-crystallin increased its susceptibility to heat-induced scattering. The addition of alpha-crystallin protects it against thermal denaturation, although its ability to do so decreases the longer gamma-crystallin is irradiated and (2) irradiation of alpha-crystallin decreases its ability to suppress nonspecific aggregating and the presence of of 3-HK during irradiation decreases it further. Our results indicate that posttranslational modifications of alpha-crystallin due to UV irradiation affect the sites and mechanisms by which it interacts with gamma-crystallin. The kinetics of gamma-crystallin unfolding during thermal denaturation were also analyzed. We found that a simple two state model applies for nonirradiated gamma-crystallin. This model does not hold when gamma-crystallin is irradiated in the presence or absence of alpha-crystallin. In these cases, two step or multistep mechanisms are more likely.