cssi/SciSciGPT-SciSciNet huggingface dataset:
Determination of visual range from Landsat data

A method was developed to use Landsat multispectral scanner (MSS) data to estimate the visual range on the ground or the ground visibility. For a non-reflecting target the radiance seen at the satellite is due entirely to the scattered in-welling energy to the aperature of the detector. If the target is ideally black and there are no scatterers in the atmosphere, the observed radiance is zero. Simultaneous readings on the ground, and from a low flying aircraft at the time of Landsat passage facilitated modeling a wave-length dependent radiance versus altitude relationship. One factor in the relationship (the surface scattering coefficient, ao) relates directly to the surface visible range. Then, from a Landsat reading, the ground visibility can be estimated from that parameter from the relationship Visibility = K/ao where ao is determined from Landsat readings from the derived radiance function relating radiance to the geometric configuration angle 0 and b, a scattering decay constant. H = f(ao, b, 0)© (1984) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Corporate mergers and investment

Abstract There is concern that the recent wave of corporate mergers and acquisitions, largely financed by debt, raises interest rates and reduces investment. This paper demonstrates that the emphasis on the cost and availability of credit in discussions of this issue may be misplaced. As asset market model is presented which shows that an increase in debt-financed mergers could stimulate aggregate investment by raising the value of capital relative to replacement cost even though the loan rate rises and the supply of credit is unchanged.
Uvulopalatopharyngoplasty, Maxillomandibular Advancement, and the Velopharynx†

Objective To evaluate the presence of velopharyngeal insufficiency (VPI) symptoms and the associated changes of the velopharyngeal anatomy in patients who underwent maxillomandibular advancement (MMA) for persistent obstructive sleep apnea (OSA) after uvulopalatopharyngoplasty (UPPP). Methods Preoperative and postoperative cephalometric radiographs were analyzed to assess the anatomic changes of the velopharynx. In addition, a questionnaire survey was sent to the patients between 6 to 12 months after MMA. The questionnaires evaluated the presence and extent of VPI symptoms, including nasal regurgitation while eating or drinking as well as hypernasal speech. A 10-cm visual analog scale (VAS 0-10) was included to assess the impact of VPI symptoms on the patient's quality of life. In the patients who reported VPI symptoms, telephone interviews were conducted 1 year after the survey to evaluate the changes in VPI symptoms over time. Results Fifty-two of the 65 questionnaires were returned. Five patients (9.6%) reported nasal regurgitation of liquids when drinking hastily, with 2 patients reporting the occurrences as occasional and 3 patients reporting as rare. The impact of these symptoms on the patient's quality of life was minimal (VAS 0.6 ± 0.4). Regurgitation of food or hypernasal speech was not reported. The telephone interviews 1 year later revealed that the symptoms have completely resolved in all 5 patients. Comparison of the preoperative and postoperative cephalometric radiographs demonstrated the pharyngeal depth increase was 48% of the amount of maxillary advancement and the functional pharyngeal length increased 53% of the maxillary advancement. The functional depth of the pharynx after MMA was significantly greater in the patients with VPI symptoms (P = .01). Conclusion The results of this study suggest that patients who undergo MMA for persistent OSA after UPPP have a low risk of developing VPI. If symptoms occur postoperatively, they are mild and have minimal effect on the patient's quality of life; moreover, the symptoms usually resolve over time.
Risk of neonatal mortality in low-risk vertex and breech pregnancies in the United States: the effect of mode of delivery

265 266 NEONATAL COMPLICATIONS OF TERM PREGNANCY: RATES INCREASE IN A CONTINUOUS, NOT THRESHOLD FASHION AARON B. CAUGHEY, A. EUGENE WASHINGTON, RUSSELL K. LAROS, JR, University of California, San Francisco, Obstetrics, Gynecology and Repro. Sciences, San Francisco, CA OBJECTIVE: To determine when rates of short-term neonatal complications increase beyond 37 weeks of gestation. STUDY DESIGN: A retrospective cohort study of all term, cephalic, singleton births delivered at an academic medical center between 1976 and 2001. Data were abstracted from a research quality database and verified with chart review when in question. Primary outcomes included neonatal umbilical artery pH (uapH) and base excess (uaBE), as well as the presence of meconium, 5-minute Apgar scores, and admission to the NICU. Multivariate analyses were performed controlling for maternal ethnicity, weight, age, socioeconomic status, and obstetric history. RESULTS: We found that among the 36,241 women who delivered at 37 completed weeks and beyond, the rates of uapH <7.0, uapH < 7.10, uaBE#10, and uaBE #12, and the presence of meconium all increased throughout term gestations (chi-square, P < 0.001). These results persisted when controlling for potential confounders in multivariate models. CONCLUSION: We found that the rates of immediate neonatal morbidity increase with increasing gestational age. Accurate determination of these rates is important in determining at what gestational age the risk of continuing the pregnancy outweighs that of induction of labor.
Ultrastructural differentiation of Leydig cells in the fetal and postnatal hamster testis.

Leydig cells appear in the hamster testis between 12 and 13 days gestation. The cells are round to oval, with prominent lipid droplets, abundant smooth endoplasmic reticulum, large mitochondria with tubular cristae and well developed Golgi complexes. Cells of this type are found in pairs and groups around interstitial blood vessels during the last three days of gestation and up to the fourth day after birth, when regressive changes begin to appear. During the second postnatal week, most cells in the interstitial regions are undifferentiated, with only a few scattered partially differentiated Leydig cells remaining. The time during which fully differentiated Leydig cells are present encompasses the period of sexual differentiation of the reproductive ducts and the critical period for differentiation of sexual behavior.
Stereo observations of polar stratospheric clouds

[1] We present the first observations of polar stratospheric clouds (PSCs) within near-infrared (NIR) satellite images by using the Multi-angle Imaging SpectroRadiometer (MISR) to stereoscopically identify clouds with altitudes above the tropopause. Rather than using the operational MISR stereo product, a tailored stereo height algorithm operating upon MISR's most oblique viewing cameras is employed to identify PSC. Cloud top heights retrieved by this algorithm for scenes observed during the 2003 Antarctic Spring exhibit bias relative to the satellite-borne lidar, GLAS, of −0.60 ± 1.71 km for low (1–5 km altitude) tropospheric clouds, −0.35 ± 1.48 km for high (>5 km altitude) tropospheric clouds, and 0.77 ± 1.86 km for low (<18 km altitude) stratospheric clouds. During this period, MISR captured a Sep. 30th intensification of PSC spanning over 1 million sq. km and occurring as the apparent result of synoptic scale isentropic uplift associated with a potential vorticity anomaly tied to planetary waves, but likely also strengthened by a nearby tropospheric depression.
Human control of a two-variable decision system

Abstract In numerous contexts, man, by his decisions, influences the status or wellbeing of the system within which he operates. The quality of human control in such situations may be related to the level of complexity of the system being controlled. One dimension of “system complexity” is the number of decision variables. Another dimension is the degree of uncertainty that the environment imposes upon the system. The following study examined various characteristics of human decision performance in a system with two decision variables and two levels of uncertainty. Results indicate that the presence of uncertainty in the two-variable task does not impair decision performance to the extent that has been suggested in one-variable decision studies.
Reliability testing of flexible printed circuit-based RF MEMS capacitive switches

Abstract In this paper, reliability results of a novel type of electrostatically actuated RF MEMS capacitive switches developed by our group are discussed. The test setup used for reliability testing consists of the capacitive MEMS switch under test connected in series with a resistor. A specified actuation waveform is applied to the switch and the voltage waveform across the resistor is continuously recorded. The recorded waveform aids in identifying short, open, or stiction failure of the switch. Further, the waveform recorded can be analyzed to study the degradation, reliability, and lifetime characteristics of the switch. The proposed method has been used to study the reliability, failure, and hold-down test characteristics of flexible circuit-based RF MEMS switches. Reliability testing up to 75 million operations has been carried out for flexible circuit-based RF MEMS switches.
Multiplanar lumbopelvic control in patients with low back pain: is multiplanar assessment better than single plane assessment in discriminating between patients and healthy controls?

Objectives: Patients with low back pain (LBP) commonly have lumbopelvic control deficits. Lumbopelvic assessment during sagittal motion is incorporated into commonly used clinical examination algorithms for Treatment Based Classification. The purpose of this study was to investigate whether combined assessment of lumbopelvic control during sagittal and frontal plane motion discriminates between people with and without LBP better than single plane assessment alone.Methods: Nineteen patients with LBP and 18 healthy control participants volunteered for this study. The active straight leg raise (ASLR) and active hip abduction (AHAbd) tests were used to assess lumbopelvic control during sagittal and frontal plane motion, respectively. The tests were scored as positive or negative using published scoring criteria. Contingency tables were created for each test alone and for the combined tests (both positive/both negative) with presence/absence of LBP as the reference standard to calculate accuracy statistics of ...
An Experimental and Numerical Study on Steam Injection in Fractured Systems

Fractured reservoirs contain a large fraction of the world supply of oil. For viscous crudes, steam is the most successfull technique and field tests indicate that steam has the best potential to recover significant amounts of oil from fractured reservoirs. Unfortunately, there has been little laboratory work done on steam injection in such systems. The experimental system discussed here was designed to -understand the mechanisms involved in the transfer of fluids between the matrix rock and the fracture as a result of steam injection. Both continous and cyclic steam injection experiments were performed on a fractured laboratory system. Saturations were measured in-situ both in the fracture and the consolidated matrix by a CT scanner. The results indicated that there was no steam saturation in the matrix, and that conduction was the dominant heat transfer mechanism. Numerical simulations were used to model both continous and cyclic steam injection experiments. To model heat losses, heat loss models in the simulator had to be adjusted based on the analysis of the heat losses from the laboratory system with analytical models. After this adjustment, the results from the simulations agreed well with the experiments. When pressure cycling was applied in the simulations with no external heat losses, a considerable amount of steam saturation was observed in the matrix. While the experiments were done with water and steam, simulation runs were also performed for the laboratory system with oil present. Again, steam only flowed in the fracture. Oil recovery was found to be mainly caused by water imbibition into the matrix and heat conduction. Results of this work should be useful in modeling matrix/fracture transfer in dual porosity thermal models.
Tunnel and subsurface void detection and range to target measurement

Engineers and technicians at the Idaho National Laboratory invented, designed, built and tested a device capable of detecting and measuring the distance to an underground void, or tunnel. Preliminary tests demonstrated positive detection of, and range to, a void thru as much as 30 meters of top-soil earth. Device uses acoustic driving point impedance principles pioneered by the Lab. for well-bore physical properties logging. Data receipts recorded by the device indicates constructive-destructive interference patterns characteristic of acoustic wave reflection from a downward step-change in impedance. Prototype tests demonstrated that interference patterns in receipt waves could depict the patterns indicative of specific distances. A tool with this capability can quickly (in seconds) indicate the presence and depth/distance of a void or tunnel. Using such a device, border security and military personnel can identify threats of intrusion or weapons caches in most all soil conditions including moist and rocky.
Procedure for Processing Nuclear-Track Emulsions

Procedures have been investigated for processing exposed Eastman NTB Nuclear Track Plates which have thicknesses in the range of (a) $100\ensuremath{-}175\ensuremath{\mu}$ and (b) $200\ensuremath{-}260\ensuremath{\mu}$. Processing recommendations are given for developing essentially all tracks of ionizing particles, including electron tracks. The process consists in initiating development at low temperature and allowing it to go to completion at a higher temperature, checking development in a cold acid stop bath, and fixing (with nitrogen agitation) first at low and later at a higher temperature.
Unusual presentation of osteoblastoma in a patient with idiopathic scoliosis after posterior spinal fusion.

Abstract Background Context Few studies have described the diagnosis of osteoblastoma of the spine as a cause of scoliosis. These reports have described the tumor in conjunction with initial presentation of painful scoliosis. This case report presents a case of osteoblastoma 9 years removed from diagnosis and fusion of idiopathic scoliosis in the thoracic spine. Purpose To report the late presentation of an osteoblastoma of the thoracic spine 9 years after posterior spinal fusion for scoliosis. Study design Case report. Methods A 25-year-old man presented with thoracolumbar back pain and progressive neurological deficit 9 years after posterior spinal fusion for idiopathic scoliosis. Magnetic resonance imaging of the thoracic spine indicated the presence of a mass in the spinal canal causing cord compression. The patient underwent decompression with resection of the mass which was found to be an aggressive osteoblastoma. Results The patient enjoyed a full neurological recovery and has subsequently developed a recurrence at 13 months. Conclusions We present osteoblastoma as a possible cause of low back pain and neurological deficit postfusion that should be considered in a differential diagnosis.
Digital optical cellular image processing and its trends (Invited Paper)

This paper reviews some of the digital optical cellular image processing techniques that have been proposed or experimentally demonstrated.
Relaxation in shape-memory alloys—Part II. Thermo-mechanical model and proposed experiments

A variety of relaxation phenomena such as stabilization of martensite, rubber-like behavior, evolving hysteresis loops and stabilization of interfaces have been observed in various shape-memory alloys. These effects adversely impact technological applications. In Part I of this paper we proposed a phenomenological, but predictive, model of the mechanical behavior of these materials. We showed that this model reproduces the experimental observations. In this part, we extend this model to include the effects of temperature and the austenite-martensite transformation. Once again, the predictions from this extended model agree with experimental observations. We can therefore conclude that the basic phenomenological ideas combined with a few easily measured material parameters is sufficient to predict the behavior of these materials. Finally, we propose new experiments in order to probe longstanding issues concerning the mechanism responsible for the relaxation.
Chlorpropamide and tolbutamide inhibition of adenosine 3′5′ cyclic monophosphate phosphodiesterase☆

Abstract These sulfonylurea agents inhibit the cyclic AMP phosphodiesterase, and thereby could increase the steady state level of cyclic AMP in various tissues, depending upon the tissue concentrations achieved after oral or parental administration.
Failure of the emergency contraceptive levonorgestrel and the risk of adverse effects in pregnancy and on fetal development: an observational cohort study

Objective To determine pregnancy and neonatal outcome after the failure of levonorgestrel as an emergency contraceptive. Design A retrospective observational cohort study. Setting Telephone consultations concerning reproductive risk factors conducted by Telefono Rosso-Teratology Information Service, Catholic University of Sacred Heart, Rome, Italy. Patient(s) Women exposed to levonorgestrel (36 cases) compared with a control group (80 cases). Intervention(s) Teratological counseling. Main Outcome Measure(s) The rate of congenital anomalies, the prepartum or peripartum complications, and the pregnancy outcomes. Result(s) Twenty-five exposed newborns with length and weight identical to that of the control group were shown to be without increased risk of congenital malformation. No statistical differences were observed in terms of spontaneous or legal abortion and pregnancy and neonatal complications, and there was no ectopic pregnancy in either group. Conclusion(s) Although the sample size was small, in our experience, the failure of levonorgestrel as an emergency contraceptive was not associated with an increased risk of major congenital malformations, prepartum or peripartum complications, or an adverse pregnancy outcome.
Caregivers as Interventionists and Trainers: Teaching Mands to Children with Developmental Disabilities.

We evaluated the use of behavioral skills training (BST) to train caregivers to conduct procedures commonly associated with mand training. We trained two caregivers on the following procedures: (a) conducting preference assessments, (b) delivering preferred items contingent on appropriate behavior, (c) capturing and contriving motivating operations, (d) conducting probes to assess the child’s current mand repertoire, (e) errorless prompting procedures using echoic prompts, (f) vocal shaping, (g) collecting data, and (h) correcting errors. We also assessed whether a trained caregiver could in turn train their spouse on these procedures. We evaluated the effects of the intervention on the frequency of child spontaneous and prompted mands. The three caregivers performed near zero percent accuracy during baseline but increased to above 80 % accuracy with training, and high performance persisted during most maintenance probes. These results were replicated for the parent who received training from their spouse. In addition, spontaneous mands were occurring more frequently than prompted mands by the end of the study. The implications of caregivers implementing mand training procedures based on Skinner’s analysis of verbal behavior are discussed.
Shattuck Lecture--NIH and the bodies politic.

In 1940, President Franklin Roosevelt, a polio victim who understood well the suffering and devastation caused by chronic illness, made what was then a long drive out to Bethesda, Maryland, to dedicate the campus of the new National Institutes of Health (NIH). When he made this trek, our nation was just recovering from the worst economic depression in its history and was fighting to stay out of World War II. Nevertheless, Roosevelt's mind was on the peacetime to come, on this nation's posterity, and as he stood on the NIH campus he told his audience, “We cannot be a strong . . .
Structure-Activity Relationship Studies and Biological Characterization of Human NAD+-dependent 15-Hydroxyprostaglandin Dehydrogenase Inhibitors

The structure-activity relationship (SAR) study of two chemotypes identified as inhibitors of the human NAD(+)-dependent 15-hydroxyprostaglandin dehydrogenase (HPGD, 15-PGDH) was conducted. Top compounds from both series displayed potent inhibition (IC50 <50 nM), demonstrate excellent selectivity towards HPGD and potently induce PGE2 production in A549 lung cancer and LNCaP prostate cancer cells.
Tin valence and local environments in silicate glasses as determined from X-ray absorption spectroscopy

Abstract X-ray absorption spectroscopy (XAS) was used to characterize the tin (Sn) environments in four borosilicate glass nuclear waste formulations, two silicate float glasses, and three potassium aluminosilicate glasses. Sn K-edge XAS data of most glasses investigated indicate Sn4+O6 units with average Sn–O distances near 2.03 A. XAS data for a float glass fabricated under reducing conditions show a mixture of Sn4+O6 and Sn2+O4 sites. XAS data for three glasses indicate Sn–Sn distances ranging from 3.43 to 3.53 A, that suggest Sn4+O6 units linking with each other, while the 4.96 A Sn–Sn distance for one waste glass suggests clustering of unlinked Sn4+O6 units.
de Sitter's theory 'melts' Europa's polar cap

In photoelectric observations of a series of occultations of the Jovian satellite Europa by the Jovian satellite Io it was observed that increasingly larger fractions of the north polar region of the former were covered at mid-event with each successive occultation. One of the possible explanations of the observed phenomena involves the existence of a bright north polar cap for Europa. The reported investigation shows that a second explanation may be more plausible. This explanation is related to the possibility that at mid-event the projected minimum distance between the centers of the satellites was smaller than predicted by Sampson's theory.
Did the introduction of fixed-rate federal deposit insurance increase long-term bank risk-taking?

Abstract We investigate whether the introduction of fixed-price U.S. federal deposit insurance in 1933 increased the risk-taking of banks over the succeeding period. We examine 60 financial institutions and find that banks and trusts in general became more risky after the introduction of deposit insurance. However, a subset of well-performing banks appears to have reduced their risk. Deposit insurance also reduced the incentives of depositors to discriminate between ex ante weaker and stronger banks thus reducing depositor discipline in return for greater banking system stability.
Energy deposition by hot electrons in CO/sub 2/-laser-irradiated targets

$K\ensuremath{\alpha}$ emission has been measured from plane multilayered disk targets irradiated by nanosecond C${\mathrm{O}}_{2}$-laser pulses at peak irradiances of 7.5 \ifmmode\times\else\texttimes\fi{} ${10}^{14}$ W ${\mathrm{cm}}^{\ensuremath{-}2}$. Absolute levels of hot-electron preheat have been determined.
Local and regional flap closure in myelomeningocele repair: a 15-year review

Purpose A trend in large myelomeningocele defect repair involves soft tissue closure with muscle and fascial flap techniques to provide a durable, protective, and tension-free soft tissue covering. We propose that composite tissue closure yields superior outcomes regardless of defect size.
The Changing Nature of Pay Systems and the Need for New Midrange Theories of Pay

Abstract Previous research suggests that new pay systems (e.g., variable pay and skill based pay) are related to improved employee and organizational performance. Less certain, however, is why these new forms of pay systems work and under what conditions they are likely to work. Current compensation theory does not provide sufficient explanation because it relies upon grand theories, main effects, and commonalities across pay plans. It is argued that the articles in this special issue will advance our understanding of why the new pay systems are effective because they provide research propositions helpful for the study of midrange theories, interaction effects, and differences across types of pay systems.
Maternal Hypothermia: Implications for Obstetric Nurses

Hypothermia, a core body temperature of less than 95°F (35°C), is a common intraoperattve complication among adult patients and may occur in obstetric patients. Obstetric patients are predisposed to hypothermia because of vasodilation from pregnancy, administration of anesthetics and pharmacologic agents, and inherent blood loss with rapid fluid replacement during delivery. Morbidity associated with hypothermia occurs from complications such as hypotension, cardiac arrhythmias, increased oxygen consumption or respiratory depression, and disseminated intravascular coagulation. Interventions include preventive measures such as maintaining reasonable ambient room temperatures, avoiding infusion of cold solutions, and promptly assessing postoperative temperature, as well as corrective measures—rewarming the patient, placing the patient on dry surfaces, minimizing additional heat loss, and providing external heat sources.
Support for Business in the Federal District Courts: The Impact of State Political Environment

Despite extensive literature relating local socioeconomic and political environments to economic outputs of state legislatures and administrative agencies, there has been no comparable study of the impact of local environmental factors on economic policy outcomes of either state or federal trial courts. This article begins to fill this research lacuna by examining the combined and relative effects of state economic development policies and judicial background on federal district courts' economic policymaking. Probusiness state development policies are found to be positively related to support for business in federal district court decisions. Conclusions regarding the impact of environmental factors on district court policy outcomes are offered along with a comparison of this research with the larger and more developed body of state and local policy research.
Racial/Ethnic Differences in Patient Experiences With and Preferences for Computed Tomography Colonography and Optical Colonoscopy

Background & Aims: Racial/ethnic minorities are less likely than whites to undergo colorectal cancer (CRC) screening. Although computed tomography colonography (CTC) is a less invasive alternative to optical colonoscopy (OC), it is not known whether CTC will increase acceptance of CRC screening in minorities. Methods: Patients undergoing OC for clinically indicated reasons had CTC followed by same-day OC. After the sedation from the OC had worn off, a questionnaire was administered to assess pain, discomfort, bloating, embarrassment, anxiety, and patient satisfaction using a 10-point scale (1 = least, 10=greatest). Results: Of the 272 patients enrolled, there were 134 whites, 71 blacks, 53 Hispanics, and 14 who self-identified their race/ethnicity as other. Although the proportion of subjects who preferred CTC over OC was not significantly different (52.9% vs 47.1%, P = .36), racial/ethnic minorities were significantly less likely than whites to prefer CTC over OC (whites, 65.7%; blacks, 45.1%; Hispanics, 35.8%; and other, 35.7%; P P = .001) and were significantly less willing to undergo CTC again in the future (whites, 95.5%; blacks, 80.3%; Hispanics, 84.9%; and other, 85.7%; P = .006). Conclusions: Compared with white patients, OC is better tolerated and is preferred over CTC for evaluation of the colon among racial/ethnic minorities. Although CTC is less invasive than OC, our findings suggest that CTC is unlikely to overcome racial/ethnic disparities in CRC screening.
The interaction of RNA polymerase and DNA. Effects on the helix-coil transition and light scattering.

Abstract To characterize the interactions of RNA polymerase with DNA, we have investigated the thermal transitions of poly[d(A-T] bound to RNA polymerase from Escherichia coli and the aggregation properties of the enzyme with DNA. The melting curve of the DNA-enzyme complex demonstrates a sharply lowered melting temperature for part of the DNA, whereas for another fraction the double helix is stabilized. This indicates that the DNA-binding site of RNA polymerase serves two functions: (1) to disrupt the double helix at one point, and (2) to maintain the duplex form at other points. The aggregation of DNA and RNA polymerase has been monitored by turbidity measurements, and conditions have been delineated under which aggregation is minimized. Holoenzyme added to double-stranded DNA or single-stranded DNA has little or no tendency to aggregate under most conditions. Core enzyme, on the other hand, aggregates extensively with double-stranded DNA, and only under conditions of low salt (10 mM KCl), without Mg2+, or at high salt (300 mM KCl), with or without Mg2+, can this aggregation be eliminated. Core enzyme also does not aggregate in the presence of single-stranded DNA. These aggregation properties are interpreted as evidence for more than one DNA-binding site on RNA polymerase.
The effect of carbon on the strain-rate sensitivity of iron single crystals

The strain-rate sensitivity of iron crystals containing carbon in the range of 0.005 to 500 pm has been examined at 298° and 198°K. The strain-rate sensitivity was related to the dislocation velocity exponent using the strain-rate change technique of Johnston and Stein.(6) It was found that the dislocation velocity exponent increased with increasing carbon content at 298°K and was approximately constant at 198°K. The strain-rate sensitivity was examined on the basis of the various theories that relate strain-rate sensitivity to the dislocation obstacles responsible for the lattice friction stress in iron. It was concluded that strain-rate sensitivity of the crystals cannot be adequately explained on the basis of a single thermally activated process.
Direct and indirect coupling of primary production and diel nitrate dynamics in a subtropical spring-fed river

We used high-frequency in situ measurements of nitrate (NO { ) and dissolved oxygen (DO) from the springfed Ichetucknee River, Florida, to derive multiple independent estimates of assimilatory nitrogen (N) demand, and to evaluate the short-term dependence of heterotrophic assimilation and dissimilation (e.g., denitrification) on gross primary productivity (GPP). Autotrophic N assimilation estimates derived from diel DO variability and GPP stoichiometry agreed closely with estimates based on integration of diel variation in NO { concentration, although the correspondence of these metrics depended on the method used to estimate NO { baselines. In addition, day-to-day changes in nocturnal NO { concentration maxima were strongly negatively correlated with day-to-day changes in GPP. Diel temperature variation in the Ichetucknee River indicated that this pattern could not be explained by hydrologic dispersion, while relationships between N assimilation and O2 production at hourly intervals indicated minimal physiological lags. The estimated magnitude of heterotrophic assimilation was small, indicating that the relationship between changes in GPP and changes in nocturnal NO { maxima reflects sensitivity of denitrification to variation in exudation of labile organic matter by primary producers. We estimate that , 35% of denitrification may be fueled by the previous day’s photosynthesis; this result is consistent with the broader hypothesis that the magnitude of autochthonous production in aquatic systems influences the fate of N via both direct and indirect mechanisms.
A closed-form solution to single scattering for general phase functions and light distributions

Due to the intricate nature of the equation governing light transport in participating media, accurately and efficiently simulating radiative energy transfer remains very challenging in spite of its broad range of applications. As an alternative to traditional numerical estimation methods such as ray-marching and volume-slicing, a few analytical approaches to solving single scattering have been proposed but current techniques are limited to the assumption of isotropy, rely on simplifying approximations and/or require substantial numerical precomputation and storage. In this paper, we present the very first closed-form solution to the air-light integral in homogeneous media for general 1-D anisotropic phase functions and punctual light sources. By addressing an open problem in the overall light transport literature, this novel theoretical result enables the analytical computation of exact solutions to complex scattering phenomena while achieving semi-interactive performance on graphics hardware for several common scattering modes.
Effect of retinoids on the growth of squamous cell carcinoma of the palate in rats

The in vivo effects of retinoids on head and neck tumors were studied using Fisher 344 rats with squamous cell carcinoma implanted in the palate. Retinoids were given orally to rats, starting 2 weeks after tumor implantation. The animals were killed at 4 weeks, and the tumor volumes and body weights were measured. The animals had a greater response to all-trans-retinoic acid (58 per cent) and 13-cis-retinoic acid (60 per cent) than to all-trans-retinol (20 per cent) and 13-cis-retinal (30 per cent). Comparison of both tumor volumes and body weights among the retinoid-treated groups revealed that the body weights increased while the tumor volumes decreased. Retinoids seem to inhibit local tumor growth through their effects on host cellular and humoral immunity and through the inhibition of tumor cell keratinization.
Distribution, Morphology, and Origin of Ridges and Arches in Mare Serenitatis

Lunar mare ridges and arches in Mare Serenitatis were mapped to understand better their mode of formation. Maps of these features indicate that several pre-mare impacts in the Serenitatis area may be responsible for the localization of the circular ridge systems and that the subsurface, pre-mare topography is more complex than previously recognized. Apollo Lunar Sounder cross sections of ridge systems in southern Serenitatis indicate 50 to 100 m of local relief on these features. Small-scale features of ridges, such as medial lineations and lobate margins, do not conclusively define the origin of the ridges. However, estimates of crustal shortening from Lunar Sounder data and the coincidence of the major ridge system with the Serenitatis mascon suggest that ridges and arches were formed by gravitational readjustments of the mare fill along four probable impact structures and along a north-trending fracture pattern.
3D brain mapping using a deformable neuroanatomy

This paper presents two different mathematical methods that can be used separately or in conjunction to accommodate shape variabilities between normal human neuroanatomies. Both methods use a digitized textbook to represent the complex structure of a typical normal neuroanatomy. Probabilistic transformations on the textbook coordinate system are defined to accommodate shape differences between the textbook and images of other normal neuroanatomies. The transformations are constrained to be consistent with the physical properties of deformable elastic solids in the first method and those of viscous fluids in the second. Results presented in this paper demonstrate how a single deformable textbook can be used to accommodate normal shape variability.
Insights into the oligomeric states, conformational changes, and helicase activities of SV40 large tumor antigen.

Abstract The large T (LT) antigen encoded by SV40 virus is a multi-domain, multi-functional protein that can not only transform cells but can also function as an efficient molecular machine to unwind duplex DNA for DNA replication. Here we report our findings on the oligomeric forms, domain interactions, and ATPase and helicase activities of various LT constructs. For the LT constructs that hexamerize, only two oligomeric forms, hexameric and monomeric, were detected in the absence of ATP/ADP. However, the presence of ATP/ADP stabilizes LT in the hexameric form. The LT constructs lacking the N- and C-terminal domains, but still retaining hexamerization ability, have ATPase as well as helicase activities at a level comparable to the full-length LT, suggesting the importance of hexamerization for these activities. The domain structures and the possible interactions between different LT fragments were probed with limited protease (trypsin) digestion. Such protease digestion generated a distinct pattern in the presence and absence of ATP/ADP and Mg2+. The most C-terminal fragment (residues 628-708, containing the host-range domain), which was thought to be completely unstructured, was somewhat trypsin-resistant despite the presence of multiple Arg and Lys, possibly due to a rather structured C terminus. Furthermore, the N- and C-terminal fragments cleaved by trypsin were associated with other parts of the molecule, suggesting the interdomain interactions for the fragments at both ends.
The influence of efferent, proprioceptive, and timing factors on the accuracy of eye-hand tracking

Oculomotor tracking of one's moving hand is considerably more accurate than tracking of an external target undergoing comparable motion. To identify the factors contributing to this enhancement of tracking accuracy, the influence of visual, proprioceptive, and efferent cues on tracking performance was assessed. Related observations were made on the influence both of linear and topological transformations between target and hand position on tracking accuracy. The experimental findings indicate that if a target light is attached to one's hand, a) the target can be tracked with comparable accuracy for active and passive limb movements, and b) when the entire hand rather than just the target light is visible, pursuit velocity is higher and more closely matches target velocity. If a linear transformation is introduced between hand and target positions, nearly identical tracking accuracy is found with voluntary and involuntary limb movements. By contrast, topological transformations degrade target tracking accuracy for passive but not for voluntary limb movements. The implications of this finding are discussed.
Hidden skills that support phased and agile requirements engineering

Phased development does requirements engineering in one or a small number of extended phases occurring early in a project. Agile development also does requirements engineering, but in thousands of small conversations spread throughout the development life cycle. Each depends on subtly different skills and expertise to perform its practices --- agile development depending heavily on ability to change working code, phased development depending heavily on foresight. This paper surveys the special skills that each style of requirements engineering depends on in order to promise and deliver.
Study on the Tribological Property of Bionic Lead Rail Using ABAQUS

Archard wear theory, which describled the relationship between wear volume and material hardness, coasting distance and loading, was the classical theory of tribology problem. According to Archard wear theory, bionic lead rail was compared with ordinary lead rail based on ABAQUS software in the same conditions. Friction and wear property of bionic lead rail were studied, including the maximum contact surface, the distribution of working point of friction force and transformation law of friction force. The results indicated that the maximum contact surface of bionic friction pair decreased obviously and the variation of contact surface was steady. The distribution of working point of friction force for ordinary lead rail was relatively concentration. The distribution of working point of friction force for bionic lead rail was relatively dispersion. Friction force for bionic friction pair decresed to some extent, but the peak friction force was relatively larger.
Incidence of Surgical Site Infection After Spine Surgery: What Is the Impact of the Definition of Infection?

Background Orthopaedic surgical site infections (SSIs) can delay recovery, add impairments, and decrease quality of life, particularly in patients undergoing spine surgery, in whom SSIs may also be more common. Efforts to prevent and treat SSIs of the spine rely on the identification and registration of these adverse events in large databases. The effective use of these databases to answer clinical questions depends on how the conditions in question, such as infection, are defined in the databases queried, but the degree to which different definitions of infection might cause different risk factors to be identified by those databases has not been evaluated.
RADIOACTIVE EUROPIUM 150 AND GADOLINIUM 150

The enriched isotopes of samarium were bombarded with 6.7-Mev protons. A well-defined 13.7-hour activity was measurable in all of the enrichments. Comparison of relative initial saturation intensities clearly indicated that the activity should be assigned to ${\mathrm{Eu}}^{150}$. The activity is the result of negatron emission. The negatron spectrum has maximum energy of 1.07 Mev, and is classified as a first-forbidden transition on the basis of the $log(\mathrm{ft})$ value.
Involvement of dopamine D1 and D2 receptors in the regulation of proenkephalin mRNA abundance in the striatum and accumbens of the rat brain.

: The effects of short-term treatment (6 h) with selective D1 or D2 agonists and antagonists on the mRNA for proenkephalin in the medial and anterior aspects of the cau-date-putamen and the nucleus accumbens were assessed by in situ hybridization histochemistry. Proenkephalin mRNA abundance was significantly changed in the striatum and accumbens in response to D2 receptor manipulation. D2 blockade with haloperidol or raclopride increased, whereas D2 stimulation with LY-171555 (D2 agonist) decreased, striatal and accumbens proenkephalin mRNA abundance. Antagonism of D1, receptor activity with SCH-23390 significantly decreased proenkephalin mRNA abundance in all brain regions. Concurrent administration of the D1, agonist SKF-38393 prevented the SCH-23390 effect in all brain areas. The data demonstrate that acute treatment with dopaminergic D2 agonists and antagonists affects proenkephalin mRNA abundance in the striatum and accumbens via a D2 receptor mechanism, consistent with the concept that D2 receptor function inhibits the synthesis of the mRNA encoding the enkephalin peptides. Moreover, Df receptor activity, directly or indirectly, exerts modulatory effects on proenkephalin mRNA abundance in the striatum and nucleus accumbens.
Stroke in a young adult with familial plasminogen disorder.

We report a new plasminogen disorder detected in a 29-year-old man with a cerebellar infarct. To our knowledge, plasminogen disorders have not been previously linked with stroke.Tests for well-recognized causes of stroke were negative. However, a screening hypercoagulation profile indicated low functional levels of plasminogen activity. Immunologic plasminogen (Laurell technique) was 64% of normal (normal level, 80-130%). The rate of plasmin generation induced by adding urokinase to plasma was also low. Plasminogen activator, free protease, and alpha 2-plasmin inhibitor levels were normal. Family studies detected a similar plasminogen abnormality in the patient's mother and 9-year-old son, both of whom are asymptomatic.Our patient shows a congenital, heterozygous, functionally abnormal plasminogen. Although the exact relationship to stroke is unclear, we suggest screening young patients with unexplained stroke for plasminogen defects using commercially available assay systems.
Picosecond Time-Resolved Fourier Transform Raman Spectroscopy of 9,10-Diphenylanthracene in the Excited Singlet State

Time-resolved Fourier transform Raman spectroscopy of the highly fluorescent chromophore 9,10-diphenylanthracene (DPA) in cyclohexane and ethanol is described. Raman spectra of the first excited singlet state of DPA were obtained with 100-ps resolution at several time delays between pump pulses at 355 nm and probe pulses at 1064 nm. The near-infrared excited-state Raman scattering is enhanced by resonance with an excited-state transition of DPA. The excited-state Raman bands decay in about 5-6 ns. Evidence for interaction of the solvent with the DPA excited state is observed in the cyclohexane C-H stretching bands.
Effects of type I interferon-inducing agents on hepatic metallothionein.

Two inbred strains of mice were used in this study, the C57BL/6J which is reported to be a high interferon producer and the C3H/HeJ which is reported to be a low interferon producer. Each mouse received a single i.p. injection of either Newcastle disease virus (NDV) or the double-stranded nucleotide, polyinosinic acid-polycytidilic acid (poly (rI.rC)), both type I interferon inducers, or cadmium chloride, a known inducer of metallothionein (MT), and were killed 24-hr later. Treatment of the C57BL and C3H mice with 1 mg Cd/kg caused a 14- and 16-fold increase in hepatic MT concentrations, respectively. In both strains, this induction was accompanied by an increase in the hepatic concentration of zinc but not copper. There were no observed changes in the circulating levels of interferon. In the C57BL mice, both the administration of poly (rI.rC), at a dose of 10 mg/kg, and NDV, at a dose of 512 hemagglutinating units/mouse, produced a 4-fold increase in the hepatic concentration of MT. Although both treatments caused an increase in levels of interferon, the increase seen with NDV was greater than that seen with poly (rI.rC). In the C3H mice, the results were quite different. Although both treatments induced hepatic MT concentrations 4- to 5-fold, the increase in interferon levels observed following the administration of poly (rI.rC) was higher than that seen with NDV and some 50-fold higher than the increase produced by the polynucleotide in the C57BL mice. The results of this study indicate that two interferon-inducing agents, poly (rI.rC) and NDV, are also capable of inducing hepatic metallothionein.
Relative toxicity of gossypol enantiomers in broilers

Use of cottonseed meal in poultry diets has been avoided in large part because of fear of gossypol toxicity. Gossypol exists naturally as a mixture of 2 enantiomers that exhibit different biological activities. Two experiments were conducted to determine the relative toxicity of gossypol enantiomers on broilers. In the first experiment, 3-d-old broilers were fed a standard diet containing 0, 100, 200, 300, or 400 mg of gossypol from gossypol acetic acid per kilogram of diet from 3 to 42 d of age. This form of gossypol contains both enantiomers in an equimolar ratio. Each dietary treatment consisted of 6 replicate pens of 4 birds. In the second experiment, 3-d-old broilers were divided into 15 pens of 4 birds each and fed a standard diet supplemented with either no gossypol or one of the gossypol enantiomers at 200 or 400 mg/kg of diet from 3 to 21 d of age. In both experiments, feed intake and BW gain were measured. In addition, several organ and tissue samples were collected at 21 d (experiments 1 and 2) and 42 d (experiment 1) of age and analyzed for gossypol. In experiment 1, feed consumption and BW gain were reduced (P < 0.05) at 21 and 42 d for the birds fed the highest level of gossypol. The concentration of gossypol in the heart, kidney, and plasma were equivalent at 21 and 42 d of age. In experiment 2, total feed consumption was reduced only in birds consuming (-)-gossypol, but BW gains were lower for birds fed either enantiomer. However, (-)-gossypol was more detrimental to growth than (+)-gossypol. The liver had the highest tissue concentration of both enantiomers, and accumulation of (+)-gossypol was higher than (-)-gossypol in all tissues examined. No racemization of the enantiomers was apparent in the tissues analyzed. Our results indicated that both gossypol enantiomers were toxic to broilers but that (-)-gossypol was more harmful to efficient broiler production than (+)-gossypol.