cssi/SciSciGPT-SciSciNet huggingface dataset:
Photochemical concentration modulation and its application to the detection of low concentration photochemical pollutants in the air

Abstract Conventional spectroscopic methods of detection of low concentration pollutants in the air generally suffer from severe optical noise as well as electronic noise. This optical noise usually includes characteristic overlapping noise, background radiation noise and d.c. beam fluctuation noise and in many cases is difficult to eliminate using conventional methods. However, because most photosensitive pollutants will decompose into other chemical species under UV illumination at a specific wavelength, we can vary the concentrations of these pollutants by controlling the intensity of the UV beam while keeping the optical noise unchanged. Thus, by using this intensity-controlled UV beam, we can create a controlled different between the signal and the noise. Several techniques can then be used to detect this modulated signal in the presence of the unmodulated noise. We shall report two approaches for measuring the concentrations of pollutants following this concept of concentration modulation. One entails shifting monitored line position to a high absorption, low noise region of the spectrum by observing the products produced by concentration modulation. The other uses modern communication engineering technology to extract the weak modulated signal from the noise. Experimental results of the first approach using NO 2 as an example are reported in detail. The results verify both qualitatively and quantitatively the basic concept of concentration modulation and show an improvement in sensitivity such that 0.5 ppm NO 2 is measurable using this method. The sensitivity may be difficult to reach with conventional spectroscopic methods using the same path length.
Modulation of the hypoxic sensory response of the carotid body by 5-hydroxytryptamine: role of the 5-HT2 receptor

Previous studies have shown that glomus cells of the carotid body express 5-hydroxytryptamine (5-HT). The aim of this study was to elucidate the role of 5-HT on the hypoxic sensory response (HSR) of the carotid body. Sensory activity was recorded from multi-fiber (n=16) and single-fiber (n=8) preparations of ex vivo carotid bodies harvested from anesthetized, adult rats. 5-HT (3 microM) had no significant effect on the magnitude or on the onset of the HSR. However, 5-HT consistently prolonged the time necessary for the sensory activity to return to baseline following the termination of the hypoxic challenge. Ketanserin (40 microM), a 5-HT2 receptor antagonist completely prevented 5-HT-induced prolongation of the HSR, whereas had no effect on the control HSR (onset, magnitude, and time for decay without 5-HT). Carotid bodies expressed 5-HT, but hypoxia did not facilitate 5-HT release. These observations suggest that 5-HT is not critical for the HSR of the rat carotid body, but it modulates the dynamics of the HSR via its action on 5-HT2 receptors.
Lower-extremity amputations in patients with diabetes: pre- and post-surgical decisions related to successful rehabilitation

Background Peripheral vascular disease and diabetes account for the majority of lower-extremity amputations in the adult population. Whenever a patient presents to a surgeon regarding a diseased limb, the initial basic decision is to determine whether to attempt limb salvage or proceed with an amputation. Unfortunately, limb salvage is not an option for many of these patients. Once amputation is chosen as a treatment option, the optimal level of amputation has to be determined by the surgeon, who is then faced with selecting the optimal level of amputation compatible with wound healing and subsequent prosthetic fitting. Methods Methods for objectively determining optimal amputation level include vascular evaluations, assessing the level of cellulites or osteomyelitis, or intra-operatively, by looking at the amount of bleeding in skin flaps. Results The net outcome is that there is currently no universally accepted method for determining the level of amputation for successful wound healing or for preventing subsequent higher amputations. Conclusions What is generally recognized is that there are disparities in the rates of amputation for type 1 versus type 2 diabetic patients, for different ethnic groups and for patients with multiple co-morbidities. However, with advances in surgical techniques and with modern prosthetics, all categories of patients are benefiting from surgeries in which a longer residual limb can be kept (within surgical constraints related to proper wound healing), and where appropriate biomechanical considerations are taken into account.
Operational control of multi-load vehicles in an automated guided vehicle system

Abstract An alternative to increasing the AGV fleet size in order to improve the availability of vehicles is to introduce vehicles with multiple load carrying capacity. This paper attempts to study the effect of different dispatching rules in the case of multi-load vehicles, on the overall performance of an AGVS. A comparison between the performance of a fleet comprising unit load vehicles is also made with that of multi-load vehicles.
Induction of corneal myofibroblasts by lens-derived transforming growth factor β1 (TGFβ1): A transgenic mouse model

Abstract Purpose Transforming growth factor β (TGFβ) is an important cytokine in corneal development and wound healing. Transgenic mice that express an active form of human TGFβ1 driven by a lens-specific promoter were used in the current study to determine the biological effects of lens-derived TGFβ1 on postnatal corneal development and homeostasis. Methods The postnatal corneal changes in the TGFβ1 transgenic mice were examined by fluorescein labeling and histology. Epithelial/endothelial-to-mesenchymal transition (E/EnMT) in the transgenic mouse cornea was demonstrated by immunostaining for α-smooth muscle actin (α-SMA) and cadherin-11. Expression of E- and N-cadherin in the corneal epithelial and endothelial cells, respectively, was analyzed by in situ hybridization. Results Among the established TGFβ1 transgenic lines, mice from line OVE853 and OVE917 had normal-sized eyeballs but developed a corneal haze after eyelid opening. Histological examination showed that prenatal corneal development appeared to be normal. However, after postnatal day 7 (P7), the corneal endothelial cells in transgenic line OVE853 began to lose normal cell–cell contact and basement membrane structure. The endothelial layer was eventually absent in the inner surface of the transgenic mouse cornea. The morphological changes in the cornea correlated with abnormal expression of α-SMA, a molecular marker of EMT, and stress fiber formation in myofibroblast-like cells, which initially appeared in the corneal endothelial layer and subsequently in the corneal epithelial and stromal layers. The E/EnMT in the transgenic mouse cornea was further demonstrated by loss of E- and N-cadherin expression in the corneal epithelial and endothelial cells, respectively, and meanwhile increasing expression of cadherin-11 in both corneal epithelium and stroma. Conclusions Elevated levels of active TGFβ1 in the anterior chamber can lead to myofibroblast formation in the corneal endothelial layer and subsequently in the corneal epithelial and stromal layers. Our data suggest that the levels of biologically active TGFβ in the aqueous humor must be under tight control to maintain corneal homeostasis. TGFβ1 is the major cytokine during wound healing. Therefore, our findings also suggest a potential mechanism to explain the loss of corneal endothelial barrier and corneal opacification after intraocular surgery or trauma.
A numerical investigation of thermal convection in a heat-generating fluid layer

Finite difference solutions of the equations governing thermal convection driven by uniform volumetric energy sources are presented for two-dimensional flows in a rectangular domain. The boundary conditions are a rigid (i.e, zero slip), zero heat-flux lower surface, rigid adiabatic sides, and either a rigid or free (i.e., zero shear) isothermal upper surface. Computations are carried out for Prandtl numbers from 0.05 to 20 and Rayleigh numbers from 5 x 10 to the 4th to 5 x 10 to the 8th. Nusselt numbers and average temperature profiles within the layer are in good agreement with experimental data for rigid-rigid boundaries. For rigid-free boundaries, Nusselt numbers are larger than in the former case. The structure of the flow and temperature fields in both cases is dominated by rolls, except at larger Rayleigh numbers where large-scale eddy transport occurs. Generally, low velocity upflows over broad regions of the layer are balanced by higher velocity downflows when the flow exhibits a cellular structure. The hydrodynamic constraint at the upper surface and the Prandtl number are found to influence only the detailed nature of flow and temperature fields. No truly steady velocity and temperature fields are found despite the fact that average Nusselt numbers reach steady values.
Fissure Removal and Needle Scraping for Evaluation of the Bacteria in Occlusal Fissures of Human Teeth

The bacterial counts obtained with a needle-scrape method for collecting plaque samples from human occlusal fissures with incipient caries were compared with the microflora remaining in the fissures as determined with a fissure removal method. Scraping of six fissures with a sterile needle recovered only 18.2% of the total recovered fissure flora. The needle-scrape method failed to detect specific cariogenic bacteria which were present in four of the fissures. Treatment of nine fissures with an antibacterial solution demonstrated that the needle method failed to detect viable bacteria in eight of the fissures which were subsequently shown to contain bacteria by fissure removal. The commonly used needle-scraping method does not appear adequate for studies on the effect of antimicrobial agents on fissure plaque.
Penetrating Keratoplasty, Deep Lamellar Endothelial Keratoplasty, and Posterior Lamellar Keratoplasty in the Horse

Corneal transplantation is a viable and successful surgical technique in the horse. Full thickness penetrating keratoplasty (PK) may be performed for melting ulcers, iris prolapse/descemetoceles, and full thickness stromal abscesses (SA). Deep lamellar endothelial keratoplasty (DLEK) and posterior lamellar keratoplasty (PLK) are split thickness penetrating keratoplasties utilized for deep stromal abscesses (DSA) with clear overlying anterior stroma. Frozen donor grafts can be used successfully for transplants in the horse eye. Corneal transplants in horses are associated with high success rates, good visual outcomes (>80%), and shorter treatment times than medical treatment alone of these eye problems alone, but the corneal transplants in horses do vascularize, have some degree of opacity, and thus exhibit some degree of graft rejection.
The vibrational spectrum of the secondary electron acceptor, A1, in photosystem I.

Photosystem I (PSI) is a multisubunit protein complex which carries out light-induced, transmembrane charge separation in oxygenic photosynthesis. In PSI, the electron-transfer pathway consists of chlorophyll and phylloquinone molecules, as well as iron-sulfur clusters. There are two phylloquinone molecules, which are located in structurally symmetric positions in the reaction center. It has been proposed that both phylloquinone molecules are active as the A 1 secondary electron acceptor in bidirectional electron-transfer reactions. The PSI A 1 acceptors are of interest because they have the lowest reduction potential of any quinone found in nature. In this work using light-induced FT-IR spectroscopy, isotope-edited spectra are presented, which attribute vibrational bands to the carbonyl stretching vibrations of A 1 and A 1 - and the quinoid ring stretching vibration of A 1 . Bands are assigned by comparison with hybrid Hartee-Fock density functional calculations, which predict vibrational frequencies, amplitudes, and isotope shifts for the phylloquinone singlet and radical anion states. The results are consistent with an environmental interaction increasing the frequency of the singlet CO vibration and decreasing the frequency of the anion radical CO vibration, relative to model compounds. This environmental interaction may be the asymmetric hydrogen bond to A 1 /A 1 - , electrostatic interactions with charged amino acid side chains, or a pi-pi interaction with the indole ring of a nearby tryptophan. Such differential effects on the structure of A 1 and A 1 - may be associated with a destabilization of the anion radical. These studies give novel information concerning the effect of the protein matrix on the PSI electron-transfer cofactor.
Capital Markets Union: The Key to Restoring the Economic Growth and the Real Convergence in the Eurozone

In the next decade or so the EU will face complete set of challenges. To confront successfully these challenges, the restoration of growth is the imperative. That means to restore the competitiveness especially on the Mediterranean littoral and hopefully the real convergence. Renewal of the North to South capital flows is the sine qua non of this development. The main tool in this endeavor is the emerging capital markets union, which will facilitate the increased activities of the venture capital – the main tool to create the new economy of innovation and creativity. But to be successful the capital markets union has to be complemented by reforms of labor markets, business creation environment and taxation. New approaches like special “economic innovation and growth” zones may be necessary. To fully implement the necessary structural reforms the cooperation of the private and public sector on both the EU and national levels is necessary.
Medical students' personal knowledge, searching proficiency, and database use in problem solving

The relationship between personal knowledge in a domain and searching proficiency in that domain, and the relationship between searching proficiency and database-assisted problem-solving performance were the foci of this study. On four assessment occasions over a 2-year period, 36 medical students solved problems in three biomedical domains (bacteriology, pharmacology, and toxicology) with and without assistance from a factual database in the relevant domain. There was little evidence of any relationship between personal domain knowledge and searching proficiency (i.e., search results, selection of search terms, improvement in selection of search terms over the course of the search, and efficiency). Search results, selection of search terms, and efficiency were found to be related to database-assisted problem-solving performance. © 1995 John Wiley & Sons, Inc.
Efficient Generation of High-Quality Unstructured Surface and Volume Grids

Procedures are presented for efficient generation of high-quality unstructured surface and volume grids. The overall procedure is based on the well proven Advancing Front/Local-Reconnection (AFLR) method. The AFLR triangular/tetrahedral grid generation procedure is a combination of automatic point creation, advancing type ideal point placement, and connectivity optimization schemes. A valid grid is maintained throughout the grid generation process. This provides a framework for implementing efficient local search operations using a simple data structure. It also provides a means for smoothly distributing the desired point spacing in the field using a point distribution function. This function is propagated through the field by interpolation from the boundary point spacing or by specified growth normal to the boundaries. Points are generated using either advancing- front type point placement for isotropic elements, advancing-point type point placement for isotropic right angle elements, or advancing-normal type point placement for high-aspect-ratio elements. The connectivity for new points is initially obtained by direct subdivision of the elements that contain them. Local-reconnection with a min-max type (minimize the maximum angle) type criterion is then used to optimize the connectivity. The overall procedure is applied repetitively until a complete field grid is obtained. An advancing-normal procedure is coupled with AFLR for anisotropic tetrahedral and pentahedral element grids. Advancing along prescribed normals from solid boundaries generates layers of anisotropic elements. The points are generated such that either pentahedral or tetrahedral elements with an implied connectivity can be directly recovered. The AFLR surface grid procedure uses an approximate physical space grid to define the surface during grid generation. The mapped space coordinates are mapped back to the actual surface at completion. Multiple surface definition patches are grouped into a single surface. A global mapping transformation is generated for the single surface using the grouped surface connectivity. The mapping coordinates are obtained by solving a coupled set of Laplacian equations. The overall procedure has been applied to a wide variety of configurations. Selected results are presented which demonstrate that high-quality unstructured grids can be efficiently and consistently generated for complex configurations.
Darkly Pigmented Lesions in Dark-Skinned Patients

It is well known that fair-haired, fair-complected individuals have an increased risk of skin malignancies. Current literature, however, gives no aid in evaluating darkly pigmented lesions in the dark-skinned patient. Blacks have an incidence of malignant melanoma from 5 to 18 times less than whites, while Hispanics have a higher incidence than blacks, but 3.5 to 4.5 times less than whites. Basal-cell epitheliomas are more likely to be darkly pigmented in both groups, leading to erroneous diagnosis and treatment as melanomas.
The Questions We Left Behind: Reflections from a Teaching Theologian

: While the ordination of women made great strides in ending gender injustice for women in church-related vocations, women also have raised other questions, specifically: the appropriate role of experience in theological discourse and moral deliberation; the displacement of advocacy by representation; and the tension between the personal and the political. Fore-mothers leave behind these issues for their after-daughters, as they meet challenges their fore-mothers in the faith could hardly imagine.
A VOLTAGE‐BASED AUTOMATIC CONTINGENCY SELECTION ALGORITHM VIA A LINEARIZATION METHOD

This paper describes a fast method for determining voltage changes due to line outages. Its extension to the identification of system islands as well as a formulation of a voltage‐based contingency selection algorithm is explained. The performance of the method is evaluated using the 6‐bus Saskatchenan Power Corporation, IEEE 14‐bus and 23‐bus Nigerian Power Systems networks neglecting the effect of voltage controls.
Incidence of sacral fractures and in-hospital postoperative complications in the United States: an analysis of 2002-2011 data.

STUDY DESIGN Retrospective study of an administrative database. OBJECTIVE To estimate the incidence of sacral fractures in the United States and report short-term outcomes after their surgical management. SUMMARY OF BACKGROUND DATA The incidence of sacral fractures in the United States is currently unknown, and these lesions have been associated with significant morbidity after their surgical management. METHODS This study used the Nationwide Inpatient Sample database for the years 2002-2011. All patients with a primary discharge diagnosis of a sacral fracture with and without a neurological injury were identified using International Classification of Diseases, Ninth Revision, Clinical Modification codes. Patients with a diagnosis of osteoporosis or pathological fracture were excluded. A stepwise multivariate logistic regression analysis was performed to identify factors associated with an in-hospital complication. RESULTS During the study period, 10,177 patients with a nonosteoporotic sacral fracture were identified, of whom 1002 patients underwent surgery. Between 2002 and 2011, the estimated incidence of sacral fractures increased from 0.67 per 100,000 persons to 2.09 (P < 0.001). Similarly, the rate of surgical treatment for sacral fractures increased from 0.05 per 100,000 persons in 2002 to 0.24 per 100,000 in 2011 (P < 0.001). Complications occurred in 25.95% of patients and remained steady over time (P = 0.992). Average length of stay significantly decreased from 11.93 days to 9.66 days in the 10-year period (P = 0.023). The independent factors associated with an in-hospital complication were congestive heart failure (odds ratio, 3.65; 95% confidence interval, 1.18-11.26), coagulopathy (odds ratio, 3.58; 95% confidence interval, 1.88-6.81), and electrolyte abnormalities (odds ratio, 3.28; 95% confidence interval, 2.14-5.02). CONCLUSION During the examined 10-year period, both the incidence of nonosteoporotic sacral fractures and the surgical treatment of these lesions increased in the United States. Between 2002 and 2011, although patient comorbidity increased, in-hospital complication rates remained stable and length of stay significantly decreased over time. LEVEL OF EVIDENCE 4.
Anterograde conduction to the His bundle during right ventricular overdrive pacing distinguishes septal pathway atrioventricular reentry from atypical atrioventricular nodal reentrant tachycardia

Background Distinguishing orthodromic atrioventricular reciprocating tachycardia (ORT) using a retrograde septal accessory pathway (AP) from atypical atrioventricular nodal reentrant tachycardia (AVNRT) may be challenging. Specifically, excluding the presence and participation of an AP may require multiple diagnostic maneuvers. Objective The purpose of this study was to assess the relative value of commonly used right ventricular (RV) pacing maneuvers, including identification of anterograde His-bundle activation with entrainment, to differentiate ORT using a retrograde septal AP from atypical AVNRT. Methods From March 2009 to June 2014, 56 patients (28 female; age 43.9 ± 17.4 years) who underwent electrophysiologic study and ablation for supraventricular tachycardia (26 ORT using septal AP and 30 atypical AVNRT) that exhibited a concentric atrial activation pattern and a septal ventriculoatrial interval >70 ms were analyzed. Results Overdrive pacing maneuvers or ventricular extrastimuli failed on at least 1 occasion to correctly identify a septal AP. Overall, 16 ORT patients and 26 AVNRT patients had successful RV entrainment, and 12 (75%) ORT patients showed anterograde His capture (11 patients) and/or anterograde septal ventricular capture (3 patients). None of the patients with atypical AVNRT showed anterograde conduction to the His bundle with entrainment. Conclusion RV pacing maneuvers are useful to exclude an AP in patients with AVNRT having concentric atrial activation sequence and a septal ventriculoatrial interval >70 ms; however, none are consistently diagnostic. When observed in this patient population, anterograde His-bundle or septal ventricular capture during RV entrainment was diagnostic for ORT using a septal AP.
Corticospinal Reorganization after Locomotor Training in a Person with Motor Incomplete Paraplegia

Activity-dependent plasticity as a result of reorganization of neural circuits is a fundamental characteristic of the central nervous system that occurs simultaneously in multiple sites. In this study, we established the effects of subthreshold transcranial magnetic stimulation (TMS) over the primary motor cortex region on the tibialis anterior (TA) long-latency flexion reflex. Neurophysiological tests were conducted before and after robotic gait training in one person with a motor incomplete spinal cord injury (SCI) while at rest and during robotic-assisted stepping. The TA flexion reflex was evoked following nonnociceptive sural nerve stimulation and was conditioned by TMS at 0.9 TA motor evoked potential resting threshold at conditioning-test intervals that ranged from 70 to 130 ms. Subthreshold TMS induced a significant facilitation on the TA flexion reflex before training, which was reversed to depression after training with the subject seated at rest. During stepping, corticospinal facilitation of the flexion reflex at early and midstance phases before training was replaced with depression at early and midswing followed by facilitation at late swing after training. These results constitute the first neurophysiologic evidence that locomotor training reorganizes the cortical control of spinal interneuronal circuits that generate patterned motor activity, modifying spinal reflex function, in the chronic lesioned human spinal cord.
A molecular basis for functional peptide mimicry of a carbohydrate antigen.

Peptides may substitute for carbohydrate antigens in carbohydrate-specific immunological reactions. Using the recognition properties of an anti-Lewis Y (LeY) antibody, BR55-2, as a model system, we establish a molecular perspective for peptide mimicry by comparing the three-dimensional basis of BR55-2 binding to LeY with the binding of the same antibody to peptides. The peptides compete with LeY, as demonstrated by enzyme-linked immunosorbent assay and Biacore analysis. The computer program LUDI was used to epitope map the antibody-combining site, correlating peptide reactivity patterns. This approach identified amino acids interacting with the same BR55-2 functional residue groups that recognize the Fucα(1–3) moiety of LeY. Molecular modeling indicates that the peptides adopt an extended turn conformation within the BR55-2 combining site, serving to overlap the peptides with the LeY spatial position. Peptide binding is associated with only minor changes in BR55-2, relative to the BR55-2-LeY complex. Anti-peptide serum distinguishes the Fucα(1–3) from the Fucα(1–4) linkage, therefore differentiating difucosylated neolactoseries antigens. These results further confirm that peptides and carbohydrates can bind to the same antibody-binding site and that peptides can structurally and functionally mimic salient features of carbohydrate epitopes.
Bioecology ofZaniothrips ricini Bhatti (Panchaetothripinae: Terebrantia: Thysanoptera) — A new thrips pest of castor (Ricinus communis: Euphorbiaceae)

Studies onZaniothrips ricini relating to sexual and parthenogenetic reproduction, life cycle, soil pupation, effect of RH and temperature on pupation as well as the three types of migration (i) plant to soil (ii) soil to plant (iii) plant to plant and within plants are discussed. Periodicity of infestation on the castor plant as well as the alternative hostsDatura stramonium andCalotropis gigantean have also been highlighted. The roles of the mantid predatorHaldwania lilliputana and the larval parasiteCeranisus menes are also indicated.
The effects of free recall testing on subsequent source memory

The testing effect is the finding that prior retrieval of information from memory will result in better subsequent memory for that material. One explanation for these effects is that initial free recall testing increases the recollective details for tested information, which then becomes more available during a subsequent test phase. In three experiments we explored this hypothesis using a source-monitoring test phase after the initial free recall tests. We discovered that memory is differentially enhanced for certain recollective details depending on the nature of the free recall task. Thus further research needs to be conducted to specify how different kinds of memorial details are enhanced by free recall testing.
Advances in nanofibrous scaffolds for biomedical applications: From electrospinning to self-assembly

Summary Increased understanding of the nanoscale structural features of the extracellular matrix (ECM) in directing cell and tissue function has led to the development of materials with nanofibrous architectures to mimic the biophysical cues of natural ECM. This review briefly discusses the importance of structural features within ECM and then examines the techniques that researchers have developed to recreate these structural features in materials. In particular, techniques including electrospinning, phase separation, and self-assembly are discussed in detail for their ability to fabricate nanofibrous scaffolds with various chemical and structural features. Advances in biomedical applications of nanofibrous scaffolds are highlighted with a particular focus on more recent studies to illustrate the current state of the field.
Numerical study of free-electron lasers with reversed guide field

Numerical studies of the high efficiency results recently reported by Conde and Bekefi for a reversed field FEL are presented. These studies indicate that the predicted saturated power is rather sensitive to the detailed model used of the space-charge forces. The reported results for Group I FEL operation can be reproduced by increasing the emittance by 45% compared with the reversed field case. In this regime particle loss, rather than trapping, is the saturation mechanism. The Group II results are not consistent with the single-frequency model. A two- frequency model has been developed to study the influence of competition between the modes of the upper and lower FEL intersections. Initial results from this model indicates that the low power in the Group II experiment is not a consequence of mode competition.
Feasibility of a search for planets around solar-type stars with a polarimetric radial velocity meter

Abstract A method of wavelength calibration is proposed which may enable measuring changes in radial velocity of bright solar-type stars to an accuracy of about 5 meters per second. Such accuracy would be sufficient for detecting Jupiter-like planets around these stars. The stellar spectrum is imaged by a slitless echelle spectrograph onto a 100-channel Digicon image tube. Instrumental profiles of Digicon diodes are narrowed down by a Fabry-Perot etalon, making the profiles less dependent on atmospheric seeing. The spectrograph and the etalon act merely as a series of narrow band filters for the individual diodes; effective wavelengths of these “filters” are monitored by a crystal retarder (phase retardation plate) kept at a constant temperature. For artificially linearly polarized stellar light which passes through this retarder and through a quarter-wave plate, the plane of polarization varies rapidly with wavelength. The precisely measured position angle of polarization provides wavelength calibration for every resolution element in the spectrum.
Scattering of Polarized Leptons at High Energy

A unified treatment is given of the high-energy elastic and inelastic electromagnetic scattering of electrons and muons by hadrons in terms of the polarization density matrix of the virtual photon exchanged. It is shown that when the leptons are longitudinally polarized, the virtual photon is in a pure polarization state which is a coherent superposition of an elliptically polarized transverse state and a longitudinal state. Experiments utilizing these features are suggested and the formulas for the cross sections are obtained. The limit in which the virtual photon is almost real is investigated carefully. Finally, it is shown that the formalism is immediately applicable to neutrino scattering.
Latitudinal effect in semiannual variation of geomagnetic activity

[1] The study of the semiannual variation in both geomagnetic activity indices and raw geomagnetic field data at a large number of geomagnetic observatories showed a dramatic decrease in the relative magnitude of this variation from low to high latitudes. While the semiannual variation in the Dst index at low latitudes is about 3 times, for the midlatitude Ap and Am indices it is only about 20–30%, and the auroral electrojet AE index and polar cap PCN index show a very small or no semiannual variation. The study of auroral electrojet AU and AL indices showed that the semiannual variation is evident in AL index and not observed in AU index. Although relative magnitudes of the semiannual variation in geomagnetic activity indices are strongly reduced at high latitudes, absolute magnitudes of these variations in the Dst, Ap, Am, and AL indices are approximately the same. The semiannual variation in geomagnetic field H component consists of two equinoctial minima probably caused by the increasing westward ring current and substorm westward auroral electrojet in equinoctial months. The additional analysis of raw geomagnetic field data from geomagnetic observatories in two hemispheres confirmed the results inferred from the study of geomagnetic indices. Meanwhile in the polar caps, the semiannual variation in raw geomagnetic data showing a strong decrease in geomagnetic field H component reveals a strong increase in the Z component which also might be caused by increasing the ring current and westward auroral electrojet during enhanced geomagnetic activity occurring in equinoctial months. It was also found that the amplitude of the semiannual variation at all latitudes increased significantly with increasing geomagnetic activity.
Spectroscopic Investigation of the Metal Ligation and Reactivity of the Ferrous Active Sites of Bleomycin and Bleomycin Derivatives

The geometric and electronic structures of high-spin ferrous complexes of bleomycin (FeIIBLM) and a series of systematically perturbed BLM derivatives have been investigated by optical absorption, circular dichroism (CD), and magnetic circular dichroism (MCD) spectroscopies. The active site of the unmodified drug complex is six-coordinate with the coordination sphere completed by at least five endogenous ligands including the pyrimidine, imidazole, deprotonated amide, and secondary and primary amine functionalities with either the 3-O-carbamoyl substituent of the mannose sugar or solvent bound at the sixth site. This weak sixth ligand is the exchangeable site of exogenous small molecule binding. Perturbing the carbamoyl substituent alters the coordination environment of the metal and decreases the azide binding affinities of the perturbed complexes. This is correlated with altered DNA cleaving capabilities. Additionally, altering the binding of the axial primary amine significantly affects the iron coordi...
Examination of esterases from insecticide resistant and susceptible strains of the German cockroach, Blattella germanica (L.)

Abstract Esterases from insecticide resistant and susceptible Blattella germanica (L.) were examined biochemically. Two strains were utilized: Johnson Wax (JWax; susceptible), and Munsyana (MA; chlorpyrifos LD 50 and LD 95 resistance ratio 5.2 and 10.0). On native polyacrylamide gel electrophoresis (PAGE), MA had four visible esterase electromorphs (El, E2, E3 and E4), whereas JWax had three (El, E2 and E4). Esterases E1 and E4 were more intense in the MA strain, and none of these esterase electromorphs were acetylcholinesterases. Insecticide inhibition of native esterases within polyacrylamide gels showed an interaction of all electromorphs with the carbamate insecticide propoxur and complete inhibition of all electromorphs by the carbamate bendiocarb and the organophosphate insecticides chlorpyrifos oxon, malaoxon and paraoxon. The pyrethroid insecticides permethrin and cypermethrin had no inhibitory effects. Sequential Q-Sepharose and hydroxyapatite column chromatography was used to fractionate esterases from each strain into two groups (I and II). Following hydroxyapatite fractionation of these esterase groups, inhibition kinetic constants ( k a and k 3 ), and molecular weights were estimated. Results for ka (the rate of enzyme inhibition) indicated a greater affinity for organophosphate insecticides by MA esterases. Results for k3 (the rate of enzyme recovery) indicated lengthened times of MA esterase-inhibition by organophosphate insecticides. Therefore the role, if any, in organophosphate resistance played by MA esterases must be by sequestration. Molecular weight estimates were within the range (55–65 kDa) previously observed for esterases from both B. germanica and Culex quinquefasciatus
Poststress glucose mitigates behavioral impairment in rats in the learned helplessness model of psychopathology

Three experiments examined the effects of poststress glucose treatment in the learned helplessness model of psychopathology in rats. In experiment 1, rats were given access to water or 40% aqueous glucose immediately following exposure to inescapable tailshocks or simple restraint in a 2 × 2 factorial design. Inescapably shocked rats failed to drink the glucose solution during the poststress interval and failed to show any improvement 24 hours after stress induction in shuttle-escape performance. Consequently, all rats received preexposure to a sweetened glucose cocktail in an attempt to increase poststress ingestion following inescapable shock treatment in experiment 2. Under these conditions, poststress intake of the glucose cocktail eliminated behavioral impairment in inescapably shocked rats relative to water-treated shocked rats and water- and glucose-treated restrained controls. Experiment 3 demonstrated that glucose prophylaxis occurs in the absence of sucrose when rats are preexposed to a 40% glucose solution prior to stress induction.
Vaginal birth after cesarean section: Results of a multicenter study

Abstract Cesarean section is now the most frequently performed major operation in the United States. Nearly one out of every four American babies is delivered by this operation. “Elective repeat” has become the most common indication for cesarean section. Although the safety of vaginal birth after cesarean section has been documented in several recent publications, automatic repeat cesarean section remains the rule in this country. We present one of the largest series of trial of labor ever reported. Of 57,553 live births, 4929 (8.6%) were of women with prior cesarean sections. Among 1776 patients who underwent a trial of labor, 1314 (74%) delivered vaginally. These was no maternal or perinatal mortality related to uterine scar rupture. Thus during the study period 1314 major operations were avoided. We conclude that, for the vast majority of women, allowing a trial of labor is a safe alternative to automatic elective repeat cesarean section
An Object Extraction Approach for Impervious Surface Classification with Very-High-Resolution Imagery

Detailed land cover maps provide important information for research and decision-making but are often expensive to develop and can become outdated quickly. Widespread availability of aerial photography provides increased accessibility of high-resolution imagery and the potential to produce high-accuracy land cover classifications. However, these classifications often require expert knowledge and are time consuming. Our goal was to develop an efficient, accurate technique for classifying impervious surface in urbanizing Wake County, North Carolina. Using an iterative training technique, we classified 111 nonmosaicked, very-high-resolution images using the Feature Analyst software developed by Visual Learning Systems. Feature Analyst provides object extraction classifications by analyzing spatial context in relation to spectral data to classify high-resolution imagery. Our image classification results were 95 percent accurate in impervious surface extraction, with an overall total accuracy of 92 percent. Us...
Effect of chronic castration on testosterone and estrogen binding to mouse kidney

Abstract The effects of prolonged castration on cytosol and nuclear androgen binding were studied in an attempt to explain the apparent resistance to androgen action observed in chronic castrates of various species. The mouse kidney was chosen for study because it is an androgen responsive tissue, extensively characterized, which does not atrophy following castration. Presence of estradiol receptors in the same tissue permitted us to compare the effects of castration on androgen and estrogen binding. Specific nuclear uptake of [3H]-testosterone was not different in kidney minces from 24 h, 1 week and 2 week castrate male mice. Four and 6 weeks after castration, however, a 2-fold increase in the number of available cytosol testosterone binding sites was observed. No changes in estrogen binding were found in chronically castrated male mice. Treatment with the nonaromatizable androgen, dihydrotestosterone, prevented these changes in androgen binding, whereas treatment with estradiol did not. These data indicate that androgen exposure is important in the regulation of androgen receptor activity in male mouse kidney. Whether the differences observed in prolonged castrates result from changes in receptor synthesis, processing or metabolism remains to be determined.
The Lyα forest at redshifts 0.1-1.6: good agreement between a large hydrodynamic simulation and HST spectra

We give a comprehensive statistical description of the Lyα absorption from the intergalactic medium in a hydrodynamic simulation at redshifts 0.1-1.6, the range of redshifts covered by spectra of quasi-stellar objects obtained with the Hubble Space Telescope (HST). We use the ENZO code to make a simulation in a 1024 3 cube with side length 76.8 Mpc comoving using 75-kpc cells, for a Hubble constant of 71 km s -1 Mpc -1 . The best prior work, by Dave et al., used a smoothed particle hydrodynamics simulation in a 15.6-Mpc box with an effective resolution of 245 kpc at the cosmic mean density and slightly different cosmological parameters. We use a popular cosmological model and astrophysical parameters that describe the ultraviolet background that photoionizes and heats the gas. At redshift z = 2 this simulation is different from data. Tytler et al. found that the simulated spectra at z = 2 have too little power on large scales, Lyα lines are too wide, there is a lack of high column density lines and there is a lack of pixels with low flux. Here we present statistics at z < 1.6, including the flux distribution, the mean flux, the effective opacity and the power and correlation of the flux. We also give statistics of the Lyα lines including the linewidth distribution, the column density distribution, the number of lines per unit equivalent width and redshift and the correlation between the linewidth and column density. We find that the mean amount of absorption in the simulated spectra changes smoothly with redshift as DA(z) = 0.0102(1 + z) 2.252 . Both the trend and absolute values are close to measurements of HST spectra by Kirkman et al. The column density distribution is the same as data at redshift 1.6, but at lower redshifts the simulation has fewer lines than data, perhaps because of issues making measurements in low signal-to-noise ratio spectra. The lines in data have smaller widths than in the simulation but again the data are not very reliable. We argue that these differences are probably not caused by lack of numerical resolution. Although these possible differences are larger than those that we saw at z = 2, overall, the simulation gives a good description of HST spectra at 0.1 < z < 1.6 given that we did not adjust either the parameters that we input to specify the simulations or the output from the simulation.
External optical feedback effects on intensity noise of vertical-cavity surface-emitting lasers

The authors have experimentally evaluated the effect of external optical feedback on the relative intensity noise (RIN) of a vertical-cavity surface-emitting laser (VCSEL) diode. In the absence of optical feedback, the smallest RIN is found to be -135 dB/Hz. For optical feedback levels approaching -25 dB, the RIN is degraded by about 20 dB. The authors have measured feedback-induced power penalties in a 500-Mb/s intensity-modulation/direct-detection (IM/DD) link and determined that the penalty exceeds 1 dB if the optical feedback ratio is larger than -30 dB. >
Umbilical Cord Blood (UCB) Transplantation: An Alternative to the Use of Unrelated Volunteer Donors?

Cryopreserved umbilical cord blood (UCB) from 4-6/6 HLA-A,B antigen and DRB1 allele matched unrelated neonatal donors contains sufficient numbers of hematopoietic stem cells (HSC) to engraft most younger pediatric patients with leukemia. Recent data demonstrate promising results in larger children and adults, as well as in patients with nonmalignant disorders. As a result, the number of UCB transplantations (UCBT) being performed is increasing dramatically. UCB has the clear benefits of rapid availability and a reduced stringency of requirement for HLA match. The latter attribute has the potential to extend the donor pool, which is of great importance for racial and ethnic minorities. Furthermore, new preparative regimens combined with double-unit grafts have been associated with improved engraftment and survival in larger children and adults, making UCBT a viable potential alternative to unrelated volunteer donor transplantation, especially in preference to transplantation using mismatched volunteers. This review summarizes the current status of unrelated donor UCBT and describes both the challenges and current areas of research associated with this HSC source.
Cardiorespiratory Effects of Added Dead Space in Patients With Heart Failure and Central Sleep Apnea

Background: Inhaled CO2 has been shown to stabilize the breathing pattern of patients with central sleep apnea (CSA) with and without congestive heart failure (CHF). Added dead space (DS) as a form of supplemental CO2 was effective in eliminating idiopathic CSA. The efficacy and safety of DS has not yet been evaluated in patients with CHF and CSA. Methods: We examined the respiratory and cardiovascular effects of added DS in eight patients with CHF and CSA. The DS consisted of a facemask attached to a cylinder of adjustable volume. During wakefulness, the cardiorespiratory response to 200 to 600 mL of DS was tested. Cardiac output and stroke volume were measured using echocardiography with and without DS. During the nocturnal study, patients slept with and without DS, alternating at approximately 1-h intervals. Results: Values are expressed as the mean SE. The wakefulness study revealed a plateau in the partial pressure of end-tidal CO2 (PETCO2) and the partial pressure of end-tidal O2 between DS amounts of 400 and 600 mL. The mean stroke volume index (33 7v s 34 7 mL/m 2 , respectively) and the mean cardiac index (1.9 0.3 vs 1.9 0.4 L/min/m 2 , respectively) were not affected by DS. Neither heart rate nor BP showed a significant change in response to DS of < 600 mL. During sleep, DS increased the PETCO2 (40.7 2.7 vs 38.9 2.6 mm Hg, respectively; p < 0.05), reduced apnea (1 1v s 29 7 episodes per hour, respectively; p < 0.01) and arousal (21 8v s 30 8 arousals per hour, respectively; p < 0.05), increased the mean arterial oxygen saturation (SaO2) [94.4 1.0% vs 93.5 1.1%, respectively; p < 0.01), and reduced SaO2 oscillations (SaO2 from maximum to minimum, 1.8 0.4% vs 5.5 0.9%, respectively; p < 0.01). Conclusion: DS stabilized CSA and improved sleep quality in patients with CHF without significant acute adverse effects on the cardiovascular function. (CHEST 2003; 123:1551–1560) Abbreviations: AHI apnea-hypopnea index; CHF congestive heart failure; CPAP continuous positive airway pressure; CSA central sleep apnea; DS dead space; Fetco2 fraction of end-tidal CO2 ;F ico2 fraction of inspired CO2 ;F io2 fraction of inspired O2 ;P etco2 partial pressure of end-tidal CO2 ;P eto2 partial pressure of
Defining market boundaries

This study shows how spatial information about product supply and demand can be used to determine the geographic extent of markets. It demonstrates that markets thus defined allow finer-grained measurement of competitive conditions than is possible using conventional approaches. Two procedures are developed and contrasted: one, called a natural market approach, is drawn from the Industrial Organization economics literature; the second, called an enactment approach, is associated with the open systems perspective on organizations. Applied to a set of hospitals in the San Francisco Bay area, geographic market boundaries established in these ways are shown to lead to finely defined markets, and to reveal strong variation in competitive conditions across the area ― variation not detectable if conventional approaches to market definition are used. It is shown that these approaches have applications beyond geographic market definition, and can also be applied to define markets in terms of product or service types.