cssi/SciSciGPT-SciSciNet huggingface dataset:
In vitro ovarian responses to pulsatile and continuous gonadotrophin administration on steroid secretion and oocyte maturation in the frogs, Rana pipiens and Rana catesbeiana

Abstract An in vitro superfusion system was used to study the relative effects of pulsatile and continuous gonadotrophin administration on steroid secretion and oocyte maturation in Rana pipiens ovaries. Pulsatile (10 min pulse/hr) delivery of pituitary extract (PE) resulted in a slightly (insignificantly) lower level of testosterone (T) secretion over a 12-hr period. Administration of a fivefold lower, subliminal amount of PE instead of hormone-free media between pulses did not change the pattern of T secretion. When the interpulse frequency was increased to 2 or 3 hr, there were notable oscillations in T secretion which corresponded to the peaks in luteinizing hormone associated with the PE. In four experiments ovarian fragments underwent oocyte maturation, but this occurred only in fragments that received continuous PE stimulation. Progesterone (P) secretion was measurable only when oocyte maturation was observed in the ovarian fragment. Rana catesbeiana ovarian fragments exposed to continuous superfusion with homologous PE produced more T than those receiving hourly pulses of PE over a 6-hr period. Oocyte maturation accompanied by P secretion was observed in one experiment under continuous, but not pulsatile administration of PE. These results suggest that the frog ovary may be more resistant than the mammalian ovary to “down-regulation” under continuous gonadotrophic stimulation. The implications of these results on the frog pituitary-gonadal axis are discussed.
Distractions, distractions: does instant messaging affect college students' performance on a concurrent reading comprehension task?

Abstract Instant messaging (IM) has become one of the most popular forms of computer-mediated communication (CMC) and is especially prevalent on college campuses. Previous research suggests that IM users often multitask while conversing online. To date, no one has yet examined the cognitive effect of concurrent IM use. Participants in the present study (N = 69) completed a reading comprehension task uninterrupted or while concurrently holding an IM conversation. Participants who IMed while performing the reading task took significantly longer to complete the task, indicating that concurrent IM use negatively affects efficiency. Concurrent IM use did not affect reading comprehension scores. Additional analyses revealed that the more time participants reported spending on IM, the lower their reading comprehension scores. Finally, we found that the more time participants reported spending on IM, the lower their self-reported GPA. Implications and future directions are discussed.
Calcium Induced Conformational Changes In The Cytoplasmic Tail Of Polycystin-2

Autosomal dominant polycystic kidney disease (PKD) is the most common, monogenic cause of kidney failure in humans, characterized by the presence of fluid filled cysts in kidneys, liver, pancreas and intestines. Most cases of PKD are linked with mutations in the genes Pkd1 or Pkd2, which encode proteins polycystin-1 (PC1) and polycystin-2 (PC2) respectively. Here we focus on PC2 a calcium (Ca2+) permeable channel in the transient receptor potential (TRP) channel family. PC1 and PC2 interact directly and this interaction is thought to be mediated by their cytoplasmic carboxyl terminal tails. The deletion of the carboxyl terminus of either PC1 or PC2 alters Ca2+ signaling; the most common pathogenic mutations in PC2 are premature truncations. We have previously identified two stable domains within the C-terminus of PC2. The first is an EF-hand Ca2+ binding domain. The second is a previously unreported coiled-coil domain which we show is responsible for oligomerization of PC2 using Small-Angle X-ray Scattering (SAXS), Analytical Ultracentrifugation and Size Exclusion Chromatography. We show by Isothermal Titation Calorimetry that the EF-hand domain binds Ca2+ and that mutations in the predicted Ca2+ binding loop abolish the affinity for Ca2+. We hypothesize that the EF-hand domain serves as a Ca2+ sensor/switch, and show that PC2 undergoes Ca2+ induced conformational changes by NMR, CD, and SAXS. We have completed NMR experiments necessary for high resolution structure determination in the presence and absence of Ca2+ and have identified PC2 residues with significant chemical shift changes upon Ca2+ titration. We have obtained crystals of the coiled coil domain of PC2 and are optimizing crystals for X-ray diffraction. Structure determination of these cytoplasmic domains will enable a structure-guided analysis of PC2 mediated Ca2+ signaling and further investigations into the molecular basis of PKD progression.
An electrophysiological analysis of the effect of phagostimulant mixtures on the responses of a deterrent-sensitive cell of gypsy moth larvae, Lymantria dispar (L.)

Gypsy moth larvae, Lymantria dispar (L.), are polyphagous feeders. The medial styloconic sensillum of this species bears a taste receptor cell that responds to alkaloids and another that responds to the sugar alcohol, inositol. The lateral styloconic sensillum bears a taste receptor cell that is sensitive to the sugar, sucrose. We tested the effect of two phagostimulants, namely sucrose and inositol, on the response of the deterrent-sensitive cell and found that both phagostimulants suppressed its response, equally, while their combination was significantly more effective. We also tested the effect of two alkaloids (i.e., strychnine and caffeine), which deter feeding in this species, on the response of the inositol- and sucrose-sensitive cells. Although both of these deterrents had no effect in suppressing the response of the sucrose-sensitive cell, they both had an effect in suppressing the inositol-sensitive cell. We also found that sucrose suppressed the response of the inositol-sensitive cell, whereas inositol had no significant effect on the response of the sucrose-sensitive cell. In this paper, we examined the effect of mixtures of these compounds to determine the nature of their interaction. In the context of host–plant interactions and, for example, host recognition, whereby host plant acceptability depends on the total sensory impression acquired from responses to multiple plant components rather than the presence or absence of single stimulant or deterrent compounds, this study could have a direct bearing in the development of natural compounds (i.e., alkaloids) for pest control and crop protection. It will also contribute to our understanding of the neural basis of the feeding behavior of this insect.
Fiber specklegram sensing with phase-conjugation

A multimode fiber specklegram sensor using phase-conjugate mirror is presented. This sensing technique is based on the phase compensation of phase-conjugate signal, which is very sensitive to external perturbation. The preliminary experiments on displacement measurement are also provided.
Psychological preparation of the patient and family

Psychological preparation is crucial, for it will contribute importantly to the patient's and family's ability to adapt to a diagnosis of urologic cancer and to manage the stresses of treatment. Psychological preparation is an intrinsic component of early doctor-patient interactions, whether or not the physician and patient perceive it as such. Guidelines for the pivotal discussion concerning diagnosis and treatment plan are provided. The results of a survey of psychosocial adaptation among 39 patients treated for seminomatous testicular cancer and 39 controls are presented. Patients were found to exhibit typical or average emotional status. They were significantly more satisfied than controls with spouse/partner relationships. Despite important sexual and reproductive limitations reported by others, patients treated for testicular cancer adapt well, and most attain average or better degrees of satisfaction with interpersonal and sexual relationships. Newly diagnosed patients, beginning their adjustment to what often appears to be an overwhelming set of problems and potential limitations, should benefit from the knowledge that psychosocial adaptation is an eventual reality. Physicians' management of early discussions, as well as their openness to ongoing communication, contribute importantly to the perspective that will guide patients and families through this process.
Comparing the value of fuel treatment options in northern Colorado's urban and wildland–urban interface areas

Abstract Urban and Wildland–urban interface (WUI) residents of two counties in Northern Colorado were surveyed to compare residents' values for forest fuels treatment programs. A Contingent Valuation Method (CVM) survey was designed and sent to sample each of four groups: Larimer County WUI, Larimer County urban, Boulder County WUI, and Boulder County urban. Logistic regression models were used to estimate willingness to pay (WTP) and to calculate the odds of voting in favor of each fuel treatment program. We found that residents differed with respect to income, proximity to forested areas, perceived wildfire risk, and attitudes regarding treatment programs. Mean WTP was higher for thinning than for prescribed burning among all four samples. Boulder County residents mean WTP was about 25% higher for both programs than Larimer county residents. These results have potential implications for forest management and policy decisions related to fuels treatments in forested areas at risk of wildfire.
A CHANGE IN THE BAR GENE OF DROSOPHILA INVOLVING FURTHER DECREASE IN FACET NUMBER AND INCREASE IN DOMINANCE

As part of a study of the factors controUingeye facet number in Drosophila melanogaster, selection has been carried on with a view to the determination of the germinal changes appearing during the course of selection. One of the most interesting of these changes occurred during the second generation of downward selection in the white bar stock. An exceptionally "low" male of this generation was shown to possess a changed gene with a marked increase in dominance. This individual appeared on November 20, 1917, and had but 19 facets, while the mean of its 62 brothers was 82.6 facets with a range of 41 to 134. With class sizes such that the range of a class is 10 per cent of its mean this represents a departure of -16.80 10 per cent class units from the mean of the males of the unselected bar stock, while the departure of the brothers of the mutant is on ly-3 .44 units. The new stock derived from the third hybrid generation of a mating of the mutant with a sister possesses the characteristics of the original male, and at the present writing (May 10, 1919) has remained without change for nearly 18 months except for the appearance of a few additional mutants. The name ultra-bar has been given to the new character. Its symbol, Bu, indicates that ultra-bar is a dominant allelomorph of bar. Full-eyed (wild-type) females at 27°C. have an average facet number of 810.6, bar females of the second low selected generation have 61.8 facets, and ultra-bar females 22.0 facets. The corresponding numbers for males are respectively 849.8, 75.6, and 23.0.
Correlation between hemodynamic parameters and intra-arterial septum motion in DeBakey type III aortic dissections using 2D pcMRI and 4D MRA

Outcome prediction in DeBakey Type III aortic dissections (AD) remains challenging. Large variations in AD morphology, physiology and treatment exist. A patient-specific approach towards a detailed understanding of the distinct features of each single case might be needed to account for this variation. In particular, an improved characterization of hemodynamic parameters in addition to geometrical quantities may yield deeper insight into this complex disease. Advances in cardiovascular magnetic resonance imaging (CMR) have resulted in pulse sequences that provide time-resolved information of blood velocities, aortic wall motion and, with the administration of exogenous intravenous contrast bolus, contrast passage timings. Here we provide a combined approach in a group of 10 AD patients using 2D phase contrast magnetic resonance imaging (2D pcMRI) and Time-resolved Angiography With Interleaved Stochastic Trajectories (TWIST) to quantify blood velocities, flow rates, maximum signal enhancement from exogenous contrast and time to maximum signal enhancement in the true lumen (TL) and false lumen (FL). The FL-TL dynamic pressure gradient was derived from 2D pcMRI velocity measurements. These hemodynamic parameters were correlated with dynamic parameters for the intra-arterial septum (IS) wall motion derived from 2D pcMRI. A strong positive correlation was found between the TL-FL dynamic pressure gradient and maximum IS extension (R=0.76) as well as with maximum IS contraction (R=-0.51) Taking the ratio of maximum extension to maximum contraction, the correlation increased to R= 0.81. The ratio of TL to FL volumetric flow rate showed a high correlation with the difference in FL-TL times to maximum enhancement (R=0.87) illustrating that higher flow in the TL will result in delayed contrast arrival in the FL and vice versa. Analogous, the TL to FL ratio of maximum enhancement correlated with the TL to FL ratio of the maximum volumetric flow rate (R=0.85). 2D pcMRI and 4D MRA in combination with exogenous intravenous contrast bolus allows characterization of hemodynamics in DeBakey type III AD. High correlations between IS wall motion, TL and FL pressure differences, flows and times to maximum enhancement were found. An extension of our analysis to follow-up imaging examinations are warranted to establish the potential for hemodynamic parameters determined with CMR as a marker for clinical outcome in longitudinal studies.
Pharmacological aspects of juglone

Abstract Juglone (5-hydroxy, 1-4 naphthoquinone), isolated from Juglans nigra (Black Walnut) in pure crystalline form has been investigated pharmacologically. These studies indicate that juglone is a depressant agent to unanesthetized fish, mice, rats and rabbits. It dilates the ear vessels of the intact rabbit and coronary arteries of the isolated rabbit heart. In spite of this dilatation juglone has no effect on the blood pressure and heart rate in the dog. It depresses the activity of isolated smooth muscle of rat intestine and uterus.
Markov Photographic Noise

Photographic noise is studied from the point of view of continuous-parameter Markov chains. A general, conditional-probability distribution of the undeveloped grains in a cell is used for a pure-death process. The corresponding mean and variance are obtained. A new theoretical expression relating rms density to average density is also determined. The application of this probability distribution to a typical photographic film is demonstrated and the informational sensitivity, defined for the effectiveness of information transmission, is also derived. Finally, it is concluded that the photographic process is nonhomogeneous in the sense that the probability of grain development (death) is a function of exposure time.
On the amplification of molecular fluctuations for nonstationary systems: hydrodynamic fluctuations for the Lorenz model

Abstract Using hydrodynamic fluctuation theory we develop quantitative expressions for describing the effect of thermal fluctuations on the Lorenz attractor. For typical liquids the initial exponential growth of fluctuations invalidates the deterministic equations of Lorenz within a matter of minutes. The saturation of the exponential growth is explored using an approximate nonlinear theory due to Kurtz. Analysis of the binning of long stochastic and deterministic trajectories shows that thermal fluctuations on the chaotic attractor are amplified by about two orders of magnitude.
The taming of Polos/Polis: Rhetoric as an achievement without woman

This essay describes how “rhetoric” came to be written historically in relation to woman's body. It shows how rhetoric, etymologically linked with both woman and horse, was progressively “tamed” into a non‐threatening force, and also how rhetoric/woman/horse simultaneously has resisted this taming. Using a collage procedure to cut and paste textual fragments of writing about rhetoric, the essay constructs an archetypal narrative plot that proceeds tropologically—metaphorically, metonymically, synecdochically, and ironcially—to domesticate and unleash rhetoric/woman/horse.
Racial and etiopathologic dichotomies in insulin hypersecretion and resistance in obese children

Objectives To assess insulin dynamics to oral glucose tolerance testing in obese children, denoting individual contributions of insulin hypersecretion versus resistance to racial and etiopathogenetic specificity. Study design We performed 3-hour oral glucose tolerance testing in 113 nondiabetic obese children (age 13.6 ± 3.1 years; 41 male, 78 female; 37 black, 41 white; 35 with central nervous system [CNS] insult). The corrected insulin response (CIRgp; measuring β-cell secretion) and the composite insulin sensitivity index (CISI) were computed and log-transformed, and each was modeled in terms of the other, plus race/etiology, age, sex, body mass index z score, glucose tolerance, pubertal status, and geographic location. Results A scatterplot of logCIRgp versus logCISI showed that racial and etiopathogenetic groups plotted in different areas. CISI (controlled for CIRgp and other variables) was only 13% lower in blacks than in whites (P = .32). Conversely, CIRgp (controlled for CISI and other variables) was 49% higher in blacks (P = .028). CNS insult exhibited a 40% higher CIRgp (P = .054) and 11% higher CISI (P = .42) than intact white subjects. Conclusions Insulin hypersecretion and resistance are distinct phenomena in childhood obesity. Insulin hypersecretion appears to be the more relevant insulin abnormality both in obese blacks and in CNS insult.
Craniofacial principles in face transplantation.

BACKGROUND Face transplantation allows the reconstruction of the previously nonreconstructible injury. Anthropometric landmarks are fixated to corresponding cephalometric landmarks to restore function and appearance, with emphasis on phonation, mastication, and functional upper airway. Currently, only a few face transplantations have been performed worldwide. A portion of these reconstructions involves combinations of hard and soft tissues of the midface. METHODS Craniofacial and orthognathic considerations should be emphasized for functional effect in the planning and execution of face transplants that include both bone and soft tissue elements. These steps are taken to restore normal anatomy by fixating the midface into proper relationship with the skull base. Traditional orthognathic planning, using cephalometric parameters, often involves a line through sella and nasion as a reference for the skull base. Intraoperatively though, without a cephalograph, the sella-nasion plane is not accessible as a reference point. RESULTS Postoperative analysis of our first face transplant recipient revealed that the Frankfort horizontal plane can alternatively serve as an accessible skull base reference point to guide the positioning of the midface. We have developed a technique to ensure fixation of the midface donor allograft in a proper functional relationship with the skull base, within 1 SD of Bolton normative data. CONCLUSIONS "Reverse craniofacial planning" allows for precise fixation of the hard tissue components of the face transplant in relation to the skull base, as opposed to a "best fit" approach. We believe that this relationship results in the most anatomical restoration of occlusion, speech, and airway function.
Validity of the longitudinal, expert, all data procedure for psychiatric diagnosis in patients with psychoactive substance use disorders

The longitudinal, expert, all data (LEAD) procedure has been employed as a criterion for the assessment of the procedural validity of diagnostic instruments. This study evaluated the procedure's concurrent, discriminant and predictive validity. Interview and questionnaire data obtained from 100 individuals in a substance abuse treatment program were used to assess current and lifetime substance use disorders and common comorbid disorders. An experienced, doctoral-level clinician formulated LEAD diagnoses for each patient, based on an initial interview, ongoing clinical contact and the results of the research assessment and all available clinical records. LEAD-derived substance use diagnoses showed good concurrent, discriminant and predictive validity. The validity of comorbid diagnoses obtained using the LEAD procedure was generally fair to good. Comparison with diagnoses based only on the clinician's unstructured initial interview showed that the availability of additional data enhanced diagnostic validity. Diagnoses derived by a research technician using the Structured Clinical Interview for DSM-III-R showed validity comparable to that of LEAD diagnoses. To enhance its diagnostic validity, applications of the LEAD standard should include a structured interview. Other variations in the application of the LEAD standard, including a longer evaluation period, may also enhance its performance as a diagnostic criterion measure.
A population-based study of IL4 polymorphisms in multiple sclerosis.

Abstract Previous studies have suggested a role for interleukin-4 gene ( IL4 ) in susceptibility to multiple sclerosis (MS) as well as other autoimmune diseases. We screened the promoter region, exons 1–4 and their splice sites for polymorphisms and tested the association between novel polymorphisms E1(33)*C→T and I3(2580)*C→A , and the established 5′(−523)*C→T and I3(709)*VNTR polymorphisms with susceptibility to, age of onset in, and course and severity of MS in sporadic cases. I3(709)*VNTR was associated with susceptibility to MS ( p =0.004) due to a dearth of heterozygotes in patients (29/122; 23.8%) compared to controls (91/244; 37.3%). Homozygotes for the uncommon I3(709)*allele-2 may have increased susceptibility ( p =0.044; OR=5.17, 95% CI: 0.83–54.95) as might carriers for the extended haplotypes 5′(−523)*T/E1(33)*T/I3(709)*allele-2/I3(2580)*C ( p =0.003; OR: 3.75, 95% CI: 1.18–11.93) or 5′(−523)*C/E1(33)*C/I3(709)*allele-1/I3(2580)*A ( p =0.004; OR: 4.22, 95% CI: 1.22–14.54). We could not confirm the previously reported association between carriage of I3(709)*allele-2 and older age of onset. However, we found a trend for association between the homozygous state for this allele and older age of onset.
An integrative approach to the biomechanical function and neuromuscular control of the fingers

The exquisite mechanical functionality and versatility of the human hand emerges from complex neuro-musculo-skeletal interactions that are not completely understood. I have found it useful to work within a theoretical/experimental paradigm that outlines the fundamental neuro-musculo-skeletal components and their interactions. In this integrative paradigm, the laws of mechanics, the specifications of the manipulation task, and the sensorimotor signals define the interactions among hand anatomy, the nervous system, and manipulation function. Thus, our collaborative research activities emphasize a firm grounding in the mechanics of finger function, insistence on anatomical detail, and meticulous characterization of muscle activity. This overview of our work on precision pinch (i.e., the ability to produce and control fingertip forces) presents some of our findings around three Research Themes: Mechanics-based quantification of manipulation ability; Anatomically realistic musculoskeletal finger models; and Neural control of finger muscles. I conclude that (i) driving the fingers to some limit of sensorimotor performance is instrumental to elucidating motor control strategies; (ii) that the cross-over of tendons from flexors to extensors in the extensor mechanism is needed to produce force in every direction, and (iii) the anatomical routing of multiarticular muscles makes co-contraction unavoidable for many tasks. Moreover, creating realistic and clinically useful finger models still requires developing new computational means to simulate the viscoelastic tendinous networks of the extensor mechanism, and the muscle-bone-ligament interactions in complex articulations. Building upon this neuromuscular biomechanics paradigm is of immense clinical relevance: it will be instrumental to the development of clinical treatments to preserve and restore manual ability in people suffering from neurological and orthopedic conditions. This understanding will also advance the design and control of robotic hands whose performance lags far behind that of their biological counterparts.
The Spatial Organization of a Local Labor Market: Employment and Residential Patterns in a Cohort of Engineering and Scientific Workers

A case study of the local labor market for engineers and scientists at three Lockheed plants in the Los Angeles metropolitan area is presented. The specifications of a questionnaire survey are described and a detailed statistical profile of questionnaire respondents is laid out. It is shown that the local labor market is highly concentrated in geographical space and that both job shifts and residence shifts of sampled workers tend to be extremely localized within the urban area. It is suggested that local labor markets with features like these are a source of significant agglomeration economies for employers.
Incidence of Transient Ischemic Attack in Rochester, Minnesota, 1985–1989

Background and Purpose—There is scant information available on the incidence of transient ischemic attack (TIA) in a defined population. This study defines incidence rates of first TIA and subtypes of TIA during 1985–1989 and compares the incidence to that obtained from a 1960–1972 cohort study. Methods—Medical records of all residents of Rochester with potential diagnosis of TIA during 1985–1989 were screened to determine whether the case met the criteria for TIA. All available data were used to determine the vascular distribution of the TIA. Average annual age- and sex-adjusted incidence rates were calculated for 1985–1989, and results were compared with incidence rates determined in a Rochester-based 1960–1972 cohort study. Results—Two hundred two cases of first TIA or amaurosis fugax occurred among Rochester residents during 1985–1989. The age- and sex-adjusted incidence rate for any TIA was 68/100 000 population. Incidence of amaurosis fugax was 13/100 000; anterior circulation (cerebral) TIA, 38/100...
The Impact of Sphingosine Kinase-1 in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) has a high reoccurrence rate and an extremely low survival rate. There is limited availability of effective therapies to reduce the rate of recurrence, resulting in high morbidity and mortality of advanced cases. Late presentation, delay in detection of lesions, and a high rate of metastasis make HNSCC a devastating disease. This review offers insight into the role of sphingosine kinase-1 (SphK1), a key enzyme in sphingolipid metabolism, in HNSCC. Sphingolipids not only play a structural role in cellular membranes, but also modulate cell signal transduction pathways to influence biological outcomes such as senescence, differentiation, apoptosis, migration, proliferation, and angiogenesis. SphK1 is a critical regulator of the delicate balance between proliferation and apoptosis. The highest expression of SphK1 is found in the advanced stage of disease, and there is a positive correlation between SphK1 expression and recurrent tumors. On the other hand, silencing SphK1 reduces HNSCC tumor growth and sensitizes tumors to radiation-induced death. Thus, SphK1 plays an important and influential role in determining HNSCC proliferation and metastasis. We discuss roles of SphK1 and other sphingolipids in HNSCC development and therapeutic strategies against HNSCC.
Synthese und Charakterisierung von Sulfinato‐Nickel(II)‐Komplexen

Synthese und Eigenschaften von Sulfinato-Nickel(II)-Komplexen des Typs L2Ni(Cl)SO2R (L2 = TMED, bipy, phen, DPPE, (PBu3)2; R = Ph, p-Tol, Me, NMe2) werden beschrieben. Die Charakterisierung der dargestellten Verbindungen erfolgte mit Hilfe magnetischer Messungen sowie der IR-und Reflexionsspektroskopie. Synthesis and Characterization of Sulfinato-Nickel(II) Complexes Synthesis and properties of sulfinato-nickel(II) complexes of the type L2Ni(Cl)SO2R (L2 = TMED, bipy, phen, DPPE, (PBu3)2; R = Ph, p-Tol, Me, NMe2) are described. The compounds obtained are characterized by means of magnetic measurements, i.r. and reflectance spectra.
Triply-ionized B2 molecules from a tandem accelerator

Abstract Beams of 10B3+2, 11B23+, and 10B11B3+ ions have been observed to emerge from a tandem accelerator. B2− mo into the accelerator, and positive ions emerging from the machine were analyzed for mass per charge and total energy. For 10B11B, intensities of singly-, doubly-, and triply-charged molecules were measured as a function of N2 gas pressure in the accelerator terminal stripper canal. These intensities were found to exhibit the same qualitative behavior for all charge states, with the number of triply-charged molecules a factor of ~ 2 × 10−4 less than for the doubly-charged molecules. No quadruply-ionized molecules were seen. The observation of particles corresponding to the breakup products of the multiply-ionized molecules indicates that these species were decaying in flight, and are apparently metastable with lifetimes of ~ μs. Comparisons are made between these observations and molecular orbital calculations.
Oxidative stress and the mechanical properties of naturally occurring chimeric collagen-containing fibers.

The byssal threads of marine mussels are a fiber-reinforced composite material. Fibers are continuous, separated by matrix, and consist of chimeric collagens that encompass within the same primary protein structure domains corresponding to collagen, polyhistidine, and either elastin or dragline spider silk. The elastic modulus (stiffness) of the proximal portion of byssal threads was measured by cyclic stress-strain analysis at 50% extension. Before measurement, the threads were conditioned by various treatments, particularly agitation in aerated or nitrogen-sparged seawater. Stiffness can be permanently increased by more than two times, e.g., from 25 MPa to a maximum of 65 MPa, by simple agitation in aerated seawater. Much but not all of this stiffening can be prevented by agitation under nitrogen. Reversible strain stiffening would seem to be a useful adaptation to lower residual stresses arising from the deformation of two joined materials, i.e., distal and proximal portions with rather different elastic moduli. The permanent strain stiffening that characterizes proximal byssal threads subjected to oxidative stress is probably due to protein cross-linking. In the short term, this results in a stronger thread but at the expense of dynamic interactions between the molecules in the structure.
Evaluation and Management of End-Stage Liver Disease in Children

End-stage liver disease in children presents a challenging array of medical and psychosocial problems for the health care delivery team. Many of these problems are similar to those encountered by caregivers of adults with end-stage liver disease, such as the development of complications of cirrhosis, including ascites, spontaneous bacterial peritonitis, and esophageal variceal hemorrhage. However, the natural history of disease progression in children and their responses to medical therapy can differ significantly from that of their adult counterparts. Children with end-stage liver disease are especially vulnerable to nutritional compromise; if not effectively managed, this can seriously impact long-term outcomes and survival both before and after liver transplantation. Moreover, close attention must be given to vaccination status and the clinical setting at which health care is delivered to optimize outcomes and the delivery of high-quality pediatric health care. In this review, we address important components of the evaluation and management of children with chronic end-stage liver disease.
Periapical abscesses of cut canine teeth in cynomolgus macaques

Periapical abscesses of canine teeth in a group of 47 male cynomolgus macaques are found to be associated with a procedure, involving cutting the canine teeth, used to make non-human primates less hazardous. Examination of 150 canine teeth in dry specimens revealed 30 cut teeth with no exposure of the pulpal chamber and 107 cut teeth where the dental pulp had been exposed. Of those teeth which had the pulpal chamber exposed by the cutting procedure, 85 (79·4%) showed clear evidence of osseous changes consistent with abscess formation in the apical regions.
NEED FOR A NEW COMMUTER CAR ENTRANCEWAY DESIGN FOR MIXED HIGH- AND LOW-LEVEL PLATFORMS

Serious problems result from the use of both high- and low-level station platforms on U.S. commuter railroads (especially common in the Northeast). These problems include long dwell times and resultant slower service, passenger (and employee) accidents and injuries, difficulties in complying with Americans with Disabilities Act (ADA) accessibility requirements, increased train crew size, and problems accommodating freight trains on tracks with high-level platforms. Various partial solutions to these problems have been proposed, and many are being used. However, no solution deals effectively with all of the problems. The benefits of a single, comprehensive solution are identified, including improved service, increased ridership and revenue, meeting ADA accessibility requirements, and reduced costs. To indicate the importance of a solution to these problems, and to encourage thinking about solutions, some order-of-magnitude estimates of these benefits are developed. Finally, one design for dealing simultane...
Urban Culture: City sex: views of American women and urban culture, 1869 to 1990

Urban women are provocative; their mere presence has frequently stimulated observers to label the relationship between women and urban culture problematic. As Mary P. Ryan recently noted, ‘To search for women in public is to subvert a longstanding tenent of the modern Western gender system, the presumption that social space is divided between the public and the private and that men claim the former while women are confined to the latter.’ What follows here is an examination of the changing discourse of the relationship between women and cities since the Civil War. Perhaps for the reason indicated by Ryan, few systematic surveys have been made of that literature. Only those works which explicitly posit a connection between women and urban culture are included here; it is not enough that the women described be in cities, there must be some discussion of the interaction between the two. The term ‘culture’ is used in the anthropological sense – culture as a way of life. Many of the works reviewed here examine women who somehow deviate from the ‘ideal’ woman, who in the nineteenth century seemed to be a married Protestant middle-class non-employed mother. Thus they demonstrate abundant interest in prostitutes, immigrant women and wage-earning women, as well as in politically and sexually radical women.
Thyrotropin receptor antibody assays: clinical utility.

In this issue of the Journal , Leschik and colleagues1 compare the analytical performance and the clinical utility of a commercially available thyroid-stimulating immunoglobulin (TSI) reporter bioassay with an automated thyrotropin-binding inhibitory immunoglobulin (TBII) electrochemiluminescent immunoassay. The TSI reporter bioassay is a cell-based assay (or “bioassay”) that uses a genetically engineered cell line capable of specifically detecting serum TSI using cyclic AMP–dependent luciferase activity as the readout. The TBII assay is an anti–thyrotropin receptor (TSHR) electrochemiluminescent immunoassay that uses a porcine TSHR and human anti-TSHR autoantibody M22. The authors report that the TSI bioassay is able to detect lower levels of anti-TSHR autoantibodies than the TBII assay and exhibits better precision, but they do not present data indicating whether either assay is more predictive than the other in determining patients’ responses to antithyroid treatment. However, they clearly establish the sensitivity of both assays. TSHR autoantibody (TRAb) measurements (as either TSI or TBII) generally have few potential clinical applications: confirming the diagnosis of Graves disease, the prediction of risk for Graves disease in a neonate born to a mother with Graves disease in pregnancy or in the past, and the prediction of relapse in the medical treatment of Graves disease. In most patients, the diagnosis of Graves disease can be made in the clinical setting of thyrotoxicosis, diffuse goiter, ophthalmopathy (exophthalmos), and dermopathy (pretibial myxedema).2,3 The diagnosis is easily confirmed in most patients with a low thyroid-stimulating hormone (TSH) concentration and an elevated FT4 concentration. In early Graves disease, if T4 levels are normal the …
A tissue phantom for investigating volume quantification on retinal images obtained with the Stratus OCT system

The performance of the Stratus OCT system in extracting shape and volume of retinal lesions was investigated by scanning a tissue phantom containing specific enclosed geometric gaps of known size. Measurements were made by filling the gaps with an aqueous suspension containing a fixed tissue suspended in phosphate-buffered saline inside the gaps. OCT raw data was exported for subsequent analysis using custom software written in MATLAB software platform. An active contour model was used to outline the boundaries of the fixed tissue on OCT images of the tissue phantom. Images provided by the OCT system were analyzed with the custom software and later compared with the actual geometric parameters of the tissue phantom. An active contour model is effective in detecting the boundaries of the tested object and accurately estimating its volume. We show that a tissue phantom provides an easy and reproducible method of verifying the accuracy and precision of specific features in the images retrieved by the Stratus OCT system.
Visit complexity, diagnostic uncertainty, and antibiotic prescribing for acute cough in primary care: a retrospective study

Background: Guidelines and performance measures recommend avoiding antibiotics for acute cough/acute bronchitis and presume visits are straightforward with simple diagnostic decision-making. We evaluated clinician-assigned diagnoses, diagnostic uncertainty, and antibiotic prescribing for acute cough visits in primary care. Methods: We conducted a retrospective analysis of acute cough visits – cough lasting ≤21 days in adults 18–64 years old without chronic lung disease – in a primary care practice from March 2011 through June 2012. Results: Of 56,301 visits, 962 (2%) were for acute cough. Clinicians diagnosed patients with 1, 2, or ≥3 cough-related diagnoses in 54%, 35%, and 11% of visits, respectively. The most common principal diagnoses were upper respiratory infection (46%), sinusitis (10%), acute bronchitis (9%), and pneumonia (8%). Clinicians prescribed antibiotics in 22% of all visits: 65% of visits with antibiotic-appropriate diagnoses and 4% of visits with non-antibiotic-appropriate diagnoses. Clinicians expressed diagnostic uncertainty in 16% of all visits: 43% of visits with antibiotic-appropriate diagnoses and 5% of visits with non-antibiotic-appropriate diagnoses. Clinicians expressed uncertainty more often when prescribing antibiotics than when not prescribing antibiotics (30% vs. 12%; p < 0.001). As the number of visit diagnoses increased from 1 to 2 to ≥3, clinicians were more likely to express diagnostic uncertainty (5%, 25%, 40%, respectively; p <0.001) and prescribe antibiotics (16%, 25%, 41%, respectively; p <0.001).
Feasibility, challenges, and performance of wireless multi-hop routing for feeder level communication in a smart grid

In a Smart Grid communication network at the power distribution level, several technologies have been suggested to meet communication needs. In this work these technologies are compared with an explanation of why wireless communication technologies may be most suitable. A wireless mesh network architecture is proposed to meet communication requirements of the power distribution system. Subsequently, a performance evaluation exploring connectivity and end-to-end delay when routing packets in this mesh architecture is done for the power grid topology. Optimizations are proposed to enhance overall communication performance, with specific recommendations made on node density, antenna transmission power levels, and application data rate.
Asymptotic generalized eigenvalue distribution of block Toeplitz matrices and application to space-time beamforming

In many detection applications, the main performance criterion is the Signal to Interference plus Noise Ratio (SINR). After linear filtering, the optimal SINR corresponds to the maximum value of a Rayleigh quotient, which can be interpreted as the largest generalized eigenvalue of two covariance matrices. In this paper, we extend the Szego's theorem for the generalized eigenvalues of Hermitian block Toeplitz matrices derived under the assumption of absolutely summable sequences. Then, we apply this result to wideband spacetime beamforming performance analysis where the optimal SINR can be interpreted as the largest generalized eigenvalue of a block Toeplitz matrices' pair. We show that the optimal space-time SINR converges to an upper bound that can be interpreted as an optimal zero-bandwidth spatial SINR and interpret this result for several jamming scenarios.
Histological and ultrastructural studies of secondary neurulation in mouse embryos

The histological and ultrastructural features of secondary neurulation in C57BL/6 mouse embryos were examined as a first step in the analysis of how this process occurs in mammalian embryos. Secondary neurulation involves two major events in mouse embryos: (1) formation of the medullary rosette (9.5- to 10-day embryos) or plate (11- to 12-day embryos), and (2) cavitation. These two events occur simultaneously. The medullary rosette consists of elongated tail bud cells, radially arranged around a central lumen formed by cavitation. The secondary portion of the neural tube forms in 9.5- to 10-day embryos by progressive enlargement of the central lumen and addition (by cell recruitment or mitosis) of tail bud cells to the rosette. The medullary plate likewise consists of elongated tail bud cells, but these cells do not surround a central cavity. Instead, cells of the medullary plate extend ventrad from the basal aspect of the dorsal surface ectoderm to a slit-like cavity formed by cavitation. Formation of the secondary neural tube occurs in 11- to 12-day embryos, principally by the recruitment of more lateral and ventral tail bud cells into the medullary plate. Free cells and cellular debris are frequently encountered in the forming lumen of the secondary neural tube, but cells exhibiting signs of necrosis were absent in cavitating regions. Numerous small intercellular junctions form at the inner ( juxtaluminal ) ends of tail bud cells as the medullary rosette or plate is forming and cavitation is occurring. These observations suggest that cavitation per se (i.e., formation of a lumen) during secondary neurulation is a relatively passive phenomenon, which results principally from neighboring cells becoming polarized apicobasally and incorporated into a primitive neuroepithelium. The latter constitutes the walls of the forming secondary neural tube.
Group sparse Lasso for cognitive network sensing robust to model uncertainties and outliers

a b s t r a c t To account for variations in the frequency, time, and space dimensions, dynamic re-use of licensed bands under the cognitive radio (CR) paradigm calls for innovative network-level sensing algorithms for multi-dimensional spectrum opportunity awareness. Toward this direction, the present paper develops a collaborative scheme whereby CRs cooperate to localize active primary user (PU) transmitters and reconstruct a power spectral density (PSD) map portraying the spatial distribution of power across the monitored area per frequency band and channel coherence interval. The sensing scheme is based on a parsimonious model that accounts for two forms of sparsity: one due to the narrowband nature of transmit-PSDs compared to the large portion of spectrum that a CR can sense, and another one emerging when adopting a spatial grid of candidate PU locations. Capitalizing on this dual sparsity, an estimator of the model coefficients is obtained based on the group sparse least-absolute-shrinkage-and-selection operator (GS-Lasso). A novel reduced-complexity GS-Lasso solver is developed by resorting to the alternating direction method of multipliers (ADMoM). Robust versions of this GS-Lasso estimator are also introduced using a GS total least-squares (TLS) approach to cope with both uncertainty in the regression matrices, arising due to inaccurate channel estimation and grid-mismatch effects, and unexpected model outliers. In spite of the non-convexity of the GS-TLS criterion, the novel robust algorithm has guaranteed convergence to (at least) a local optimum. The analytical findings are corroborated by numerical tests. Published by Elsevier B.V.
Lower All‐Cause, Cardiovascular, and Cancer Mortality in Centenarians' Offspring

Objectives To assess the cause of death for centenarians' offspring and controls. Design Cross-sectional study. Setting Community-based, nationwide sample. Participants Family pedigree information was collected on 295 offspring of centenarians (from 106 families with a parent already enrolled in the nationwide New England Centenarian Study) and on 276 controls (from 82 control families) from 1997 to 2000. Controls were individuals whose parents were born in the same year as the centenarians but at least one of whom died at the average life expectancy. Measurements Age at death and cause of death. Results Centenarians' offspring had a 62% lower risk of all-cause mortality (P Conclusion These findings suggest that centenarians' offspring have lower all-cause mortality rates and cause-specific mortality rates for cancer and coronary heart disease. These results suggest that mechanisms for survival to exceptional old age may go beyond the avoidance or delay of cardiovascular disease and also include the avoidance or delay of cancer. Moreover survival advantage of centenarian offsprings may not be due to factors related to childhood mortality. Ultimately, survival to exceptional old age may involve lower susceptibility to a broad range of age-related diseases, perhaps secondary to inhibition of basic mechanisms of aging.
Refractory period prolongation by biphasic defibrillator waveforms is associated with enhanced sodium current in a computer model of the ventricular action potential

Mechanisms through which biphasic waveforms lower defibrillation threshold are unknown. Previous work showed that low-intensity biphasic shocks (BS2), delivered during the refractory period of a control action potential (S1), produced significantly longer responses than monophasic shocks (MS2). To test the hypothesis that longer responses are due to hyperpolarization-induced excitation channel recovery during the first portion of the biphasic waveform, the authors used the Beeler-Reuter ventricular action potential computer model with the Drouhard-Roberge (BRDR) modification to study refractory period stimulation with MS2 (10 msec) and symmetrical BS2 (10 msec each pulse). At 1.5 times diastolic threshold, BS2 prolonged action potential duration when delivered 50 msec into the S1 refractory period, and produced a maximum BS2 versus MS2 response duration difference of 62 msec. Longer BS2 responses corresponded to enhanced BS2-induced sodium current compared to MS2. Maximum BS2 vs MS2 sodium current difference was 400 uA/cm/sup 2/. These results show that, in a computer model of the ventricular action potential, hyperpolarization by the first phase of a biphasic waveform enhances S2 sodium current and prolongs duration of refractory-period responses. This effectively shortens the cellular refractory period. Prolonged refractory period responses, produced by biphasic defibrillator waveforms, may underlie enhanced defibrillating efficacy at low shock intensities. >