cssi/SciSciGPT-SciSciNet huggingface dataset:
Responses of bat-prey to prescribed burns and mechanical thinning

Abstract Insects are an important aspect of forest and woodland ecosystems due to their role as prey for vertebrate species. Our research investigated the relationship between insects and forest management practices in the Ozark National Forest in Arkansas. We looked at the differences in biomass, abundance, and diversity of insects in 30 treatment stands with varying burn frequencies. Twelve of these stands were burned and mechanically thinned, 12 were only burned, and 6 were untreated. The burn frequencies of these stands range from being burned 0–4 times from 2007 to 2018. We deployed blacklight traps in each of the stands every month from mid-March to mid-November in 2019 to assess nocturnal bat prey. Over 30,070 insects were collected, with Lepidoptera being the most abundant order. Insects were dried, weighed, and identified for diversity metrics. We used multi-model selection and AICc to find the top models from a series of linear mixed effects models to determine the best forest management strategies for bat prey. Total nocturnal, aerial insect biomass, Lepidoptera biomass, and Macroheterocera abundance was lower in thinned stands. However, it is unclear if it is the removal of Lepidoptera tree hosts or changes to bat foraging activity that drove this relationship. Stands burned at high frequencies had a higher abundance of Coleoptera. The intermediate disturbance hypothesis was not supported with regards to Lepidoptera diversity and burn frequency. Burning at high frequencies (4 times per 12 years) and not thinning may be the best strategy for maximizing nocturnal Coleoptera and Lepidoptera, respectively.
Capacity Reservation for Intermittent Random Demand Surges: A Model for Cost Optimization in Cloud Computing

Over the last decade, adoption of cloud computing has been accelerating, while firms are struggling to manage their growing cloud spending in the face of demand surges caused by planned or random events including marketing campaigns, new-product introduction, and natural disasters. In general, a firm can purchase capacity through a standard reservation contract from the cloud providers, supplemented by on-demand capacity as well as capacity purchased through reservation contracts from the reserved-instance marketplace (like the one administered by Amazon Web Services) to deal with the demand surges. We first analyze a model where the firm knows the distributions of the surge magnitude and duration. We characterize the firm’s optimal decision on when to sell excess capacity in the marketplace, show that the optimal capacity levels are dependent on the pricing of the reserved instances and the cancellation fee, and devise a heuristic for determining the length of the supplementary contract. Furthermore, we examine a model extension with the Bayesian updating paradigm, whereby the firm has a prior estimate about the surge-demand distribution, and we propose a pragmatic policy that leverages the firm’s trade options to adjust the desired capacity levels as data unveils and the estimate is updated. Through a comprehensive numerical study with simulation, we find that, to deal with the demand surges, the firm should purchase more capacity through a supplementary contract with a longer duration, if the unit discount rate increases, the cancellation fee decreases, or the average surge and inter-surge durations increase. In such cases, the firm also benefits more from the flexibility of trade in the marketplace, and the benefits achieve the maximum if demand stays at the base and surge levels for almost equal durations. Therefore, our study provides both efficient optimization algorithms and valuable insights into the firm’s cloud capacity management practices.
Germanium: A review of its US demand, uses, resources, chemistry, and separation technologies

Abstract Germanium (Ge) is one of the critical elements of modern technologies, with supply risk, inefficient production, and increased demand. It is used in high technology applications such as infrared systems, fiber optics, polymer catalysis, electronics, and solar cells. Its demand is expected to increase due to lack of suitable substitutes, increasing demand for solar cells and 5G networks, and the continuous increasing trend of Ge demand for the past 20 years. Globally, 130 tonnes (t) of Ge are being produced (2020) primarily in China. Germanium is recovered as a byproduct from Zn-refineries and coal fly ash. Yet very low amount (
Racial differences in persistence to secondary prevention medication regimens after ischemic stroke

BACKGROUND Prior stroke is one of the biggest risk factors for future stroke events. Effective secondary prevention medication regimens can dramatically reduce recurrent stroke risk. Guidelines recommend the use of antithrombotic, antihypertensive and lipid-lowering medications after stroke. Medication adherence is known to be better in the presence of a caregiver but long-term adherence after stroke is unknown and disparities may persist. METHODS We examined the effects of race and sex on baseline prescription and maintenance of secondary prevention regimens in the presence of a caregiver using the Caring for Adults Recovering from the Effects of Stroke (CARES) study, an ancillary study of the national REasons for Geographic and Racial Differences in Stroke (REGARDS). RESULTS Incident ischemic stroke survivors (N = 172; 36% Black) with family caregivers had medications recorded at hospital discharge and on average 9.8 months later during a home visit. At discharge, antithrombotic prescription (95.9%), lipid-lowering medications (78.8%) and antihypertensives (89.9%) were common and there were no race or sex differences in discharge prescription rates. One year later, medication persistence had fallen to 86.6% for antithrombotics (p = 0.002) and 69.8% for lipid lowering (p = 0.008) but increased to 93.0% for antihypertensives (p = 0.30). Blacks were more likely to have discontinued antithrombotics than Whites (18.3% v 7.7%, p = 0.04). No significant differences in persistence were seen with age, sex, income, depression, or cognitive impairment. CONCLUSIONS Medication persistence was high in this sample, likely due to the presence of a caregiver. In our cohort, despite similar prescription rates at the time of hospital discharge, Black stroke survivors were more than twice as likely to stop antithrombotics than Whites. The effect of changes in patterns of medication usage on health outcomes in Black stroke survivors warrants continued investigation.
Learning Surgical Motion Pattern from Small Data in Endoscopic Sinus and Skull Base Surgeries

Existing studies demonstrated that surgical motion patterns are strongly correlated with surgical outcomes. Real surgeries are complicated and it is expensive to harvest surgical data. Consequently, existing researches on surgical motion patterns focus on specific concise surgical tasks or simple surgical procedures. The paper presents a surgical motion pattern modeling technique that uses small data but can be applied to virtually any Endoscopic Sinus and Skull Base Surgeries (ESSBSs). The proposed method decreases the dimensionalities of the feature space through projecting surgical instrument motions into the endoscope coordinate, based on human expert domain knowledge. Furthermore, the method uses kinematic features and learns the motion pattern with Gaussian Process learning techniques. Comparing with existing surgical motion pattern modeling methods, the proposed method: 1, learns the motion model from small data; 2, can be generally applied to ESSBSs because it neither assumes nor depends on specific surgical tasks; 3, provides informative results in a real-time manner for optimizing surgical motions for improving surgical outcomes. The proposed method was verified by predicting surgical skill levels on cadaver surgeries. The results show the real-time prediction precision is higher than 81% and the offline accumulated precision reach 100%.
Electrical Response of Shock-Wave-Compressed Ferroelectrics

Short duration electrical pulses with peak powers approaching a megawatt can be obtained by shock-wave compression of poled ferroelectric ceramics. The polarity of the electrical responses indicates that the physical process involved is not the piezoelectric effect but rather the destruction of the remanent polarization by either a randomization of domains or by a polymorphic phase transformation to a nonferroelectric State. Power supplies based on phase transformations are practical in that their electrical responses are relatively insensitive to the magnitude of the shock as long as the characteristic threshold conditions for the transformation are exceeded.
Novel phenotype associated with in vivo activated CTL precursors.

A previously undefined phenotype of CD8(+) cells that appears to represent in vivo activated CTL precursors (CTLP*) has been identified in the spleens of C57Bl/6 mice responding to a P815 tumor allograft. This population was first evident by the transient expression of very high levels of CD28 and CD44 on day 5 of the allograft response and reached maximal levels on days 7 and 8 before declining on day 9. A transient increase in CD69 expression was also observed on these cells on day 5. In contrast, CTL effectors (CTLE), identified by their CD8(+)CD44(hi)CD62LloCD45RBlo phenotype, were not appreciably detected in the spleen until day 8 and reached maximal levels on day 10. Further characterization of CTLP* on day 7 revealed that they represented blasting cells by increased light scatter and also expressed very high levels of CD54 but not CD122, CD152, or CD154. In addition, the cells had already up-regulated CD49d, asialo GM1, CD11a, and CD95L, and down-regulated their expression of CD62L. A small percentage of these cells also expressed CD25. Day 7 CTLP* sorted on the basis of their CD44(xhi) and CD54(xhi) phenotype did not exhibit cytolytic activity in a standard chromium release assay but became cytotoxic when they were cultured in the presence of exogenous murine IL-2 for 5 days. Granzyme B activity, however, was detected in CTLP* on day 7 at levels equivalent to CTLE on day 10. In order to establish a potential precursor relationship between CTLP* and CTLE, mice were treated with various doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a chemical that has been shown to dose-dependently suppress the in vivo generation of CTLE to P815 tumor cells by altering an early stage of CTLP activation. Results indicated that CTLP* were suppressed by TCDD on day 7 to the same degree that CTLE were suppressed on day 10. Importantly, for controls and for all doses of TCDD, there were approximately 12.5 CTLE on day 10 for every CTLP* detected on day 7. These results suggested that TCDD acted identically across all doses to inhibit the early stages of activation of CTLP but did not affect the final stages of differentiation and expansion to CTLE. This interpretation supports the previous observation that TCDD exposure had to occur within the first 3 days of the allograft response in order to induce suppression of CTLE activity. Taken together, these results support the conclusion that in vivo activated CTLP can be identified by their unique expression of very high levels of CD44, CD28, and/or CD54 prior to their full maturation and clonal expansion to functional CTLE.
The Depth/Breadth Tradeoff in Hierarchical Computer Menus

Goal acquisition speed and accuracy were compared for subjects using four different menu configurations of a semantic hierarchy on an interactive computer terminal. Depth (the number of menu levels...
Herpes Simplex Virus Products in Productive and Abortive Infection III. Differentiation of Infectious Virus Derived from Nucleus and Cytoplasm with Respect to Stability and Size

Abstract Approximately 67% of infectivity is associated with the nucleus 8 hr after productive infection of HEp-2 cells with herpes simplex virus. Comparison of nuclear and cytoplasmic infectious virus and macromolecular aggregates labeled with 3H-thymidine or with 3H-choline revealed the following. (i) Cytoplasmic infectious virus and macromolecular aggregates banded in CsCl at a density corresponding to enveloped nucleocapsids. The virus was relatively stable; there was only 50% loss of infectivity and only 16% of the virions became disaggregated. (ii) Nuclear macromolecular aggregates banded in CsCl solution at a density corresponding to unenveloped nucleocapsids and, moreover, both the infectious virus and aggregates were highly unstable. (iii) In sucrose density gradients, the nuclear macromolecular aggregates and infectivity sedimented as a single band and migrated more slowly than the corresponding cytoplasmic material. (iv) The infectivity of nuclear and cytoplasmic virus is readily inactivated by digestion with phospholipase C and with pronase. We conclude the following. (i) Cytoplasmic virus consists of enveloped nucleocapsids. (ii) Nuclear virus consists of nucleocapsids covered with lipid or partially enveloped. (iii) The molecular integrity of viral lipids is essential for infectivity. (iv) The envelope protects the nucleocapsid and accelerates adsorption to cells; it is not, however, inherently essential for infectivity.
High-Resolution Far Infrared Observations of SGR B2, W49, and DR21-W75

High resolution (∿20″) maps at 53μ and photometry at 53, 100, and 175μ are presented for the HII regions Sgr B2, W49, and DR21-W75. In general strong far infrared emission is coincident with HII condensations although several interesting exceptions are described. Simplified models are fit to the far infrared spectra to derive estimates of dust temperatures and optical depths. The models indicate that these sources have relatively large far infrared optical depths, ∿0.1 – 1 at 100μ, and temperatures of 30 – 50K. The amount of dust indicated by the far infrared emission is consistent with that expected in the massive molecular clouds seen in these sources.
β3A-adaptin, a Subunit of the Adaptor-like Complex AP-3

Recent studies have described a widely expressed adaptor-like complex, named AP-3, which is likely involved in protein sorting in exocytic/endocytic pathways. The AP-3 complex is composed of four distinct subunits. Here, we report the identification of one of the subunits of this complex, which we call β3A-adaptin. The predicted amino acid sequence of β3A-adaptin reveals that the protein is closely related to the neuron-specific protein β-NAP (61% overall identity) and more distantly related to the β1- and β2-adaptin subunits of the clathrin-associated adaptor complexes AP-1 and AP-2, respectively. Sequence comparisons also suggest that β3A-adaptin has a domain organization similar to β-NAP and to β1- and β2-adaptins. β3A-adaptin is expressed in all tissues and cells examined. Co-purification and co-precipitation analyses demonstrate that β3A-adaptin corresponds to the ∼140-kDa subunit of the ubiquitous AP-3 complex, the other subunits being δ-adaptin, p47A (now called μ3A) and ς3 (A or B). β3A-adaptin is phosphorylated on serine residues in vivo while the other subunits of the complex are not detectably phosphorylated. β3A-adaptin is not present in significant amounts in clathrin-coated vesicles. The characteristics of β3A-adaptin reported here lend support to the idea that AP-3 is a structural and functional homolog of the clathrin-associated adaptors AP-1 and AP-2.
Putting “Human Rights” Back into the U.N. Guiding Principles on Business and Human Rights: Shifting Frames and Embedding Participation Rights

This book contribution responds to an important and timely question: How, looking forward, can we take the U.N. Guiding Principles on Business and Human Rights (GPs) “beyond the end of the beginning,” ensuring that cumulative, step-by-step progress is in fact made in improving companies’ real-world and on-the-ground compliance with human rights standards? Finding the specific proposals made by the former SRSG John Ruggie, and largely echoed by the volume’s editors, wanting in this regard, the contribution recognizes the basis of those proposals as resting upon a highly inaccurate, but politically powerful, frame that has been widely promoted in international circles to defend the GPs and distance them from human rights NGOs. That frame serves not only to dramatically misrepresent the reasons human rights groups have been so uniformly critical of the GPs, but also, most consequentially, creates a cognitive frame that leads almost inevitably to proposed “intermediate pathways” forward that bear little relationship to the actual problems diagnosed. The piece argues that a new frame for situating international debate on the GPs is critically needed. Part I offers what the author sees as a far more accurate frame. Parts II and III then use this frame to rethink answers to the two key questions identified by the volume’s editors for constructively taking the GPs “beyond the end of the beginning”: How can “empowered civil society participation” effectively be incorporated into the GPs’ “dynamic logic”? And, what role, if any, does a human rights treaty instrument have to play?
A CMOS linear voltage/current dual-mode imager

We present a CMOS image sensor capable of both voltage- and current-mode operations. Each pixel on the imager has a single transistor acting as either source follower for voltage readout, or transconductor for current readout. The two modes share the same readout lines, but have their own correlated double sampling (CDS) units for noise suppression. We also propose a novel current-mode readout technique using a velocity-saturated short-channel transistor, which achieves high linearity. The 300/spl times/200 image array is a mixture of 3 types of pixels with identical photodiodes and access switches; while the readout transistors are sized for their designated mode of operation. This ensures a fair comparison on the performance of the different modes.
Repair of microvilli in the rat small intestine after damage with lectins contained in the red kidney bean

That microvilli of intestinal absorptive cells in the duodenum and jejunum are disrupted by acute challenge with lectins contained in raw kidney beans (RKB) was shown nearly 10 yr ago by light microscopy. However, the precise morphologic damage produced by RKB has not been characterized, and it is not known whether microvilli, once damaged, undergo repair. We have examined these issues by challenging rats with suspensions of 300 mg of RKB, boiled beans, or standard laboratory chow by orogastric lavage. Microvillus length was measured in electron micrographs from 6 to 20 h after challenge. Epithelial cell migration was determined by autoradiography after injection of [3H]thymidine. After challenge with RKB, microvilli (a) showed extensive vesiculation along the length of villi 2-4 h after challenge; (b) were reduced significantly in length along the entire villus 6 h after challenge; and (c) were near normal in length by 20 h after challenge. Microvillus length was also reduced significantly 6 h after challenge with boiled beans. The rate of cell migration was not accelerated by treatment with RKB. These data suggest that damage to microvilli caused by 300 mg of RKB is self-limited and reversible; microvilli once damaged by RKB are repaired. Repair of microvilli is due to intrinsic reparative processes rather than accelerated replacement of damaged cells. We speculate that microvilli may be repeatedly damaged and repaired after ingestion of dietary lectins.
Analysis of Isoflavones in Soy Foods

Increasing evidence suggests that consumption of soybean products may have a significant impact upon health. The biological activity has been associated, in part, with the presence of isoflavones in soy. Analysis of these bioactive compounds in soybean products is an essential part of any research involving soy isoflavones. Various processing conditions produce soy products with a wide range of isoflavone content and composition. Recent studies demonstrated that the chemical forms and abundance of isoflavones in soy foods have a significant impact on their bioavailability and biological effects. It is thus very important to avoid altering the natural forms and abundance of the twelve soy isoflavones during extraction, identification, and quantification. In this unit, an attempt has been made to provide reliable protocols with the most commonly used analytical techniques for this purpose.
Olfactory thresholds and level of anxiety

Absolute and difference thresholds of n-octanol were determined for 30 college students scoring at extremes of the Taylor Manifest Anxiety Scale. High-anxious Ss produced significantly higher absolute thresholds and more reversals than low-anxious Ss. In the difference threshold task, high-anxious Ss responded within a narrower area of uncertainty, but points of subjective equality did not differentiate the groups. Also, the number of low anxious reversals incr eased in the second task to a level similar to tha t of high anxious Ss. Absolute and difference thresholds were not correlated, and response latencies were comparable across groups and tasks. Results were discussed in terms of predictions derived from Hull’s multiplicative drive theory (Brown, 1961).
Effects of groundcover management on soil properties, tree physiology, foliar chemistry and growth in a newly established Fraser fir (Abies fraseri [Pursh] Poir) plantation in Michigan, United States of America

Incorporating cover crops into Christmas tree plantations may potentially improve soil fertility, tree growth and quality and be an alternative to commercial nitrogen (N) fertilizers. However, cover crops may compete with the trees for water and other nutrients than N. This study was carried out to assess whether soil fertility, tree survival and growth could be improved by incorporating leguminous and non-leguminous cover crops into the Fraser fir (Abies fraseri) production system. Dutch white clover (Trifolium pratense), alfalfa (Medicago sativa) and perennial ryegrass (Lolium perenne) were grown in a newly established Fraser fir plantation using two cover crop management practices; no banding (NB) by growing each cover crop throughout the entire plot and banding (B) by creating a 61 cm-wide bare zone centered on the tree rows. A conventionally-managed system (CONV) was used as a control. The cover crop aboveground biomass and N content were assessed. Soil available N (NO3 − and NH4 +) and N mineralization were measured at 0–15, 15–30 and 30–45 cm soil depths. Tree survival, growth, photochemical efficiency of photosystem II (Fv/Fm), branch water potential (Ψw) and foliar nutrients were also evaluated. Biomass production was as high as 13.9, 10.2 and 5.9 Mg DM ha−1 year−1 for clover, alfalfa and ryegrass, respectively. Cover cropping increased soil available N by 1.5- and 2.2-fold relative the CONV in the top soil layer in 2007 and 2008, respectively. Tree seedling survival and growth in the B and CONV systems were similar. In contrast, NB treatments resulted in poor seedling survival and growth relative to the B and CONV plots. Plant Ψw and Fv/Fm decreased significantly for A. fraseri seedlings on the NB treatments relative to their counterparts on the B and CONV plots. However, cover cropping had marginal effects on foliar nutrients. Cover cropping with banding can be an efficient strategy for maintaining productivity in Fraser fir Christmas plantations.
A free-ranging roundtable discussion on hypertension

During the Nineteenth Annual Scientific Meeting of the American Society of Hypertension in New York, NY, on May 20, 2004, a gathering of international hypertension experts was convened to discuss far-reaching aspects of researching and managing hypertension. Dr John Laragh of Cornell University, New York, NY, USA; presided. Additional participants were, in order of participation, Jean E Sealey, DSc, New York, NY, USA; Mark C Houston, MD, Nashville, TN, USA; Haralambos Gavras, MD, Boston, MA, USA; Richard J Johnson MD, Gainesville, FL, USA; Jon D Blumenfeld, MD, New York, NY, USA; Morris Brown, MD, Cambridge, England; John B Standridge, MD, Chattanooga, TN, USA; Brent M Egan, MD, Charleston, SC, USA; Jay I Meltzer, MD, New York, NY, USA; Tatsuo Shimosawa, MD, PhD, Tokyo, Japan; Hans R Brunner, MD, Lausanne, Switzerland; and Toshiro Fujita, MD, Tokyo, Japan. The following is not verbatim but instead represents a summary of key points made over a 3-h dinner discussion.
Making Online Learning Accessible Using Technology to Declutter the Web

The proliferation of Web 2.0 technologies has made it possible for teachers to create a variety of engaging online learning activities for students of all ages. However, for students with learning disabilities, the prospect of having to search, read, and analyze information online can be overwhelming. This article reviews a variety of tools and techniques that teachers can use to help make online learning more manageable for students with disabilities. These free tools focus on removing the clutter and distractions often found online and helping direct student attention towards the relevant content.
Surgical Management of Pancreaticobiliary Disease associated with Juxtapapillary Duodenal Diverticula: Case Series and Review of the Literature

Introduction Juxtapapillary duodenal diverticula (DD), although usually asymptomatic, are occasionally associated with pancreaticobiliary conditions such as recurrent bile duct stones, cholangitis, and pancreatitis.
Surface electromagnetic waves in chromium

Abstract The absorption of surface electromagnetic waves in Cr has been measured from 4K up to temperatures just above the Neel temperature T N = 312 K at a frequency large enough to excite electrons across the antiferromagnetic energy gap. The effect of the opening up of the gap immediately below T N may clearly be seen.
The incidence, volume, absorption, and timing of supratentorial pneumocephalus during posterior fossa neurosurgery conducted in the sitting position.

BACKGROUND: Supratentorial pneumocephalus (STP) is a known complication of neurosurgical procedures of the posterior fossa when conducted in the sitting position. Few studies have examined STP as differentiated from pneumocephalus in the operative field. METHODS: Ninety-five of 106 consecutive patients had postoperative radiographic studies and median nerve somatosensory evoked potential (SSEP) recording during surgery. STP was identified on postoperative skull films or computerized tomography (CT). STP volume was measured on CT scans. SSEP changes were identified in the monitoring records. RESULTS: STP was identified in 40 patients (42.1%). STP volume on CT scans within 4 hours of surgery ranged from 6 to 280 cm3 (cubic centimeters). An extraventricular drain or ventriculo-peritoneal shunt did not increase the incidence of STP (P=0.85). The absorption of STP in 5 patients with multiple CT scans showed an immediate reduction of 24% followed by exponential decay with an half life of 1.5 days. Four patients with an extraventricular drain or ventriculo-peritoneal shunt had excessive volume of STP when measured at 1 day or later. Six patients with significant SSEP amplitude reductions attributed to STP had volumes exceeding 90 cm3 on a CT scan within 4 hours of surgery. The onset of these changes occurred at various times from dural opening to closing. CONCLUSIONS: STP is common after posterior fossa neurosurgical procedures conducted in the sitting position. Further studies are needed to fully characterize the absorption of air and the timing of the entry.
The U.S. Patent classification system

The heart of the system utilized by the US Patent and Trademark Office for the storage and retrieval of technical information is a hierarchical scheme for the classification of patents based on the technical subject matter disclosed in them. Multiple copies of patents are stored in the system according to their classifications, and technical information is retrieved from the system be delineating fields of search in terms of classifications most apt to include all disclosures relevant to the subject matter to be retrieved.
Consumer and Trained Panels Versus the Veterinary Inspector on Wholesomeness of Poultry Carcasses

Abstract THE inspection of food for wholesomeness has never confined itself entirely to concern over hazards to human health. The criteria of wholesomeness in foods likewise has never been limited to this consideration alone. While the risk of infecting a consumer with a disease or in some manner causing his intoxication are the paramount concerns of wholesomeness, a multitude of other considerations also obtain. Foremost among these is probably sanitation or the conditions under which the food is prepared. Perhaps next in consideration is whether the food is adulterated or mixed with some material hazardous to or, at least, not expected by the ordinary consumer. In addition to these rather clear concepts, there are a number of other considerations which lack precise definition and for which adequate criteria have not been developed. These relate to such terms as repugnant, unsound, filthy, putrid, decomposed, abnormal, unfit for human food, and so on… .
Timing of Delivery and Pregnancy Outcomes Among Laboring Nulliparous Women

Objective The objective of the study was to compare pregnancy outcomes by completed week of gestation after 39 weeks with outcomes at 39 weeks. Study Design Secondary analysis of a multicenter trial of fetal pulse oximetry in spontaneously laboring or induced nulliparous women at a gestation of 36 weeks or longer. Maternal outcomes included a composite (treated uterine atony, blood transfusion, and peripartum infections) and cesarean delivery. Neonatal outcomes included a composite of death, neonatal respiratory and other morbidities, and neonatal intensive care unit admission. Results Among the 4086 women studied, the risks of the composite maternal outcome ( P value for trend P P = .047) increased with increasing gestational age from 39 to 41 or more completed weeks. Adjusted odds ratios (95% confidence interval) for 40 and 41 or more weeks, respectively, compared with 39 weeks were 1.29 (1.03-1.64) and 2.05 (1.60-2.64) for composite maternal outcome, 1.28 (1.05-1.57) and 1.75 (1.41-2.16) for cesarean delivery, and 1.25 (0.86-1.83) and 1.37 (0.90-2.09) for composite neonatal outcome. Conclusion Risks of maternal morbidity and cesarean delivery but not neonatal morbidity increased significantly beyond 39 weeks.
Luminescence of C60 adsorbed on Ag and In surfaces

Abstract The photoluminescence (PL) of 1–2 monolayers (ML) of C60 adsorbed on cold-deposited Ag and In surfaces is strongly quenched by the metal-C60 interaction. However, similar to the case of the Raman spectra of C60 on the same surfaces, the PL intensity increases substantially upon annealing of the surfaces of 300 K. Changes in the PL spectrum indicate that the metal-C60 interaction, which includes charge transfer from the surface to the adsorbed C60, perturbs the first C60 ML more strongly than the second. We attribute these effects to the introduction of nonradiative deexcitation channels involving electronic states near the metal's Fermi level.
Debromination of Polybrominated Diphenyl Ethers by Nanoscale Zerovalent Iron: Pathways, Kinetics, and Reactivity

The debromination of selected polybrominated diphenyl ethers (PBDEs) by nanoscale zerovalent iron particles (nZVI) was studied to investigate the degradation pathways and the reaction kinetics of the PBDEs. The primary PBDE investigated was 2,3,4-tribromodiphenyl ether (BDE 21) to assess degradation pathways. nZVI could effectively debrominate the selected PBDEs into lower brominated compounds and diphenyl ether, a completely debrominated form of PBDEs. The susceptibility of the meta-bromine by nZVI was observed from the debromination tests for PBDEs with single-flanked (2,3-diBDE and 3,4-diBDE) and unflanked (three mono-BDEs) bromines. The stepwise debromination from n-bromo- to (n-1)-bromodiphenyl ether was observed as the dominant reaction process, although simultaneous multistep debromination seemed to be plausible for di-BDEs having two bromines adjacent on the same phenyl ring. The reaction rate constants were estimated by assuming the reaction between PBDEs and nZVI was a pseudo-first-order reaction and the rates decreased with fewer bromine substituents. The reaction rate constants were correlated with the heat of formation and the energy of the lowest unoccupied molecular orbital of the corresponding compounds, and these appear to be useful descriptors of relative reaction rates among PBDE homologue groups.
The absorption spectrum of HNF in the region 3800–5000 Å

Abstract An absorption spectrum occurring in the region 3800–5000 A, obtained in the flash photolysis of HNF 2 , was investigated at high resolution. The main conclusions of earlier workers are confirmed, namely that the absorption is due to a type- C transition of the HNF molecule, which is bent in both ground and excited states. The bond angles for the two states are 105 and 125°, respectively. Seven members of a progression in the upper-state bending frequency are observed. Axis-switching effects accompanying the large change in bond angle generate prominent s Q - and q Q -branches. Most of the rotational lines are resolved into spin-doublets, and the splitting pattern provides an excellent example of the effects of spin-rotation interaction in a nearly-symmetric top. The spin-rotation coupling constants in the two states indicate that the correlate with the same 2 Π state of the linear molecule. The previously suggested possibility, that the off-diagonal elements of the spin-rotation coupling tensor might not be symmetrical, is considered, and matrix elements for the skew-symmetric part of the tensor are given. The 010-000 band shows evidence of rotational coupling between the vibrations ν 2 and ν 3 which is diagonal in N and K and proportional to K 2 . The theory of this type of coupling is developed.
Dimension of the crown Skn

In 1941, Dushnik and Miller introduced the concept of the dimension of a poset (X, P) as the minimum number of linear extensions of P whose intersection is exactly P. Although Dilworth has given a formula for the dimension of distributive lattices, the general problem of determining the dimension of a poset is quite difficult. An equally difficult problem is to classify those posets which are dimension irreducible, i.e., those posets for which the removal of any point lowers the dimension. In this paper, we construct for each n>=3, k>=0, a poset, called a crown and denoted S^k"n, for which the dimension is given by the formula [email protected]?(n+k)(k+2). Furthermore, for each t>=3, we show that there are infinitely many crowns which are irreducible and have dimension t. We then demonstrate a method of combining a collection of irreducible crowns to form an irreducible poset whose dimension is the sum of the crowns in the collection. Finally, we construct some infinite crowns possessing combinatorial properties similar to finite crowns.
Development and validation of k-nearest-neighbor QSPR models of metabolic stability of drug candidates.

Computational ADME (absorption, distribution, metabolism, and excretion) models may be used early in the drug discovery process in order to flag drug candidates with potentially problematic ADME profiles. We report the development, validation, and application of quantitative structure−property relationship (QSPR) models of metabolic turnover rate for compounds in human S9 homogenate. Biological data were obtained from uniform bioassays of 631 diverse chemicals proprietary to GlaxoSmithKline (GSK). The models were built with topological molecular descriptors such as molecular connectivity indices or atom pairs using the k-nearest neighbor variable selection optimization method developed at the University of North Carolina (Zheng, W.; Tropsha, A. A novel variable selection QSAR approach based on the k-nearest neighbor principle. J. Chem. Inf. Comput. Sci., 2000, 40, 185−194.). For the purpose of validation, the whole data set was divided into training and test sets. The training set QSPR models were charact...
The Nature of the Solid Reaction Product from Tri-(p-Tolyl) Amine and Antimony Pentachloride

Abstract X-ray powder diffraction studies of the solid isolated from interaction of tri-(p-tolyl) amine (TTA) and SbCl5 establish that this material consists of more than one crystalline phase, a consequence of the reactivity of SbCl6 − toward TTA.
Androgen Biosynthesis and Secretion in Developing Xenopus laevis

Abstract In the frog, Xenopus laevis , castration or anti-androgen treatment during the late tadpole or early juvenile stages blocks masculinization of vocal neuroeffectors in males while exogenous androgen or a testicular transplant masculinizes vocal neuroeffectors in females. To elucidate the relation between androgen secretion and the process of masculinization, we measured androgen by radioimmunoassay in adults, juveniles, and tadpoles. In adult females, values for both testosterone (T) and dihydrotestosterone (DHT) were essentially identical during the winter and the summer while in males, summer values for both androgens were 7 to 8x winter values. For DHT, circulating values in males significantly exceeded those in females in both winter and summer while for T, values differed significantly only in summer. Sex differences in circulating androgen arise at late juvenile stages (PM4 and PM5); T values are higher in males than in females and higher, for both sexes, in winter than in summer. During early juvenile stages (PM1-PM3), there were no seasonal or sex differences in circulating androgens. While androgens were detected in liver during late tadpole stages (stage 56-66), no sex differences were apparent. Androgens can be detected in tadpole tissues as early as tadpole stage 47. Δ5-3β-Hydroxysteroid dehydrogenase (HSD) histochemistry indicates that tadpole gonads and interrenals (and, to a much lesser extent, kidneys) are the only tissues capable of steroid biosynthesis. Interrenal HSD activity was present throughout tadpole development; in gonads, activity began before sexual differentiation. Thin-layer chromatographic separation of steroid metabolits following in vitro incubation with radioactive precursors indicated that the interrenals were more active than the gonads in tadpoles but not in juveniles. Thus, interrenals and gonads of developing X. laevis can synthesize Δ4 steroids (which include androgens) and, from early tadpole stages, are capable of metabolizing pregnenolone and testosterone, early and late compounds in the steroid synthetic pathway, respectively. The absence of dramatic sex differences in T or DHT levels during late tadpole and early juvenile stages suggests that while necessary, androgen secretion is not sufficient for masculinization of vocal neuroeffectors.
Post-Transcriptional Regulation of Chemokine Receptor CXCR4 by Estrogen in HER2 Overexpressing, Estrogen Receptor-Positive Breast Cancer Cells

Expression of the chemokine receptor CXCR4, a G protein-coupled receptor, and HER2, a receptor tyrosine kinase, strongly correlates with the aggressive and metastatic potential of breast cancer cells. We studied estrogen regulation of CXCR4 in estrogen receptor (ER)-positive MCF-7 breast cancer cells overexpressing HER2 (MCF7-HER2). Although estrogen evoked no change in CXCR4 mRNA levels, CXCR4 protein was significantly up-regulated after estrogen treatment of these cells, whereas estrogen had no effect on CXCR4 protein level in parental MCF7 cells that are low in HER2. Use of the CXCR4 specific inhibitor, AMD 3100, indicated that this increase in CXCR4 protein was partially responsible for the increase in estrogen-induced migration of these cells. The estrogen-induced increase in CXCR4 protein in MCF-7-HER2 cells was abrogated by the antiestrogen ICI 182780 and by gefitinib (Iressa; a phospho-tyrosine kinase inhibitor), indicating an ER-mediated effect and confirming involvement of receptor tyrosine kinases, respectively. Using specific pathway inhibitors, we show that the estrogen-induced increase in CXCR4 involves PI3K/AKT, MAPK and mTOR pathways. PI3K/AKT and MAPK pathways are known to result in the phosphorylation and functional inactivation of tuberin (TSC2) of tuberous sclerosis complex thereby negating its inhibitory effects on mTOR, which in turn stimulates the translational machinery. Small interfering RNA (siRNA) mediated knockdown of tuberin elevated the level of CXCR4 protein in MCF7-HER2 cells and also nullified further estrogen up-regulation of CXCR4. This study suggests a pivotal role of PI3 K, MAPK and mTOR pathways, via tuberin, in post-transcriptional control of CXCR4, initiated through estrogen-stimulated crosstalk between ER and HER2. Thus, post-transcriptional regulation of CXCR4 by estrogens acting through ER via kinase pathways may play a critical role in determining the metastatic potential of breast cancer cells.
Comparison of blood ethanol levels by gas-liquid chromatography, chemical titration, and enzymatic oxidation.

(1971). Comparison of Blood Ethanol Levels by Gas-Liquid Chromatography, Chemical Titration, and Enzymatic Oxidation. Clinical Toxicology: Vol. 4, No. 2, pp. 217-224.
Predecessors of the IEEE Control Systems Society

This short article outlines events leading to the formation of the Professional Group on Automatic Control (PGAC) of the Institute of Radio Engineers (IRE)-a predecessor of the IEEE Control Systems Society.
Formation of pyrophosphate on hydroxyapatite with thioesters as condensing agents

'Energy-rich' thioesters are shown to act as condensing agents in the formation of pyrophosphate on hydroxyapatite in the presence of water at ambient temperature. The yield of pyrophosphate based on thioester ranges from 2.5% to 11.4% and depends upon the pH and concentration of reactants. Reaction of 0.130 M hydroxyapatite suspended in a solution of 0.08 M sodium phosphate and 0.20 M imidazole hydrochloride (pH 7.0) with 0.10 M N,S-diacetylcysteamine for 6 days gives the highest yield of pyrophosphate (11.4%). Pyrophosphate formation requires the presence of hydroxyapatite, sodium phosphate and the thioester, N,S-diacetylcysteamine. The related thioester, N,S-diacetylcysteine, also yields pyrophosphate in reactions on hydroxyapatite.
Second human protein with homology to the Escherichia coli abasic endonuclease exonuclease III.

There are two major apurinic/apyrimidinic (AP) endonuclease/3′-diesterase families designated after the Escherichia coli proteins exonuclease III (ExoIII) and endonuclease IV (EndoIV). These repair proteins function to excise mutagenic and cytotoxic AP sites or 3′-phosphate/phosphoglycolate groups from DNA. In mammals, the predominant repair endonuclease is Ape1, a homolog of ExoIII, whereas a mammalian homolog to EndoIV has not been identified to date. We have identified a human protein termed Ape2 that represents a subclass of the ExoIII family (exhibiting highest similarity to the Saccharomyces cerevisiae ETH1/APN2 gene product) and maintains many of the essential functional residues of the ExoIII-like proteins. The human protein is 518 amino acids with a predicted molecular mass of 57.3 kDa and a pI of 8.65. Unlike Ape1, this protein exhibited only weak ability to complement the repair defects of AP endonuclease/3′-repair-defective bacteria and yeast. Similarly, a weak, but specific, DNA-binding and incision activity for abasic site-containing substrates was observed with partially purified Ape2 protein. APE2 is located on the X chromosome at position p11.21 and consists of six exons. The transcript for APE2 is ubiquitously expressed, suggesting an important function for the encoded protein. An Ape2 green fluorescent fusion protein localized predominantly to the nucleus of HeLa cells, indicating a nuclear function; this localization was dependent on the C-terminal domain. We discuss our results in the context of the evolutionary conservation of the AP endonuclease families and their divergent activities and biological contributions. Environ. Mol. Mutagen. Environ. Mol. Mutagen. 36:312–324, 2000. Published 2000 Wiley-Liss, Inc.
Capillary Electrophoresis Chips with Thick-Film Amperometric Detectors: Separation and Detection of Hydrazine Compounds

A miniaturized analytical system for separating and detecting toxic hydrazine compounds, based on the coupling of micromachined capillary electrophoresis (CE) chips with removable thick-film amperometric detectors is described. The study also represents the first example of using a chemically modified electrode for microchip CE applications. The microsystem with the electrocatalytic palladium-deposited detector offers a rapid (2 min) low-potential (+0.5 V vs. Ag/AgCl) simultaneous detection of hydrazine, methylhydrazine, dimethylhydrazine, and phenylhydrazine. Such compounds could be detected down to the 1.5×10–6 M level, with linearity over the 2×10–5 M–2×10–4 M range examined. While the concept of miniaturized separation/detection systems is presented within the framework of hydrazine compounds, such devices should be attractive for field monitoring of other classes of toxic contaminants. The design of the microsystem permits rapid replacement of the detector strip and a convenient surface modification (in a separate, optimal cell). The development of fast-responding miniaturized systems, with negligible waste production, holds particular promise for meeting the requirements of field ‘Green Analytical Chemistry’.
Evaluation of 64Cu- and 125I-radiolabeled bitistatin as potential agents for targeting αvβ3 integrins in tumor angiogenesis

The formation of new blood vessels (angiogenesis) is a feature common to all solid tumors. The integrin receptor alpha(V)beta(3), which is found on endothelial cells lining newly growing blood vessels at a higher density than on mature blood vessels, is being explored as a marker for tumor angiogenesis. Bitistatin, a member of the disintegrin family of polypeptides, has affinity for alpha(V)beta(3) integrins. To determine whether radiolabeled bitistatin could target tumors, its biodistribution was tested in tumor-bearing mice. For initial validation studies, (125)I-bitistatin was injected into BALB/c mice bearing EMT-6 mouse mammary carcinoma tumors, a model that is highly vascular but which lacks alpha(V)beta(3) directly on tumor cells. Tumor uptake reached maximal values (11.7 +/- 4.6 %ID/g) at 2 h. Co-injection of 200 microg of unlabeled bitistatin reduced tumor uptake 62%, suggesting that the binding of (125)I-bitistatin is receptor-mediated. This work was extended to include the beta(+)-emitting radionuclide (64)Cu, which was attached to bitistatin via 1,4,7,10-tetraazacyclododecane-N,N',N' ',N' "-tetraacetic acid (DOTA). This modification did not significantly alter receptor binding in vitro. MicroPET images obtained with (64)Cu-DOTA-bitistatin showed that the tumor could easily be identified 4 h after administering the radiopharmaceutical. The biodistribution of (64)Cu-DOTA-bitistatin differed from the (125)I analogue, in that maximum tumor uptake was nearly 8-fold lower and took at least 6 h to reach maximal binding (1.6 +/- 0.2 %ID/g). As with (125)I-labeled bitistatin, the (64)Cu conjugate showed a 50% reduction in tumor uptake with the co-injection of 200 microg of unlabeled bitistatin (0.8 +/- 0.2 %ID/g). Competition studies with integrin-specific peptides indicated that the tumor uptake was related to both alpha(v)beta(3) and alpha(IIb)beta(3) integrin binding. To see if tumor uptake could be improved upon, (64)Cu was tethered to bitistatin using bromoacetamidobenzyl-1,4,7,10-tetraazacyclododecane-N,N',N' ',N' "-tetraacetic acid (BAD). Tumor uptake for (64)Cu-BAD-2IT-bitistatin was higher than the DOTA conjugate at all time points, reaching a maximum at least 6 h postinjection (5.2 +/- 0.6 %ID/g); however, this was accompanied by higher uptake in nontarget organs at all time points. Radiolabeled ligands of this type may be useful in the targeting of tumor angiogenesis, but the choice of radiolabeling approach has a significant impact on the in vivo properties of the radioligand.