cssi/SciSciGPT-SciSciNet huggingface dataset:
To waffinity and beyond: a scalable architecture for incremental parallelization of file system code

In order to achieve higher I/O throughput and better overall system performance, it is necessary for commercial storage systems to fully exploit the increasing core counts on modern systems. At the same time, legacy systems with millions of lines of code cannot simply be rewritten for improved scalability. In this paper, we describe the evolution of the multiprocessor software architecture (MP model) employed by the Netapp® Data ONTAP® WAFL® file system as a case study in incrementally scaling a production storage system.The initial model is based on small-scale data partitioning, whereby user-file reads and writes to disjoint file regions are parallelized. This model is then extended with hierarchical data partitioning to manage concurrent accesses to important file system objects, thus benefiting additional workloads. Finally, we discuss a fine-grained lock-based MP model within the existing data-partitioned architecture to support workloads where data accesses do not map neatly to the predefined partitions. In these data partitioning and lock-based MP models, we have facilitated incremental advances in parallelism without a large-scale code rewrite, a major advantage in the multi-million line WAFL codebase. Our results show that we are able to increase CPU utilization by as much as 104% on a 20-core system, resulting in throughput gains of up to 130%. These results demonstrate the success of the proposed MP models in delivering scalable performance while balancing time-to-market requirements. The models presented can also inform scalable system redesign in other domains.
Resonant switched capacitor stacked topology enabling high DC-DC voltage conversion ratios and efficient wide range regulation

This paper presents a stacked-topology resonant switched-capacitor (ResSC) dc-dc converter to achieve a high voltage conversion ratio. The topology can be generalized to any N-to-1 dc-dc conversion application with only a single inductor. Multiphase interleaving can be further employed to improve the ripple cancellation and reduce requirement for bypass capacitors. To enable a wide output range while maintaining high efficiency, a phase shift operation is adopted. The regulation is maintained with frequency modulation. The controller is designed with the aid of current phase compensation in addition to voltage mode control. A prototype of a nominal 4-to-1 two phase interleaved resonant switched capacitor converter has been built and tested. The control and regulation of the output voltage are verified through the experiment. Burst mode is further introduced to improve efficiency at the light load condition.
Matrix Li-Yau-Hamilton estimates for the heat equation on Kähler manifolds

In [L-Y], Peter Li and S.-T. Yau developed the fundamental gradient estimate, which is now widely called the Li-Yau estimate, for any positive solution u(x, t) of the heat equation on a Riemannian manifold M(n = dimRM) and showed how the classical Harnack inequality can be derived from their gradient estimate. When M is complete and of nonnegative Ricci curvature, the Li-Yau estimate is sharp. Later in [H2], Richard Hamilton extended the Li-Yau estimate to the full matrix version of the Hessian estimate of u under the stronger assumptions that M is Ricci parallel and of nonnegative sectional curvature. In this paper, we consider positive solutions to the heat equation ( ∂
Mycophenolate Mofetil Withdrawal With Conversion to Everolimus to Treat BK Virus Infection in Kidney Transplant Recipients.

Abstract Background BK virus (BKV) is a significant post-transplant infection. Mammalian target of rapamycin inhibitors (mTORis) reduce BKV large T antigen expression in vitro and are associated with lower rates of BKV infection when used as de novo immunosuppression in clinical studies. Methods We performed a prospective, single-center, randomized, open label pilot trial to evaluate the impact of mycophenolate mofetil (MMF) withdrawal with conversion to the mTORi everolimus versus a 50% reduction of the MMF dose for the treatment of BKV infection after kidney transplantation. Patients maintained on tacrolimus, MMF, and corticosteroids that developed BK viremia or BK viruria ≥1 × 10 6 copies/mL were eligible. The primary endpoint was a >50% reduction of BK viruria or clearance of viremia at 3 months postrandomization. Results Forty patients were enrolled and randomized in a 1:1 manner; 11 (55%) and 8 patients (40%) reached the primary endpoint in the everolimus group and the MMF group, respectively ( P = .53). Of those with BK viremia at the time of enrollment, 8 of 16 (50%) and 5 of 15 (33.3%) cleared the viremia by month 3 in the everolimus conversion and MMF dose reduction groups, respectively ( P = .47). Conclusion Conversion from MMF to everolimus in BKV infection demonstrated a trend toward improved viral clearance but did not reach statistical significance.
Caribbean Communication: Social Mediation Through the Caribbean ICT Virtual Community (CIVIC)

New technologies, represented by information and communication technologies (ICTs), are changing the communication pattern taking place over the Internet throughout the Caribbean region. These ICTs have increased the way individuals connect and create new ways of direct virtual participation and communication. Virtual communities enabled by computer-mediated communication are an example of the type of technologies that enable interpersonal online communication. This chapter examines the Caribbean ICT Virtual Community known as “CIVIC” utilizing netnography as the method to study the cultural behavior of members of the collaborative virtual environment fostered by this online community.
Modeling and test generation for combinational hardware Trojans

Due to globalization of semiconductor manufacturing, appearance of malicious circuitry known as hardware Trojan is now a recognized security threat. A Trojan may be added to the verified netlist without the knowledge of the designer or user causing unexpected malfunction or data theft when the device is in use. In this research we devise tests that would detect a Trojan in a manufactured chip. We recognize that a Trojan must escape manufacturing tests provided with the netlist by the designer. Based on the two parts of a Trojan, namely, a trigger derived as a Boolean function of any set of signals and a payload (typically, an XOR gate) inserted on a signal line, we develop a test generation model. A single-line trigger combined with a single payload line gives a set of 2K × (K − 1) Trojans in this model for a circuit with K signal lines. Tests for these are shown to be vectors that detect “conditional stuck-at” faults, for which we give a test generation algorithm using standard ATPG tools. The model allows us to define and measure a Trojan coverage metric for tests. Results show scalability of these tests, besides being more effective in detecting real Trojans than N-detect stuck-at test vectors or random vectors.
Toward a biochemical classification of depressive disorders. III: Pretreatment urinary MHPG levels as predictors of response to treatment with maprotiline

Pretreatment urinary MHPG levels were examined in 28 depressed patients as a possible predictor of response to treatment with maprotiline, a tetracyclic antidepressant that exerts potent effects on norepinephrine uptake, but has little effect on serotonin uptake. Maprotiline was administered in doses up to 150 mg/day during the first 2 weeks after which time the dose could be increased incrementally up to 300 mg/day if indicated clinically. At 2 weeks, patients with low pretreatment urinary MHPG levels responded more favorably to treatment than did patients with high MHPG levels. At 4 weeks, patients with low MHPG levels continued to show more favorable responses; however, differences between the two groups were less clear-cut than at 2 weeks. The findings suggest that patients with low pretreatment urinary MHPG levels are more sensitive to, and respond more rapidly to, treatment with maprotiline than patients with high pretreatment urinary MHPG levels.
Fostering Security: Spiritually Informed Attachment-Based Therapy for Infants and Caregivers

The attachment relationship between an infant and primary caregiver is vital to the infant’s well-being. Attachment studies show that a caregiver’s ability to accurately reflect the infant’s feelings and intentions shapes the infant’s sense of security with others throughout life. However, these studies often neglect societal injustices and experiences of oppression that may also critically impact a child’s sense of security. In this chapter I will demonstrate how to integrate socially just, attachment-based interventions with spiritually based interventions. Theory and research indicate the possibility of influencing relationships with others by healing beliefs about God. Through a case example, I will demonstrate how to (1) strengthen a caregiver’s ability to reflect the infant’s experience by accessing caregiver beliefs about God and (2) validate experiences of injustice in order to better navigate oppressive systems. The goal is to foster security by increasing affect regulation, caregiver’s reflective stance, and an understanding of systemic oppression.
A Low Noise Figure 28GHz LNA in 22nm FDSOI Technology

This paper presents a 28GHz low noise amplifier (LNA) implemented in 22nm FDSOI technology. The LNA is based on inductively degenerated common source topology with cascode device. With several special layout techniques, the LNA achieved best in class noise figure (NF). At 28GHz, the LNA has a gain of 12dB, input referred third-order intercept point (IIP3) of 3.0dBm and input reference 1-dB compression point (IP1dB) of - 7.6dBm. The 1-dB and 3-dB bandwidth of the LNA is 8.5GHz and 15.1GHz, respectively. The lowest achieved NF is 1.46dB at 24GHz with power dissipation (PDC) of 9.8mW. Another LNA with larger device width was also implemented to achieve better NF. For this LNA, the lowest achieved NF is 1.35dB at 24GHz with PDC of 13.0mW. It could also achieve 1.8dB NF at 28GHz at 5.0mW PDC.
Restructuring a General College Chemistry Sequence Using the ACS Anchoring Concepts Content Map

Many STEM (science, technology, engineering, and mathematics) disciplines require a two-semester sequence of introductory college chemistry, which are thus critical gateway courses to a variety of majors. Recognizing the benefit to educators of a structure of content learning across the chemistry curriculum, in 2012, the American Chemical Society (ACS) developed the Anchoring Concepts Content Map, or ACCM. The development and subsequent revision of the general chemistry ACCM inspired the restructuring of our first-year chemistry sequence. Thus our CHEM 1001 and 1002 courses, taught in an atoms-first framework, were reorganized into a set of nine modules, each intentionally linked to one (or more) anchoring concept of the ACCM. In this initial effort, we have developed the course modules and subtopics and a set of learning objectives for each module and linked these to the general chemistry ACCM. To facilitate the initial teaching of the courses, the redesign occurred during the academic year, and the courses were taught in summer term 2019 using a flipped classroom design with three weekly 100 min face-to-face discussion meetings and two weekly laboratories for the 6 week long courses. Herein we describe the course design and its mapping onto the ACCM and discuss the results of the initial implementation, with suggestions given for future adaptations.
On the stability of projection-based model order reduction for convection-dominated laminar and turbulent flows

Abstract In the literature on nonlinear projection-based model order reduction for computational fluid dynamics problems, it is often claimed that due to modal truncation, a projection-based reduced-order model (PROM) does not resolve the dissipative regime of the turbulent energy cascade and therefore is numerically unstable. Efforts at addressing this claim have ranged from attempting to model the effects of the truncated modes to enriching the classical subspace of approximation in order to account for the truncated phenomena. The objective of this paper is to challenge this claim. Exploring the relationship between projection-based model order reduction and semi-discretization and using numerical evidence from three relevant flow problems, this paper argues in an orderly manner that the real culprit behind most if not all reported numerical instabilities of PROMs for turbulence and convection-dominated turbulent flow problems is the Galerkin framework that has been used for constructing the PROMs. The paper also shows that alternatively, a Petrov-Galerkin framework can be used to construct numerically stable and accurate PROMs for convection-dominated laminar as well as turbulent flow problems, without resorting to additional closure models or tailoring of the subspace of approximation. It also shows that such alternative PROMs deliver significant speed-up factors.
Planning with Partner Uncertainty Modeling for Efficient Information Revealing in Teamwork

Communication among team members is important for efficient teamwork, to coordinate behavior and ensure that all team members have the information they need to complete the task. To enable effective communication and thus efficient teamwork, we propose a multi-agent planning approach to revealing information based on its benefit to joint team performance. By explicitly modeling the partner’s knowledge and behavior, our approach allows a robot in a team to reason about when information is useful, how the communication is effective, and to communicate through efficient actions. That is, the robot provides only the necessary information for task completion, provides the information at the time that it is needed, and through the action(s) that optimizes team performance. We validated this approach in a human study in which participants walk together with a robot to a destination that is known only to the robot. We compared to a legible motion generation approach, and showed that users perceived our approach as more natural, socially appropriate, and fluent to team with, while being both more predictable and intent-clear. The ratings of our approach are equal or higher than legible motion across a1118 survey items.CCS CONCEPTS. Computing methodologies →Robotic planning; Multi-agent planning; • Human-centered computing →User studies. ACM Reference Format:Shih-Yun Lo, Elaine Schaertl Short, and Andrea L. Thomaz. 2020. Planning with Partner Uncertainty Modeling for Efficient Information Revealing in Teamwork. In Proceedings of the 2020 ACMlIEEE Intemational Conference on Human-Robot Interaction (HRI’20), March 23-26, 2020, Cambridge, United Kingdom. ACM, New York, NY, USA, 9 pages. https://doi.org/10.1145/3319502.3374827
Development and statistical database analysis of hardened concrete properties made with recycled concrete aggregates

Abstract The use of recycled concrete aggregates (RCA) as a replacement in new concrete has gained popularity worldwide as a method of reducing natural aggregate consumption. Many engineers, owners, and agencies are reticent to use RCA due to a lack of understanding on how the material will impact overall concrete properties. This lack of acceptance has been hindered by the difficulty of doing large-scale studies because of the time and cost of casting different concrete mixtures. Many individual studies have been completed but little work has been done to analyze that work to make broad conclusions on RCA concrete mechanical properties. This paper presents the development and analysis of a database of mechanical properties of concrete containing coarse RCA generated from 115 peer-reviewed journal articles. A sensitivity study of RCA systems was conducted through a full-factorial analysis to explore how the mixture design proportions influence the RCA concrete hardened properties. On average, the compressive strengths of concrete systems with 20% or less RCA replacement were 2% lower than that of the natural aggregate systems. Increased levels of RCA replacements decreased the average concrete compressive strengths with the highest average strength loss, in which a 10% reduction compared to natural aggregate systems is observed at 100% RCA replacement level. Results indicate that, in general, adequate concrete strengths for a variety of applications can be achieved at all replacement ratios of coarse RCA. Impacts of mixture design properties on particular mechanical properties are presented along with bivariate contour plots that can be used by concrete mixture designers to better estimate RCA concrete properties. This work supports an increased adoption of RCA by providing broad conclusions supported by statistical analysis that show typical performance of RCA concrete across a variety of design inputs.
Nocardia farcinica Brain Abscess in an Immunocompetent Host With Pulmonary Alveolar Proteinosis: A Case Report and Review of the Literature.

A 55-year-old immunocompetent male presented with new-onset seizures and acute respiratory failure requiring intubation and a stay in the medical intensive care unit. Magnetic Resonance Imaging (MRI) of the brain revealed ring-enhancing lesions, and Computed Tomography (CT) chest showed ground-glass opacity. The patient underwent craniotomy and bronchoscopy, followed by culture of the purulent aspirate from lesions in the brain and bronchoalveolar lavage (BAL). After extensive infectious workup, the patient was diagnosed with a Nocardia farcinica brain abscess plus underlying pulmonary alveolar proteinosis (PAP). Based on a recommendation from an infectious disease expert, the patient was treated with trimethoprim-sulfamethoxazole (TMP/SMX). This case highlights the importance of understanding that, though rare, infections such as nocardiosis can present in immunocompetent patients and cause severe morbidity.
Review of key vertical-cavity laser and modulator advances enabled by advanced MBE technology

In this special issue honoring Professor Arthur Gossard, I am delighted to be able to review a small segment of the work he has enabled while at UCSB on the subject of the title, but further limited to devices grown all-epitaxially. When he arrived in 1987 from Bell Labs, he had already been consulting on the installation of our new Gen-II MBE that we intended to use for vertical-cavity Fabry–Perot modulators, devices somewhat similar to those he had grown at Bell Labs. However, within a couple of years, we obtained leading results on reflection modulators, moving the on/off contrast from prior values of less than 5:1 to more than 50:1 with insertion losses of less than 2 dB, required voltages in the 2–4 V range, and changes in reflection per volt to ∼20%/V. These had multiple-quantum-well (MQW) active regions to phase shift and partially absorb the resonant lightwaves within a cavity formed between two distributed-Bragg-reflector (DBR) mirrors all formed in the AlGaAs/GaAs system. Also in this same period, novel vertical-cavity surface-emitting laser (VCSEL) structures analogous to the modulators were developed. They had strained InGaAs/GaAs MQW actives and AlGaAs/GaAs DBRs and operated near 980 nm. The initial new idea was to place active quantum wells only at the maxima of the cavity E-field standing wave, which provides nearly a doubling of the modal gain they contribute. These designs quickly led to leading results in threshold current ( 1 mW—1991), power out (up to 113 mW cw—1993), and temperature stability with gain offset (constant output over 50 °C—1993). Additional notable results in the 1990s included a selective oxidation of AlGaAs to form lens-like intra-cavity apertures for dramatic reductions in optical cavity loss; the first strained layer InGaAlAs/GaAs 850 nm VCSELs; and an 8-wavelength division multiplexing VCSEL array integrated within a 60 μm diameter for direct emission into a multimode fiber. In the 2000s, results included all-epitaxially grown 1310 nm and 1550 nm VCSELs that employed AlGaAsSb DBRs and AlGaInAs actives with tunnel junctions to enable two n-type contacts on InP for low thermal and electrical resistance; multi-terminal VCSELs for polarization modulation to double the information output on a single optical beam; and a novel high-speed, high-efficiency design that incorporated sophisticated bandgap engineering in the DBRs and carbon doping for low optical loss and electrical resistance, midlevel Al-content mirror layers near the cavity for deep oxidation to reduce capacitance, and a redesigned lens-like aperture for reduced mode volume. This latter design gave record modulation bandwidth and efficiency results then, and it is still being used around the world for the leading results today. In the most recent decade, InGaAsSb/AlGaAsSb/GaSb materials for VCSELs and photonic ICs have been studied for emission in the 2–4 μm wavelength range.
Resolution of Abdominal Pain After Coil Embolization of Varicocele with Robotic Resection of Gonadal Vein.

Background: Chronic pain in the region of varicocele embolization is not well described and can be a challenging symptom to manage, with limited options for treatment after failing conservative measures. It is important to counsel patients of this potential complication when determining the best option for varicocele repair. To our knowledge, there are no reported cases of gonadal vein excision for chronic abdominal pain after coil embolization. Case Presentation: A 63-year-old Caucasian male presented to our urology clinic after coil embolization. His testicular pain resolved but he reported new left-sided abdominal pain after coil embolization for a large left varicocele. After failing conservative measures including nonsteroidal anti-inflammatory drugs, antibiotics, and prednisone, he was referred for further work-up and to discuss treatment options. On presentation, the patient reported pain on the left side of his abdomen consistent with the location of gonadal vein. After extensive counseling that surgical removal may not alleviate his pain, robotic gonadal vein excision was offered, and the patient elected to proceed. Intraoperatively, the coils were easily seen through the wall of the vessel. This segment of the gonadal vein containing the coil was excised in its entirety. The patient was discharged on postoperative day 1 with only nonsteroidal pain medications. Six weeks postoperatively, the patient reported no complications, and almost complete resolution of his preoperative pain. Conclusions: To our knowledge, this is the first case report demonstrating the surgical removal of the gonadal vein for treatment of chronic abdominal pain after varicocele embolization. After failing conservative measures, this may present another viable treatment option to address this difficult complication in a select group of patients.
Against Using the Book Proposal to Rethink Your Book: Why and How to Work on Your Book Instead

Drawing from personal experience revising my dissertation into a book and helping dozens of authors do the same, I put language to a critical yet challenging phase in this process: working on one’s...
P1 Evaluating Food Waste Knowledge, Attitudes and Behaviors in College Students at a Midwestern University

Background An estimated 40% of food produced in the United States is wasted, and approximately 90 billion pounds are discarded by consumers annually. Food waste threatens the environment and contributes to food insecurity. Identifying methods to reduce personal food waste represents a potential strategy to actively engage in behaviors that positively impact the food system and environment. Objective Explore current knowledge, attitudes, and behaviors related to food waste in college students. Results will provide details to assist in developing interventions to mitigate consumer food waste. Study Design, Setting, Participants A survey was released to 30,773 undergraduate and graduate students enrolled in a midwestern university. Questions addressed knowledge and attitudes associated with food waste, concern for environmental consequences, transtheoretical model stage, and application of mitigation behaviors. Measurable Outcome/Analysis A response rate of 6.3% provided a total of 1,931 responses for analysis. Recruitment was done via email, and data were collected via Qualtrics. A descriptive analysis was conducted to identify initial characteristics of this population. Results Evaluating the stage of change for reducing personal food waste showed 8% of respondents in precontemplation, 30% in contemplation, 4% in preparation, 57% in action and maintenance, and 1% in relapse. However, on a 5-point Likert scale from not at all knowledgeable (1) to very knowledgeable (5), 64% designated they were only slightly (2) or somewhat knowledgeable (3) about ways to reduce food waste. Conclusion Evidence suggests that this audience is open to change, yet do not have sufficient knowledge regarding ways to reduce food waste. Thus, guidance may be warranted to help them acquire the information and skills to be successful. Understanding these barriers and attitudes will allow for the development of specific, tailored approaches to waste reduction that acknowledge where students are and carve a path toward a more sustainable food behavior.
Legal Ethics and Federal Taxes, 1945-1965: Patriotism, Duties and Advice

Legal Ethics and Federal Taxes, 1945-1965: Patriotism, Duties and Advice provides a timely historical review of legal ethics and federal taxes. Focusing on the first two decades of the modern income tax (1945-1965), the Article reviews the ethics literature of the tax bar, which was mostly written by very prominent tax lawyers (a founder of Paul, Weiss; partners at Sullivan & Cromwell, Willkie Farr, etc.), tax professors (including the dean at Harvard Law School), and government officials (including key advisors to FDR, JFK, and LBJ). This seemingly forgotten literature provides a remarkable contrast to today’s anti-tax climate, especially given that the highest marginal individual tax rate during 1945-1965 was 94%. The writers of this period emphasized the patriotic duty to support the federal government by paying taxes, describing taxes, for example, as the price to maintain capitalism (Merle Miller) and a “blessing” (Erwin Griswold). Several stressed the ethical duty of lawyers to improve their clients’ respect for the tax system (Norris Darrell, e.g.). “Ethics” for these writers was not an issue of the ABA canons but rather a more general, philosophical reflection. For example, in 1949, the tax committee of the ABA issued a report on the importance of natural law jurisprudence in tax. In 1952, the discussion at the Tax Law Review banquet (which was nominally dedicated to discussing “Ethical Problems of Tax Practitioners”) developed into a debate over whether or not Americans were more degenerate then than in the past (Edmond Cahn) or merely more self-conscious (Thomas Tarleau). But the ethics writers were also concerned with specific issues that endure to this day, such as when to disclose an arguable but uncertain tax position – some (Randolph Paul, e.g.) arguing almost any position the government was likely to question should be disclosed, others (Boris Bittker, e.g.) arguing against disclosure so long as the position was reasonable. There was wide disagreement as to whether or not tax lawyers owed a special duty to the system, but wide agreement that this theoretical debate was nearly moot given that conservative tax advice was usually not only the most ethical but the most practical. This pragmatic attitude – emphasizing that good tax practice, good tax ethics, and good tax advice tended to converge – reflected the “real world” orientation of these professionally accomplished writers, even though, by today’s standards, many of their statements seem idealistic. The salvaging of this forgotten literature is timely not only in its relevance to contemporary debates, but also its relevance to the increasing historical research of the income tax as its 100th anniversary approaches.
Downstream instabilities of Ar/SF/sub 6/ inductive plasma discharges

Summary form only given, as follows. A new class of relaxation oscillations is observed in low-frequency inductive plasma discharges operated with low-pressure argon and SF/sub 6/ gas mixtures The oscillations occur in a certain domain of gas pressure, radio frequency power, electronegative gas chemistry, and downstream region length Langmuir probes and fast video imaging show that density perturbations grow in tens of microseconds in a quasi-spherical downstream layer. Large density variations are then seen below the layer until the initial plasma profile is recovered. The data suggest that some plasma instability develops periodically in the downstream layer. Linear fluid and kinetic calculations predict ion two-stream instabilities when the positive and negative ions develop sufficiently large drift velocities of opposite sign in the downstream region. The thresholds and the growth rates of the instabilities are calculated and are found in fair agreement with the observations. The instability models can explain several key experimental features.
Low threshold, highly efficient phase conjugation using optical coherent transients

We discuss and demonstrate two approaches to achieving low threshold, highly efficient phase conjugation using optical coherent transients in rare-earth ion doped crystals. One approach utilizes coherent media inversion and the other utilizes integration gain.
Temperature dependent visible photolumineseence of Eu-doped GaN on Silicon

A spectroscopic study of Eu-doped GaN grown on silicon by solid state molecular beam epitaxy is presented. The temperature dependence of the continuous-wave and time-resolved luminescence properties reveals details about the energy transfer rates and thermal activation energies.
A non-standard proof of the Briançon-Skoda theorem

Using a tight closure argument in characteristic p and then lifting the argument to characteristic zero with the aid of ultraproducts, I present an elementary proof of the Briancon-Skoda Theorem: for an m-generated ideal a of C[[X 1 ,...,X n ]], the m-th power of its integral closure is contained in a. It is well-known that as a corollary, one gets a solution to the following classical problem. Let f be a convergent power series in n variables over C which vanishes at the origin. Then f lies in the ideal generated by the partial derivatives of f.
Calcification of fetal teeth as an index of fetal maturation.

Abstract Abdominal x-rays (by the technique of Bishop 2 ) were taken of 70 gravid women, and fetal age was assessed by the degree of calcification of the fetal teeth. In 7 cases, the teeth could be visualized, and an accurate estimate of gestational age was made from the radiograph. However, it appears at present that visualization of the fetal teeth can be achieved only when the fetal head is not in the maternal pelvis.
Beyond inversionless gain to a demonstration of field-enhanced lasing

Summary form only given. We experimentally demonstrate field-enhanced lasing, i.e., lasing made possible through an excitation-field-mediated boost in the gain normally realizable on a weakly inverted transition. The excitation field responsible for the boost in gain, the "helper" field couples the lasing transition to another transition in a cascade-type three-level atomic system. The gain boosting operative in our driven three-level-atom experiments derives from the same essential physics that gives rise to the "inversionless" gain that has recently attracted so much attention. In terms of achieving laser operation in new regimes, gain boosting may play much the same role as inversionless gain.
Inside the Coasean Firm: Competence as a Random Variable

The work of Ronald Coase is notable for two primary reasons. First, it introduced the notion of transaction costs to explain the formation and maintenance of firms, Second, it advanced our understanding of the critical topic of social costs. Yet, while transaction costs are key to understanding why firms are organized, they do not offer a complete explanation of how they are organized. A richer account of the problem properly stresses that differences in individual levels of competence, as well as individual variations in temperament and taste, explain why, for example, some firms are organized as partnerships and others as straight employment arrangements, with many permutations in between. Understanding differential levels of competence also helps to explain issues in areas from employment discrimination law to capital markets and tort liability.
RHO AND RIBOSOME MUTATION INTERACTION: LETHALITY OF rho-15 IN rpsL or rpsE STRAINS, AND rho-15 METHIONINE AUXOTROPHY IN rps+ STRAINS OF ESCHERICHIA COLI

The phenotype of Escherichia coli K-12 carrying rho-15 in the genetic background DW319 ilv lacZ::IS1 is described. Seventy-eight percent (70/90) of Ilv+ transductants acquired the following phenotype: temperature-sensitive growth on minimal salts medium, Ts+ growth on complex medium and suppression of the lac polar mutation. At 42 degrees on minimal medium, the rho-15 transductants were cross-fed by a substance diffusing from Rho+ transductants or controls. The requirement for this substance was satisfied by methionine or cystathionine, but not by any other single amino acid or combination of amino acids, by spermidine, or by mono- or divalent cationic salts.--Transduction of rho-15 into four other Ilv- recipients revealed two phenotypic patterns. Recipients with rpsL or rpsE ribosomes yielded rho-15 transductants that were Ts on all media, or Ts on minimal medium whether or not methionine was present. The effect of the ribosome on expression of rho-15 was confirmed by transduction of appropriate rps alleles into DW319, followed by co-transduction of rho-15 with Ilv+. The growth rate of double rho-15 rpsL or rho-15 rpsE strains was severely reduced at 42 degrees in comparison with strains carrying any of these single mutations. Models for rho and ribosome interaction are presented.
Wide Range Displacement Expressions for Standard Fracture Mechanics Specimens

Wide-range algebraic expressions for the displacement of cracked fracture mechanics specimens are developed. For each specimen two equations are given: one for the displacement as a function of crack length, the other for crack length as a function of displacement. All the specimens that appear in ASTM Test for Plane-Strain Fracture Toughness of Metallic Materials (E 399) are represented in addition to the crack mouth displacement for a pure bending specimen. For the compact tension sample and the disk-shaped compact tension sample, the displacement at the crack mouth and at the load line are both considered. Only the crack mouth displacements for the arc-shaped tension samples are presented. The agreement between the displacements or crack lengths predicted by the various equations and the corresponding numerical data from which they were developed are nominally about 3 percent or better. These expressions should be useful in all types of fracture testing including fracture toughness, K-resistance, and fatigue crack growth.
Inverse design and demonstration of a compact and broadband on-chip wavelength demultiplexer

An on-chip integrated wavelength demultiplexer designed using an inverse computational algorithm is experimentally demonstrated. 1,300 and 1,550 nm wavelength light is sorted in a device area of just 2.8 × 2.8 μm2.
Parallel-kinematic-mechanism-based monolithic XY micropositioning stage with rotary comb drive actuators

Micro-positioning stages fabricated using Micro Electro Mechanical Systems (MEMS) based processes have been critical in enabling micro/nano manipulation and probing. These stages have been extensively used in micro-force sensors, scanning probe microscopy and micro optical lens scanners. This paper presents the design, kinematic and dynamic analysis, fabrication and characterization of a novel monolithic micro-positioning XY stage. The design of the proposed micro-positioning stage is based on a Parallel Kinematic Mechanism (PKM). The PKM based design decouples the motion in the XY direction. Additionally, it restricts the parasitic rotation of the end-effector (table) of the micro-positioning stage while providing an increased motion range. The motion of the stage is linear in the operating range thus simplifying its kinematics. The truss like parallel kinematic mechanism design of the stage structure reduces its mass while keeping the stage stiffness high. This leads to a high natural frequency of the micro-positioning stage (1250Hz) and a high Q-factor of 156. The stage mechanism is fabricated on a Silicon-On-Insulator (SOI) substrate and is actuated by integrated electrostatic rotary comb drives. The fabrication process uses multi-layer patterning along with an Inductively Coupled Plasma Deep Reactive Ion Etching (ICP-DRIE). The use of ICP-DRIE enables the high aspect ratio etching that is required for the stage fabrication and its optimal actuation using the integrated electrostatic rotary comb drives. The fabricated stages have a motion range of more than 30 microns of decoupled displacements along the X and Y directions at a driving voltage of 200V.
Terahertz Pioneers: Manfred Winnewisser and Brenda Pruden Winnewisser: "Equating Hamiltonians to nature"

A brief biography of Manfred Winnewisser and Brenda Pruden Winnewisser is given highlighting their careers and professional achievements.
Sources of the New Deal Realignment: the Contributions of Conversion and Mobilization To Partisan Change

T _HE SOURCES of partisan realignments have been the subject of considerable research. How do realignments occur? More specifically, who in the electorate is realigned? Two competing hypotheses have been offered in answer to this question the mobilization hypothesis and the conversion hypothesis. The mobilization hypothesis claims that the shift in the relative strengths of the parties is a result of new voters entering the electorate. People are mobilized to participate who had been too young to vote, were ineligible to vote (e.g., women prior to the Nineteenth Amendment, immigrants prior to gaining their citizenship), or were convinced that previous electoral choices were irrelevant. These new voters, the mobilization hypothesis contends, contribute more to the electoral gains of the new majority party than do the established, pre-realignment cohort of voters. Evidence supporting the mobilization hypothesis in the New Deal realignment has been found by Key (1955), Campbell et al. (1960), Sellers (1965), Converse (1976), Petrocik (1981), and Wanat (1979). The most thorough and extensive work in support of the mobilization hypothesis has been conducted by Andersen (1979a and 1979b). Although Andersen's analysis drew upon a variety of data, the core of her analysis rested on SRC party identification recall data collected from 1952 to 1972. These data were used to demonstrate that voters entering the electorate in the realignment era were overwhelmingly Democratic. Erikson and Tedin (1981) dispute Andersen's findings. They note that the partisanship recall question used by Andersen has proven to be highly unreliable (Niemi, Katz, and Newman 1980; and Reiter 1980). This problem is apparent in the distribution and trends of party identification constructed from the recall measure. According to these data, the Democrats had a plurality of the electorate as early as 1920; they gained just 3 percent of the electorate from 1924 to 1930 (Andersen 1979a: 61); and they held nearly a two-to-one advantage over the Republicans among young voters in 1924 prior to the realignment. Such counterintuitive findings raise serious doubts about the reconstructed partisanship variable. Moreover, despite her earlier arguments asserting the validity of the measure, Andersen seems to acknowledge a problem when she admits that many young Democrats of the 1920s, identified as such by the recall measure, would have identified themselves at the time as independents or without a party (Andersen 1979: 67).1 Erikson and Tedin (1981: 952) also argue that
Analysis of singular stress fields at junctions of multiple dissimilar materials under mechanical and thermal loading

Abstract Traditional finite element analyses of the stress state in regions with dissimilar materials are incapable of correctly resolving the stress state because of the unbounded nature of the stresses. A finite element technique utilizing a coupled global (special) element with traditional elements is presented. The global element includes the singular behavior at the junction of dissimilar materials with or without traction-free surfaces. A hybrid global (special) element is developed utilizing the exact solution for the stress and displacement fields based on the eigenfunction expansion method under mechanical and thermal loading. The global element for arbitrary geometrical and material configurations, not limited to a few dissimilar material sectors, is interfaced with traditional local (conventional) elements while satisfying the inter-element continuity. The coupling between the hybrid global element and conventional finite elements is implemented into ansys , a commercially available finite element program. Also, the global element is integrated into the ansys graphical user interface for pre- and post-processing.
Fate of Candida albicans in neonatally thymectomized rats.

SummaryThe clearance of C. albicans organisms from the blood in Lewis rats is not altered in neonatally thymectomized rats despite the presence of profound immunological disturbances. The selective clearance of C. albicans by the lung is also unimpaired in these rats.
Neuropathic pain in diabetes—evidence for a central mechanism

Hyperexcitability of and aberrant spontaneous impulse generation by damaged first-order sensory neurons and their peripheral axons are well-established processes that strongly contribute to pain associated with diabetic neuropathy. Studies in the past 5 years, however, suggest that, as in many neuropathic pain disorders, central neuropathic mechanisms can also contribute to pain experienced with diabetes. These studies have demonstrated that thalamic dysfunction occurs in patients with diabetes mellitus, and that in experimental models of this disease neurons in the ventral posterolateral thalamus can become hyperexcitable, firing at abnormally high frequencies and generating aberrant spontaneous activity. In this article, we discuss these findings, which suggest that thalamic neurons can act as central generators or amplifiers of pain in diabetes.
Physicochemical studies of dinitrophenylated bovine serum albumin

The structural changes of bovine serum albumin (BSA) as a function of dinitrophenylation have been studied by disc gel electrophoresis, sedimentation velocity analyses, and circular dichroism. These experiments were designed to understand the molecular bases for the change in immunogenicity and antigenicity of BSA upon dinitrophenylation. Dinitrophenylated BSA tends to aggregate to dimers and higher aggregates. A concomitant large change in electrophoretic mobility was also observed. Circular dichroism studies reveal a large decrease in the alpha-helical structure of the BSA molecule.
Flexible and low-voltage integrated circuits constructed from high-performance nanocrystal transistors

Colloidal semiconductor nanocrystals are emerging as a new class of solution-processable materials for low-cost, flexible, thin-film electronics. Although these colloidal inks have been shown to form single, thin-film field-effect transistors with impressive characteristics, the use of multiple high-performance nanocrystal field-effect transistors in large-area integrated circuits has not been shown. This is needed to understand and demonstrate the applicability of these discrete nanocrystal field-effect transistors for advanced electronic technologies. Here we report solution-deposited nanocrystal integrated circuits, showing nanocrystal integrated circuit inverters, amplifiers and ring oscillators, constructed from high-performance, low-voltage, low-hysteresis CdSe nanocrystal field-effect transistors with electron mobilities of up to 22 cm(2) V(-1) s(-1), current modulation >10(6) and subthreshold swing of 0.28 V dec(-1). We fabricated the nanocrystal field-effect transistors and nanocrystal integrated circuits from colloidal inks on flexible plastic substrates and scaled the devices to operate at low voltages. We demonstrate that colloidal nanocrystal field-effect transistors can be used as building blocks to construct complex integrated circuits, promising a viable material for low-cost, flexible, large-area electronics.
Flexibility of Ordered Surface Hydroxyls Influences the Adsorption of Molecules in Single-Walled Aluminosilicate Nanotubes

Single-walled aluminosilicate nanotubes (NTs) are attractive for molecular separation applications because of their highly ordered structure, tunable dimensions, as well as their hydrophilic and functionalizable interiors. These NTs possess a pore surface consisting of an ordered array of silanol groups with flexible hydroxyls. We show that the flexibility of these hydroxyl groups is critical in the adsorption of hydrogen-bonding molecules. Specifically, we study the adsorption of water, methanol, CO2, and CH4 in the NT via grand canonical Monte Carlo (GCMC) simulations. The experimentally observed hydrophilicity of the surface can be captured in adsorption calculations only if the structural and orientational flexibility of the surface hydroxyls is incorporated. The adsorption selectivity of water over methanol is predicted to be larger than 100, which makes aluminosilicate NTs promising for dehydration of alcohols. Flexibility effects are less significant for the adsorption of non-hydrogen-bonding molec...
Scaling Laws for Fracture of Heterogeneous Materials and Rock.

Using computer simulation we show that, near the global failure point, the cumulative elastic energy released during fracturing of heterogeneous solids follows a power law with log-periodic corrections to the leading term. This is consistent with a recently proposed scaling law that relates the dynamics of the precursors of large earthquakes to their occurrence time, thus providing a rational basis for it in terms of rupture of the rock. It is also consistent with the scaling of acoustic emissions that precede fracture of composite materials, with the time to failure, and may thus provide a basis for predicting fracture of materials.
Use of serology in reptile medicine

Serologic assays are emerging as powerful tools for both diagnosing and screening collections of reptiles for exposure to and infection with certain pathogens. For the most part, these tests were developed in research laboratories with a specific interest in diseases of captive and free-ranging reptiles. Relatively few are commercially available, with most offered through individual research laboratories or universities. Tests have been developed for exposure to paramyxovirus of snakes, mycoplasma of tortoises and crocodilians, her-pesvirus infection of marine turtles and tortoises, cryptosporidium of snakes, and spirorchid trematodes of sea turtles. Of the various serologic tests, enzyme-linked immunosorbent assay (ELISA) is becoming the test with the most application. Although ELISA is relatively simple and has certain positive attributes such as high sensitivity and specificity, in the indirect format it does require specific anti-reptile immunoglobulins that recognize and bind to the antibody being assayed. In this report, we review reptile humoral immunity for the major orders of reptiles, assays available for determining exposure of reptiles to specific pathogens, and factors affecting the immune response of reptiles.
THE CULTURE OF WHOLE ORGANS : I. TECHNIQUE OF THE CULTURE OF THE THYROID GLAND.

1. A technique has been developed for the transplantation of the whole thyroid into the Lindbergh pump, and its perfusion, without the occurrence of infection, emboli, and other complications. 2. The gland remains alive during the period of perfusion, which lasted from 3 to 21 days. 3. The technique is simple enough to be used as a routine procedure for physiological or pathological studies of the thyroid gland.