cssi/SciSciGPT-SciSciNet huggingface dataset:
A central limit theorem for functionals of the Kaplan—Meier estimator

Abstract A central limit theorem is given for functionals of the Kaplan—Meier estimator when the censoring distributions are possibly different or discontinuous. In the i.i.d. case only one easily interpretable and simple integrability condition is needed. This condition reduces to the usual condition for the Lindeberg—Levy theorem when there is no censoring; it is also necessary in certain other situations. The weak convergence of the corresponding processes is also established. The simple proofs and conditions result from the martingale method of Gill (1983), an extension of an identity of Shorack and Wellner (1986) and a delicate treatment of the remainder terms.
The effects of ethanol on the development of gastric ulceration in the rat

Abstract The purpose of the study was to determine the effects of alcohol on stomach ulceration in 90 day old Sprague-Dawley albino rats over ten days of approach-avoidance stress. Sixty Ss were divided into four groups: a 10% alcohol and dextrose group, a 20% alcohol group, a dextrose control group, and a deprivation group which did not experience the approach-avoidance conflict. One-third of these groups was sacrified at 4, 8, and 10 days. When sacrified, the Ss stomachs were removed, mounted, photographed and rated by pathologiest using a four point scale. The results suggest that stress due to dietary disturbance was a greater factor in ulcer production that was the approach-avoidance conflict or the alcohol treatments. The administration of the alcohol solutions did not either increase the production of ulcers or interfere with healing. Further, the percentage of weight did not correlate with severity of ulceration. A pattern of ulceration develop in all groups. Ulceration increased from 0 to 4 days, continued this increase through 8 days, and then diminished to the 4 day severity level at 10 days which indicates: adaption to deprivation stress; healing of ulceration during stress; and healing of ulceration while under the influence of alcohol.
The asymptotic response of three-dimensional basin offsets to magnetotelluric fields at long periods; the effects of current channeling

A simple, inexpensive numerical algorithm is used to analyze the asymptotic long-period behavior of magnetotelluric (MT) fields in the vicinity of lateral offsets in sedimentary basins. The model is based on the distortion or channeling of telluric currents in a horizontal thin sheet. Although a gross oversimplification of nature, the model represents a class of structures which, because of excessive computer costs, have been relatively unstudied previously. Within, and closely adjacent to, the region of the three-dimensional (3-D) offset, significant distortion of the MT parameters occurs. Skewness coefficients vary from negligible values to over 0.7. Principal resistivities vary by an order of magnitude. On the other hand, there is not a clear correlation between the degree of distortion of the parameters usually evaluated during MT surveys and the magnitude of conventional 3-D indicators (e.g., the skewness coefficient). Calculations have simulated the technique of averaging resistivity parameters from a large number of field sites in order to arrive at a regionally representative one-dimensional (1-D) model. The results indicate that unless care is taken in adapting the nature of the averaging algorithm to the class of distortions encountered, significant bias of the averaged parameters may result. These results also suggest that formore » this class of structures grave problems may be associated with using the principal resistivity perpendicular to geologic strike, the so-called transverse magnetic (TM) mode, to infer an equivalent two-dimensional (2-D) model for the region. A 2-D model would likely show significant modulations in the physical character of the basement which are, in fact, an artifact of telluric distortion caused by current channeling in the surficial heterogeneity. 10 figures, 4 tables.« less
Infrared coagulator: a useful tool for treating anal squamous intraepithelial lesions.

The incidence of invasive anal squamous carcinoma in men who have sex with men is rising, particularly in those with human immunodeficiency virus. As in the cervix the high-grade squamous intraepithelial lesion is thought to be an invasive squamous cell carcinoma precursor. Cervical high-grade squamous intraepithelial lesions are treated by removing the squamocolumnar transition zone. This is not possible in the anus, where treatment is often surgical and is accompanied by significant pain and morbidity. Better office-based techniques to treat anal high-grade squamous intraepithelial lesions are needed. We employed the infrared coagulator™ in an office setting to ablate high-grade squamous intraepithelial lesions. A retrospective review of medical records was performed on 68 human immunodeficiency virus-positive men who have sex with men who underwent infrared coagulator™ ablation of biopsy-proven high-grade dysplasia from the time we began using the procedure in 1999. All patients have had at least six months of follow-up. Procedures were performed with local anesthesia on patients with discrete high-grade squamous intraepithelial lesions. Follow-up consisted of anal cytology with high-resolution anoscopy and biopsy of suspicious areas every three to six months. New or recurrent high-grade dysplasia was retreated. Patients with circumferential or bulky disease were treated in the operating room and were excluded from the study. Altogether, 68 patients met the enrollment criteria. The median patient age was 41 years (range 29–62 years). A total of 165 lesions were treated (mean 1.6 lesions, range 1–5) and only 46 (28 percent) persisted. However, 44 patients (65 percent) developed a new or persistent high-grade squamous intraepithelial lesion within a median time of 217 days (range 27–566 days) after infrared coagulation. The remaining 24 patients (35 percent) were free of high-grade dysplasia for a median of 413 days (range 162–1313 days) after infrared coagulation. When patients were treated a second or third time, the incidence of new or persistent high-grade dysplasia dropped to 58 percent and 40 percent, respectively. The probability of curing a retreated lesion was 72 percent. Using generalized estimating equations, the incidence of high-grade dysplasia decreased with repeated infrared coagulator™ treatments. No patient developed squamous-cell carcinoma, had a serious adverse event, or developed anal stenosis. The infrared coagulator™ is a safe, office-based modality for treating anal high-grade squamous intraepithelial lesion in human immunodeficiency virus-positive men who have sex with men. Successive treatments led to decreased recurrence rates.
Macromolecular Crowder and Ligand Compete for the Closed Domain Cleft of Maltose Binding Protein

Protein-ligand binding is central to many biochemical processes including enzyme catalysis/inhibition and cellular signaling. In the cellular context, these processes occur in milieus crowded with bystander macromolecules. Growing evidence suggests that the macromolecular crowders are not inert but influence the biochemical processes. A previous study of our lab demonstrated that a synthetic polymer crowder, Ficoll70, and a ligand, maltose, compete for binding with the maltose binding protein (MBP), a periplasmic protein involved in nutrient uptake and chemotaxis [Miklos and Zhou, PLoS ONE 8, e74969 (2013)]. Fluorescence and NMR spectroscopy showed that Ficoll70 weakly binds to MBP and this binding is abrogated by saturating amounts of maltose. MBP has a bi-lobed structure; the lobes close up upon ligand binding into the domain cleft. Competitive inhibition by Ficoll70 could result from the crowder preferentially binding either to the open cleft, thus rendering the protein incompetent for maltose binding, or to the closed cleft, thus blocking maltose from the binding site. To distinguish between these two possibilities, here we introduced MBP hinge mutations that result in cleft closure and enhancement of maltose binding affinity. With the closure mutants, MBP-Ficoll70 interactions would be expected to weaken in the open-cleft binding scenario but to be unperturbed or even strengthened in the closed-cleft binding scenario. Our data indicate a modest increase in Ficoll70 binding affinity for a closure mutant, thus supporting the closed-cleft binding scenario. A panel of mutants with varying degrees of cleft closure is being studied to validate the observation. Our study will provide new insight into the nonrandom nature of weak protein-crowder interactions in cellular environments.
Alteration of Medical Records Submitted for Medicolegal Review

THE PRACTICE of altering medical records out of fear of litigation may be an increasing problem. This topic has received no recent attention in the medical literature. Physicians' alterations of research data 1,2 and attitudes toward changing records to improve insurance collection 3,4 have been reported, but no documented cases in the medical literature describe altering the records of patients who sue physicians. This review describes the medicolegal aspects of four cases involving altered patient records. The discussion following the cases focuses on some practical considerations about making additions and changes to medical records. I have practiced medicine in academic centers for 20 years. Because of my academic orientation, several state medical boards, hospitals, malpractice insurance companies, physician groups, and even a few plaintiffs attorneys have sought my opinion on cases involving pending or potential litigation. In the last 5 years, there has been a disturbing increase in the proportion
Surface imaging by scanning tunneling microscopy

Abstract We discuss the potential of a new technique for surface imaging on an atomic scale: scanning tunneling microscopy. Examples for 3D topographies of surfaces and work-function profiles are given.
Classifying delinquent customers for credit collections: an application of probabilistic inductive learning

Abstract Probabilistic Inductive Learning (PrIL), a methodology that incorporates statistically determined measures of goodness with tree inductive algorithms from machine learning, has been applied to the credit collection operations of a major bank. Rules were induced from past customer account data to predict whether an account that is one month delinquent will be rectified or remain delinquent. Each of the rules has a reliability greater than that prescribed by management. The induced rules outperformed current scoring methods in predicting customer behavior on a holdout dataset. In addition, using the rules will result in matching current performance with 30% fewer contacts with delinquent customers.
The geometric phase in two-level atomic systems

Abstract We report the observation of the geometric phase in a closed two-level atomic system using stimulated photon echoes. The two-level system studied consists of the two-electronic energy levels ( 3 H 4 and 3 H 6 ) of Tm 3+ doped in YAG crystal. When a two-level atom at an arbitrary superposition state is excited by a pair of specially designed laser pulses, the excited state component gains a relative phase with respect to the ground state component. We identified the phase shift to be of pure geometric nature. The dynamic phase associated to the driving Hamiltonian is unchanged. The experiment results of the phase change agree with the theory to the extent of the measurement limit.
Diffraction by a Circular Aperture

This paper deals with approximations to Andrews’ semi-empirical expression for the relative electric amplitude along the magnetic diameter in the plane of a circular aperture. These approximations yield analytic solutions in the form of zeroth- and second-order cylindrical Bessel functions: E/E0=1−(e−jω/2)[J0(δ)−J2(δ)],where ω = πD/λ, δ = 2πx/λ, D is diameter of aperture, x is the distance from the center of the aperture, and λ is the wavelength of the incident plane wave. Of special interest are the cases of integral D/λ in which e−jω becomes plus and minus one as D/λ is even and odd, respectively. For cases of D/λ = 20 and D/λ = 4, the approximation is good over half the aperture. The results give a physical picture of interference among three traveling waves, the incident plane wave and two waves from the edge that are essentially cylindrical in nature.A treatment of multiple reradiation based on the above physical picture led to the conclusion that it was not significant for apertures with diameters greater than one wavelength.
Probabilistic Analysis of Graph Algorithms

Probabilistic Analysis of Graph Algorithms. We review some of the known results on the average case performance of graph algorithms. The analysis assumes that the problem instances are randomly selected from some reasonable distribution of problems. We consider two types of problem. The first sort is polynomially solvable in the worst case but there are algorithms with better average case performance. In particular we consider the all-pairs shortest path problem, the minimum spanning tree problem, the assignment problem and the cardinality matching problem in sparse graphs. Our second category of problems consists of problems which seem hard in the worst-case but still have algorithms with good average case performance. In particular we consider three NP-Complete problems; the Hamilton cycle problem, the graph bisection problem and graph colouring. In addition we consider the graph isomorphism problem whose exact complexity is still undetermined.
New mafia: Black, hispanic and italian styles

Organized crime is a functional part of the Ameri-can social system and, while successive waves of immigrants and migrants have found it an available means of mobility, it transcends the involvement of any particular group and even changing definitions of legality and illegality in social behavior.
ARE “GREEN TIDES” HARMFUL ALGAL BLOOMS? TOXIC PROPERTIES OF WATER-SOLUBLE EXTRACTS FROM TWO BLOOM-FORMING MACROALGAE, ULVA FENESTRATA AND ULVARIA OBSCURA (ULVOPHYCEAE)

Toxic properties are more often associated with microalgal blooms than with macroalgal blooms, although herbivore deterrents are well known in macroalgae, and inhibition of invertebrate larval development by extracts from Ulva spp. has been suggested. This study was prompted from our observation that substantial discoloration of seawater occurred in small bays after mass desiccation-induced mortality of Ulvaria obscura (Kutzing) Gayral. We examined the effects of extracts from Ulva fenestrata Postels et Ruprecht and Ulvaria obscura on Fucus gardneri Silva zygote development, growth of Ulva and Ulvaria , epiphytic algal accumulation, and oyster larval development. Fucus zygote development was inhibited by extracts from both species, although the effects of Ulvaria extracts were significantly greater. Epiphytic algal accumulation and the growth of Ulva and Ulvaria were inhibited by extracts from both species. Oyster larval development was arrested by the presence of extracts from each species. We conclude that extracts from both Ulva fenestrata and Ulvaria obscura have allelopathic properties. The effects are more widespread and occur at lower concentrations for extracts from Ulvaria than Ulva. These properties could alter competitive interactions by inhibiting germination or development of algae and invertebrates.
Partial Cystectomy after Neoadjuvant Chemotherapy: Memorial Sloan Kettering Cancer Center Contemporary Experience.

Objective. To report our contemporary experience with partial cystectomy after neoadjuvant chemotherapy. Patients and Methods. Retrospective review of patients who underwent neoadjuvant chemotherapy and partial cystectomy for urothelial cell carcinoma of the bladder at Memorial Sloan Kettering Cancer Center from 1995 to 2013. Log-rank test and Cox regression models were used to analyze variables possibly associated with recurrence-free, advanced recurrence-free (free from recurrence beyond salvage with intravesical therapy or radical cystectomy), and overall survival. Results. All 36 patients had a solitary tumor <5 cm in size. Twenty-one patients (58%) achieved cT0 following neoadjuvant chemotherapy with 7 (33%) having residual disease at PC. At last follow-up, 19 (53%) patients had recurrence, 15 (42%) had advanced recurrence, 10 (28%) died of disease, and 22 (61%) maintained an intact bladder. Median follow-up of those who were with no evidence of disease was 17 months. On univariable analysis, after neoadjuvant chemotherapy positive nodes on imaging and positive surgical margin at partial cystectomy were both associated with worse recurrence-free, advanced recurrence-free, and overall survival. Five-year recurrence-free, advanced recurrence-free, and overall survival were 28%, 51%, and 63%, respectively. Conclusion. Partial cystectomy following neoadjuvant chemotherapy provides acceptable oncologic outcomes in highly selected patients with muscle-invasive bladder cancer.
Porphyria cutanea tarda and hepatitis C virus: a case-control study and meta-analysis of the literature.

Abstract Background: Porphyria cutanea tarda (PCT) and hepatitis C virus (HCV) infection have been associated in several reports with the prevalence of HCV exhibiting considerable regional variation. However, most reports were confounded by selection bias and a regional prevalence of HCV in the populations studied. In the United States, only a few cases of this association have been reported to date. Objective: We conducted a study to evaluate the association between PCT and HCV in a US population. We used a case-control study design to control the systemic error that may occur during a selecting process or sampling procedure. Methods: We reviewed the medical records of Wishard Memorial Hospital, a county hospital serving metropolitan Indianapolis, Indiana, to perform a retrospective case-control study of 26 patients with PCT (as case) against 149,756 regional volunteer blood donors (as control-1) and 51 patients receiving methotrexate for psoriasis (as control-2). HCV antibody titers and other liver abnormalities were our main outcome measures. We then performed a weighted meta-analysis of 17 reports that had at least 17 patients in their study populations. Results: Sixteen (94%) of 17 PCT patients tested for HCV were antibody positive. Among blood donors, only 255 or 0.17% were HCV antibody positive ( P P = .0002, two-sided Fisher's exact test). For geographic comparison, meta-analysis of the literature demonstrated a varying regional prevalence of HCV in PCT patients as follows: Northern Europe 17%, Australia/New Zealand 20%, and Southern Europe 65%. Conclusion: Although a marked geographic variation was found in the worldwide prevalence of HCV in PCT patients, a very large percentage of US patients with PCT had HCV infection. Our results emphasize the need for clinicians to actively look for HCV in patients with PCT. (J Am Acad Dermatol 1999;41:31-6.)
Acute leukemia with t(10;11)(p11-p15;q13-q23)

Abstract We report six patients with acute leukemia characterized by the presence of a t(10;11) (p11-p15;q13-q23), either as sole cytogenetic abnormality (three patients) or as part of a complex abnormal karyotype. The morphologic and cytochemical features of four patients were consistent with FAB-M5A, while two patients presented with FAB-L1 characteristics. By immunophenotyping, myeloid leukemia was diagnosed in five patients, including one patient with FAB-L1 leukemia who typed as terminal transferase (TdT) + , CD7 T-cell antigen + acute myelomonocytic leukemia. Differentiated acute myeloid leukemia (AML) with expression of terminal transferase was found in two of the other cases and monocytic leukemia in two, with co-expression of T-cell antigens in one of them. The second FAB-L1 patient typed as undifferentiated acute lymphocytic leukemia (ALL) expressing myeloid antigens. Serial phenotypic studies in patient 3 during the course of the disease demonstrated a switch from monocytic to lymphoid morphology at the time of first and second relapse, which was paralleled by the appearance of a pre-T ALL immunophenotype with co-expression of the myeloid antigen CD33. These phenotypic changes occurred without apparent alteration in the genotype since t(10;11)(p11.2;q23) remained the only cytogenetic aberration at all stages of the disease. Our observations suggest that the (10;11) variant of 11q aberrations occurs in a bipotential myelomonocytic/T-lymphoid stem cell.
Localized corrosion behavior of a zirconium-based bulk metallic glass relative to its crystalline state

Abstract To date, few detailed corrosion studies of the new bulk metallic glasses (BMGs) have been presented. In the present work, the aqueous electrochemical corrosion properties of BMG-11, 52.5Zr–17.9Cu–14.6Ni–5.0Ti–10.0Al (atomic percent), were investigated. Cyclic-anodic-polarization tests were conducted on amorphous and crystalline specimens in a 0.6 M NaCl solution (simulated seawater) and on amorphous specimens in a 0.05 M Na 2 SO 4 solution (simulated moisture condensation, as related to ongoing fatigue experiments in humid air), all at room temperature. In the NaCl solution, both amorphous and crystalline materials were found to exhibit passive behavior with low corrosion rates (15 μm/year or less). However, susceptibilities to pitting corrosion were observed. The amorphous material was found to be more resistant to the onset of pitting corrosion under natural corrosion conditions. In the 0.05 M Na 2 SO 4 solution, the amorphous BMG-11 was found to exhibit passive behavior with a very low corrosion rate (0.4 μm/year), and to be immune to pitting corrosion. Furthermore, when the protective passive film was removed by scratching with a diamond stylus, it was found to quickly reform. This result suggested that a corrosion influence on the fatigue properties of BMG-11 in humid air would be minimal.
Flow cytometric investigation of neutrophil activation pathways by n-formyl-Met-Leu-Phe and phorbol myristate acetate

Summary Recent evidence suggests that multiple pathways exist in PMN activation and that specific leukocyte response may be due to the activation of a particular signaling pathway. Using flow cytometry, PMN activation pathways were studied through the parallel comparison of n-formyl-Met-Leu-Phe (fMLP)- and phorbol-12-myristate-13-acetate (PMA)-induced stimulation and by simultaneous assays for CD11b expression and morphology. The maximal CD11b expression was higher with PMA than with fMLP, suggesting different activation pathways. Under these experimental conditions, a morphological response to fMLP was not observed. However, significant shape change was detected in PMA treated samples and was suppressed by either the removal of extracellular calcium or staurosporine at the concentrations above 14.5 μM. Calcium ionophore induced a similar light scattering pattern to that by PMA and enhanced CD11b expression, both of which were not inhibitable by staurosporine. These observations, for the first time, indicated that Ca2+ was a mediator in activation processes and that the treatment of PMN with PMA resulted in Ca2+ influx.
Analysis of Headache Management in a Busy Emergency Room in the United States

Objectives.— To analyze the demographics, diagnosis, and treatment patterns in patients with headache-seeking treatment in one of the busiest emergency rooms (ER) of an academic medical center in the USA. Background.— The past decade has seen tremendous improvement in acute and preventive management of headaches. However, there are very few data on how headache patients are managed by ER doctors. Methods.— Retrospective analysis of 100 charts chosen at random for patients with a discharge diagnosis of headache (according to ICD-9 codes) from the University of Southern California + Los Angeles County Hospital ER. Results.— The majority of patients were female (74%) and Hispanic (76%) with an age range of 15-68 years. The most common ER diagnoses were migraine (42%) and headache not otherwise specified (headache NOS – 42%). Fifty-one percent of patients received a head computerized tomography; 9% received a lumbar puncture. Medications most frequently used for acute treatment, whether migraine or headache NOS, were narcotics (25%), followed by antiemetics (24%), nonsteroidal anti-inflammatory drugs (19%), and acetaminophen (17%). Only 5% of migraine patients received migraine-specific triptans in the ER (2% overall). Thirty-one percent of migraineurs were given a prescription for a triptan upon discharge from the ER (17% of all patients). Eighteen percent of patients were admitted to the hospital with secondary headache. The final diagnosis in the ER matched the diagnosis of the neurologist in 79% of cases with a moderate degree of agreement. Conclusion.— Narcotics remain the medications most often chosen for treatment of all acute headaches (including migraine) in the ER. There is very little use of migraine-specific medications in the ER. In addition, neurology consults are underutilized even in an academic setting in the ER. The data suggest a lack of clear standards of care for diagnosis and treatment of headache, especially migraines. Specific guidelines for headache management should be established keeping in mind the unique setting of the ER.
A multilayer ultracold neutron turbine source for a long-pulse spallation source

Abstract We have developed a concept for an ultracold neutron (UCN) turbine source based on a long-pulse spallation source. Using a single reflection from a receding blade, the turbine converts cold neutrons from the primary moderator to UCN. The UCN pulse length is spread out in time and is comparable to the primary pulse interval, producing a quasi-continuous UCN source. The principal parameters for such a design are the primary source pulse length, the flight path distance, and the velocity acceptance interval of the reflector. Taking advantage of recent advances in multilayer reflector preparation, we propose W11B4C multilayer reflectors with a high-reflectivity plateau in the velocity range of 80±5 m/s. We have simulated a multilayer turbine which converts 160±5 m/s neutrons from a 1 ms primary source with a 2.5 m incident flight path to UCN with an efficiency, in terms of phase space density, of about 4.4%. For a ∼1 MW long-pulse spallation source with 1 ms pulse length and 60 Hz frequency, and a time average flux in a liquid hydrogen moderator of 1 × 1014 n/cm2 s, this corresponds to a UCN source flux of 1.9 × 105 n/cm2 s, a total UCN current of 3.3 × 107 n/s, and a UCN density (for velocity ≤6.2 m/s) of 500 n/cm3.
Distribution coefficient algorithm for small mass nodes in material point method

When using the time explicit material point method to simulate interaction of materials accompanied by large deformations and fragmentation, one often encounters a numerical instability caused by small node mass, because acceleration on a mesh node is obtained by dividing the total force on the node by the mass of the node. When the material points are in the far sides of the cells containing the node, typically happening near material interfaces, the node mass can be very small leading to artificially large acceleration and then numerical instability. For the case of small material deformations, this instability is typically avoided by placing the material points away from cell boundaries. For cases with large deformations, with the exception of initial conditions, there is no control on locations of the material points. The instability caused by small mass nodes is often encountered. To avoid this instability tiny time steps are usually required in a numerical calculation. In this work, we present a numerical algorithm to treat this instability. We show that this algorithm satisfies mass and momentum conservation laws. The error in energy conservation is proportional to the second order of the time step, consistent with the explicit material point method. Numerical implementation of the algorithm is described. Numerical examples show effectiveness of the algorithm.
Substance abuse is a significant marker for perinatal morbidity in a population of women with poor prenatal care in Washington, DC

Poor prenatal care (PNC) is an important risk factor for perinatal morbidity. This study defines the additive risk of substance abuse (SA) during pregnancy in a population of 480 D.C. residents with no/poor PNC. Poor PNC was identified if care was initiated after 24 weeks, or less than 5 visits. 35% of these post partum women showed evidence of substance abuse during pregnancy by history and/or urine testing. The two groups are compared below (results expressed as mean ±S.E.M.) The relative risk (RR) for prematurity in women with SA and no/poor PNC was 2.7, (95% C.I. = 1.6-3.8, p<0.0001). The attributable risk fraction (ARF) for LBW associated with SA in this population was 31%. The RR for LBW in women with SA and no/poor PNC was 2.6 (95% C.I. = 1.5-3.63, p<0.0001). The ARF for prematurity associated with SA in this population was 32%. We conclude that women with no/poor PNC who abuse substances during pregnancy are at exquisitely high risk for poor outcomes and deserve to be targeted specifically in programs designed to reduce perinatal/neonatal morbidity and mortality. Table
Comparison of the ACL and ACL graft forces before and after ACL reconstruction an in-vitro robotic investigation

Background Long-term follow-up studies have indi-cated that there is an increased incidence of arthrosis following anterior cruciate ligament (ACL) reconstruc-tion, suggesting that the reconstruction may not repro-duce intact ACL biomechanics. We studied not only the magnitude but also the orientation of the ACL and ACL graft forcesMethods 10 knee specimens were tested on a robotic testing system with the ACL intact, deficient, and recon-structed (using a bone-patella tendon-bone graft). The magnitude and orientation of the ACL and ACL graft forces were determined under an anterior tibial load of 130 N at full extension, and 15, 30, 60, and 90° of flexion. Orientation was described using elevation angle (the angle formed with the tibial plateau in the sagit-tal plane) and deviation angle (the angle formed with respect to the anteroposterior direction in the transverse plane)Results ACL reconstruction restored anterior tibial translation to within 2.6 mm of that of the intact knee under the 130-N anterior ...
Collective Wisdom: A Modest Proposal to Improve Peer Review, Part 1

Not all authors appreciate the rules for overlapping manuscript submissions, but we might be able to improve the process for the future.
cis Effects in Adeno-Associated Virus Type 2 Replication

We have utilized deletion mutants of adeno-associated virus (AAV) to investigate which elements of the AAV genome are required in cis for high yields of the wild-type virus in a plasmid transfection assay and in addition whether these elements affect primarily AAV DNA replication or encapsidation. All tested deletions from within the Rep region demonstrated a modest, approximately threefold, decrease in viral production. Deletions within the cap region resulted in markedly less virus. Previous observations suggested that in cells in which recombinant AAV (rAAV) was produced, as in our assay with the helper plasmid pDG, there is a substantial excess of empty capsids. Co-transfections of high- and low-yielding constructs demonstrated that under conditions where Cap is abundant, the constructs with cap deletions did not package efficiently. These observation suggest that the lower yields of rAAV cannot be entirely due to lack of capsids but that elements within the cap region of the wild-type genome are important for efficient encapsidation. The production of virus by the mutants we tested was, however, not consistent with the disruption of a cis-acting packaging signal. Apparently, when Cap is provided "in trans," encapsidation is inefficient. A second observation is that there were equivalent amounts of replicated but unencapsidated viral DNA in cells transfected with each of our constructs. We propose that, in accord with the previously proposed link between DNA replication and encapsidation, the total amount of AAV DNA replication can be limited by the efficiency of encapsidation.
Pinto fires and personal ethics: A script analysis of missed opportunities

This article details the personal involvement of the author in the early stages of the infamous Pinto fire case. The paper first presents an insider account of the context and decision environment within which he failed to initiate an early recall of defective vehicles. A cognitive script analysis of the personal experience is then offered as an explanation of factors that led to a decision that now is commonly seen as a definitive study in unethical corporate behavior. The main analytical thesis is that script schemas that were guiding cognition and action at the time precluded consideration of issues in ethical terms because the scripts did not include ethical dimensions.
The plane with parallel coordinates

By means ofParallel Coordinates planar “graphs” of multivariate relations are obtained. Certain properties of the relationship correspond tothe geometrical properties of its graph. On the plane a point ←→ line duality with several interesting properties is induced. A new duality betweenbounded and unbounded convex sets and hstars (a generalization of hyperbolas) and between Convex Unions and Intersections is found. This motivates some efficient Convexity algorithms and other results inComputational Geometry. There is also a suprising “cusp” ←→ “inflection point” duality. The narrative ends with a preview of the corresponding results inR N .
A hybrid nonlinear-least squares estimation of harmonic signal levels in power systems

It is expected that guides and recommended practices will be adopted in the United States for the limitation of harmonic currents and voltages in electric power systems. A method of using measurements and topological/mathematical methods to identify signal levels that do not comply with these guides and standards is described. The methodology is based on measurements, state estimators, and system modeling. An illustration of its application is given. A hybrid nonlinear-least-squares method is used for state estimation. This estimation theory is used to calculate (estimate) bus voltages and line currents which cannot be (or are not) measured directly. The basis for the least-squares estimator is the Kirchhoff current law, and the basis for the nonlinear technique is minimum mismatch power. >
Model complexes suggest certain S-state changes of the photosynthetic water-oxidation enzyme may involve an Mn(II)−Mn(III) transition

Abstract The ultraviolet-visible absorbance differences spectra of Mn(II,III) and Mn(III,III) oxo-bridged carboxylate complexes are reported. The difference spectra are remarkably similar to those of the photosynthetic water-oxidation enzyme complex reported by Dekker et al. [(1984) Biochim. Biophys. Acta 764, 301–309] which were interpreted as being due exclusively to Mn(II→IV) transitions. This result indicates that certain S-state changes of the enzyme complex may instead involve Mn(II→III) transitions, and that difference spectra alone cannot be used with confidence to assign the Mn oxidation state changes during water oxidation.
The influence of cyclic loading on the lithium corrosion behavior of reactor materials

Abstract A review of the frequency dependent fatigue-crack-propagation characteristics of 2 1 4 Cr — 1 Mo steel and types 304 and 304L stainless steel shows that liquid lithium enhances crack growth rates in the temperature range of 473K to 973K. These results are significantly different from data for sodium obtained previously by other investigators. A mechanistic interpretation of the effects of lithium indicates that lithium enhances crack growth by inducing embrittlement at low temperatures and by grain boundary penetration at high temperatures. The engineering implications of this study are discussed.
Seismology: the start of something big?

Can we predict the final size of an earthquake from observations of its first few seconds? An extensive study of earthquakes around the Pacific Rim seems to indicate that we can — but uncertainties remain. In the cascade model, a widely accepted explanation of earthquake initiation, slip initiates on a small fault patch and continues to rupture along a fault plane if conditions are favourable. The implications of this domino-like theory are that a small earthquake begins in the same way as a large one, and that the size of an earthquake cannot be determined until the rupture stops. Olson and Allen now suggest that processes during earthquake initiation do control the final magnitude to some degree. They find a scaling relation between the frequency content of energy radiated in the first few seconds of rupture and earthquake magnitude. Understanding the physics of this process may make it possible to predict the magnitude of earthquakes without knowing the surrounding state of stress on a fault.
Spatial and temporal distribution of iron in the surface water of the northwestern Atlantic Ocean

Abstract The spatial and temporal distribution of three size fractions ( 0.2 μm Fe fraction). Concave 0.2 μm Fe in the shelf water may have important implications for estimating riverine Fe inputs to the open ocean. Maximum concentrations of >0.2 μm Fe (1.5–3.5 nM) and major nutrients were observed at the shelf/ slope front, probably due to enhanced vertical mixing and convergence circulation at the frontal zone. Significant temporal variations in Fe concentrations were also observed. In March 1993, enhanced riverine discharge, vertical mixing, and bottom resuspension contribute to significantly higher Fe concentration in shelf waters than in other seasons. Seaward advective Fe transport from the continental shelf leads to elevated Fe concentrations in offshore waters at this time.
Are the Chesapeake Bay waters warming up

1. Apparently significant trends within moderately long (50-year) series of meteorological or hydrological data should be regarded with suspicion until justified on the basis of much longer term information. 2. Extra efforts should be directed toward securing the continuance of routine observations at stations where long data histories are already available and where the termination of such records might be regretted at some future time. 3. Mean annual air and water temperatures at different sites may be quite highly correlated even when the points of measurement are very widely separated. 4. The annual average water temperature at one station close to the Chesapeake Bay appears to be normally distributed with a standard deviation of 0.7°C about a stationary overall mean value of 14.6°C. Its 1000-year departure is ±2.2°C.
Intermolecular energy transfer across nanocrystalline semiconductor surfaces.

The yields and dynamics for energy transfer from the metal-to-ligand charge-transfer excited states of Ru(deeb)(bpy)2(PF6)2, Ru2+, and Os(deeb)(bpy)2(PF6)2, Os2+, where deeb is 4,4‘-(CH3CH2CO2)2-2,2‘-bipyridine, anchored to mesoporous nanocrystalline (anatase) TiO2 thin films were quantified. Lateral energy transfer from Ru2+* to Os2+ was observed, and the yields were measured as a function of the relative surface coverage and the external solvent environment (CH3CN, THF, CCl4, and hexanes). Excited-state decay of Ru2+*/TiO2 was well described by a parallel first- and second-order kinetic model, whereas Os2+*/TiO2 decayed with first-order kinetics within experimental error. The first-order component was assigned to the radiative and nonradiative decay pathways (τ = 1 μs for Ru2+*/TiO2 and τ = 50 ns for Os2+*/TiO2). The second-order component was attributed to intermolecular energy transfer followed by triplet−triplet annihilation. An analytical model was derived that allowed determination of the fraction ...
Theoretical analysis of equivalency of high-power diode laser (810 nm) and Nd:YAG laser (1064 nm) for coagulation of tissue: predictions for prostate coagulation

Profiles of light, temperature, and thermal damage distributions in tissue based on measured optical properties are examined theoretically for high power diode laser (810 nm) and Nd:YAG laser 1064 nm). Generally higher absorption and effectively lower optical penetration has been experimentally observed at the wavelength of diode laser as compared to that of Nd:YAG laser. Results of this study indicate that similar thermal damage volumes are expected to be obtained by the two lasers, in general. However, for same irradiation conditions a larger volume of damage and more charring near the surface is predicted when using the diode laser on prostate tissue, and similarly for myocardial tissue. Role of blood presence throughout tissue, in terms of its optical interaction, as well as the role of a small layer of blood between the laser and the tissue is also investigated for both wavelengths.
Influence of sub-micron surface patterns on the deposition of model proteins during active filtration

In this study, the effects of sub-micron surface patterns on the fouling of a model protein solution (bovine serum albumin (BSA)), was investigated during active filtration and simple adsorption conditions. Surface patterns were created directly onto a commercial polyethersulfone ultrafiltration membrane using nanoimprint lithography, which resulted in a moderately reduced molecular mass cut-off (MWCO) but similar permeance as its non-imprinted counterpart as well as significantly improved resistance to BSA fouling. Staged filtration experiments, with backwash cleaning, revealed that the permeate flux of the imprinted membrane was considerably higher than that of the non-imprinted membrane, consistent with UV–vis measurements showing less protein deposition on the imprinted membranes. This improvement in anti-fouling characteristics for the imprinted membrane was universally observed for varying feed-solution chemistry including changes in both pH and ionic strength. From controlled protein-adsorption experiments under non-filtration conditions, it appears that the observed decrease in protein adsorption on the imprinted membranes is likely associated with altered hydrodynamics due to the presence of the sub-micron patterns.
A budget model of a university

Abstract Yale University operates a number of budget systems for purposes of planning and control. These include a capital budget, a cash budget, an operating budget, and an operating growth budget. The operating growth budget might be the one of most potential interest to people concerned with Operations Analysis in Education. The operating growth budget is a model of what the University fiscal flows and structure might look like under varying conditions over an extended period, e.g., 20 years. It is composed of a set of ideas, a set of equations, and a computer program. It is important to us to point out that this work is in a development stage. We have run many simulations, adjusted the program, refined the parameter estimates, and modified the questions we have been asking. Part of our efforts have followed a concern that we have captured the appropriate structure, part that we are investigating our own spectrum of decisions, and part that we can reflect the varying “external” conditions outside of the University's immediate influence and control. Our work with the operating growth budget has already started to influence some of the decisions of the University including the yearly operating budget, the capital funds programs, and the endowment investment portfolio.
TU-D-352-09: Development of a Carbon-Nanotube Field Emission Based Multi-Pixel Microbeam Cellular Irradiation System

Purpose: High spatial and temporal resolution cellular microbeam irradiation is important in studying dynamic radiation response at the cellular level. Existing systems include charged particle, x‐ray, and electron single beamirradiators. We have proposed a multi‐pixel electron microbeam array irradiator based on carbon nanotube(CNT)field emission with individually controllable beams to irradiate cellular scale regions in a Petri dish under real time microscope observation. Method and Materials: We have developed and tested a prototype single pixel 30keV electron irradiator utilizing a CNTfield emissioncathode. The cathode is temporally modulated to deliver a calibrated electron dose to the target. Microfabrication methods are used to develop beamcollimators of fine aperture. Dosimetry is performed using GAFCHROMIC film, and system feasibility is demonstrated via Rat‐1 cell line irradiation. A multi‐pixel system with a cathode chip and electron transparent window has been built, and the multi‐pixel method has been demonstrated via field emissiontesting.Results: Preliminary data show the CNT electron microbeam irradiator is capable of 100 Gy/sec dose rate and 23um beam diameter. An “L” shaped irradiation pattern was used in feasibility demonstration using plated Rat‐1 cells. Irradiation was visualized via Gamma‐H2AX fluorescence marking of DNA damage. The multi‐pixel microbeam concept has been demonstrated through fabrication and testing of a 5×5 microbeam array cathode. A 2.5mA field emission current was achieved with all pixels emitting. Conclusion: We have demonstrated the feasibility of a carbon nanotubefield emission based single microbeam cellular irradiation system as well as the cathode fabrication for the multi‐pixel microbeam prototype system still under development. The CNT microbeam irradiator is capable of delivering radiation over a large dynamic dose rate range with high temporal resolution. The eventual CNT based cellular irradiator is expected to be compact and made available for broad application.
Regulation of blood meal size in the mosquito.

Abstract In order to determine the role played by the central nervous system in regulating blood meal size, the ventral nerve cord was cut at various sites along its length in the female mosquito, Aedes aegypti. When the cord was cut anterior to the second abdominal ganglion, massive hyperphagia resulted, many females ruptured, and blood intake was more than four times that of the untreated controls. As the site of the operation was moved stepwise posteriorly leaving more ganglia connected to the brain via the ventral nerve cord, the degree of hyperphagia and quantity of ingested blood was reduced. On the basis of these observations it was concluded that the termination of feeding was initiated by segmental abdominal stretch receptors which act in concert and signal the presence of optimal blood meal volume to the brain. Five additional mosquito species were tested for hyperphagia and all ingested three to four times the normal blood meal volume when the ventral nerve cord was cut. Females with the nerve cord severed showed normal ovarian development and egg formation, but oviposition was inhibited.
Measurements Of Refractive Index Spectra Over Snow

Over a snow-covered field, I have measured time series of the turbulent fluctuations in temperature and humidity with a fine-wire platinum resistance thermometer and a Lyman-alpha hygrometer. From these time series I computed temperature and humidity spectra and temperature-humidity cospectra. When properly summed, these spectra and cospectra yielded refractive index spectra for visible and millimetre wavelengths, the first such spectra ever collected over snow.