cssi/SciSciGPT-SciSciNet huggingface dataset:
Distinct short-range ovule signals attract or repel Arabidopsis thaliana pollen tubes in vitro

Pollen tubes deliver sperm after navigating through flower tissues in response to attractive and repulsive cues. Genetic analyses in maize and Arabidopsis thaliana and cell ablation studies in Torenia fournieri have shown that the female gametophyte (the 7-celled haploid embryo sac within an ovule) and surrounding diploid tissues are essential for guiding pollen tubes to ovules. The variety and inaccessibility of these cells and tissues has made it challenging to characterize the sources of guidance signals and the dynamic responses they elicit in the pollen tubes. Here we developed an in vitro assay to study pollen tube guidance to excised A. thaliana ovules. Using this assay we discerned the temporal and spatial regulation and species-specificity of late stage guidance signals and characterized the dynamics of pollen tube responses. We established that unfertilized A. thaliana ovules emit diffusible, developmentally regulated, species-specific attractants, and demonstrated that ovules penetrated by pollen tubes rapidly release diffusible pollen tube repellents. These results demonstrate that in vitro pollen tube guidance to excised A. thaliana ovules efficiently recapitulates much of in vivo pollen tube behaviour during the final stages of pollen tube growth. This assay will aid in confirming the roles of candidate guidance molecules, exploring the phenotypes of A. thaliana pollen tube guidance mutants and characterizing interspecies pollination interactions.
More Dam Process: Relicensing of Dams and the 2005 Energy Policy Act

Every hydropower facility in the Nation not operated by the federal government must obtain an operating license from the Federal Energy Regulatory Commission (FERC) if that facility affects interstate commerce, navigable waterways, or meet other criteria. . . . License renewal, called "relicensing," occurs only once every 30 to 50 years. Each time a license is issued or renewed the process provides an opportunity for any interested stakeholder to earn legal standing and influence the terms of the next license. Because a license term lasts for decades, dams seeking license renewal today were effectively grandfathered from complying with existing environmental laws and standards. Thus, relicensing is a significant opportunity to address a hydropower dam's environmental footprint and to weigh the commitment of watershed resources for another 30 to 50 years.
A lecture on the averaging process

Author(s): Aldous, D; Lanoue, D | Abstract: To interpret interacting particle system style models as social dynamics, suppose each pair {i, j} of individuals in a finite population meet at random times of arbitrary specified rates vij, and update theirstates according to some specified rule. The averaging process has real-valued states and the rule: upon meeting, the values Xi(t-),Xj (t-) arereplaced by 1/2 (Xi(t-) + Xj (t-)), 1/2 (Xi(t-) + Xj (t-)). It is curious this simple process has not been studied very systematically. We provide an expository account of basic facts and open problems.
Cerebral malaria: a diagnostic dilemma. A case report.

Abstract The following report describes an adolescent patient with falciparum malaria, who was initially seen in a florid psychotic state. Formulation of a diagnosis necessitated differentiation among three diagnostic possibilities: a coincidental functional psychosis, cerebral malaria, or cerebral malaria acting as the precipitating factor for a functional psychosis in a predisposed personality.
Verification and validation of Mars Exploration Rover surface capabilities

This paper will discuss the system level verification and validation test program for the surface capability of the Mars Exploration Rovers (MER). The Mars Exploration Rover project was implemented on an extremely challenging schedule of going from concept to launch in just three years. Although the cruise and entry, descent and landing (EDL) systems were based on the successful Mars Pathfinder mission of 1997, the MER rovers and their sophisticated science payload were a new development and the expectations for the surface capability were very high. The rover hardware and software were developed to allow certain functions to work in parallel to maximize the science that could be done each day on Mars. However this lead to complex behavioral interactions which had to be tested and verified before they could be used. An incremental test program was developed that first exercised and verified individual functions and then validated system capabilities in mission-like scenarios. The plans, execution and results of these mission-like surface system tests will be presented.
The Unofficial Macintosh Guide to America Online

Installing or Reinstalling the America Online Software Navigating on America Online Using System Logs to Capture Text Using the Message Boards E-Mail E-Mail via FlashSessions Using E-Mail to Transfer Files with Persons Not on AOL Downloading Files on AOL AOL and the Internet Chatting, Instant Messages, and Parental Control When Things Go Wrong on AOL A Few Tips for Macintosh Users Modems Appendix Index.
Retrograde Thoracic Duct Embolization in a Pediatric Patient with Total Cavopulmonary Connection and Plastic Bronchitis

review in general surgery, the frequency and the type of errors in the operating theater were estimated. Reviewing 28 quantitative articles, the authors demonstrated a median of 15.5 errors per operation, 23.5% of which were equipment related (7). Surgical techniques that relied more on new technologies had a higher proportion of equipment-related errors. Our search retrieved three studies assessing the frequency of errors before and after a suggested intervention. The paucity of data analyzed makes it difficult to draw any generalizable conclusions and calls for more research into safety in IR. Nontechnical, preventable failures account for two-thirds of intraprocedural errors in the angiography suite. These errors are due at least in part to suboptimal communication among the IR team. The unavailability of equipment is common and is due to inadequate planning and lack of communication between the operator and individuals responsible for equipment stock. None of the studies assessed the entire journey of the patient, highlighting the need for a more comprehensive study of the IR care pathway from admission to discharge. Morbi et al (4) reported 2,040 errors in 55 IR procedures in the period before intervention. In contrast, Koetser et al (5) identified only 67 errors during a similar period in 94 IR procedures, whereas Lutjeboer et al (6) reported 50 errors in 220 procedures. The difference may be due to many reasons, including different thresholds for recording medical errors. The predefined nature of the recorded errors may also explain the discrepancy. In addition, only Morbi et al (4) addressed the intraprocedure period, when most errors are likely to occur. The complex intraprocedure interactions among the different team members and continuously developing equipment technologies create a fertile environment for medical errors to occur. The lack of standardization in medical error reporting is a major shortcoming in current and future studies concerned with errors in IR. Standardized error reporting and a complications registry would facilitate larger multicenter studies, which would help identify the most common errors and vulnerabilities in the IR care pathway. Identifying vulnerabilities will, in turn, help develop strategies for error prevention. In conclusion, in the studies retrieved, it appears that the frequency of medical errors in IR is comparable to surgical disciplines and that errors can be reduced with improvement strategies. Overall, however, IR literature lacks research concerned with medical errors and patient safety outcomes. It is paramount for the IR community to react to this and investigate the incidence of medical errors at all phases of the IR pathway. In addition, it is crucial to devise strategies to reduce these failures and maintain a safe IR practice.
Giants in Chest Medicine: John F. Murray, MD

ABOUT THE AUTHOR/AFFILIATIONS: Philip C. Hopewell, MD, is from the Division of Pulmonary and Critical Care Medicine, San Francisco General Hospital, University of California, San Francisco. CONFLICT OF INTEREST: None declared. CORRESPONDENCE TO: Philip C. Hopewell, MD, San Francisco General Hospital, Room 5K1, San Francisco, CA 94110; e-mail: phil. hopewell@ucsf.edu ADDITIONAL INFORMATION: See video interview of Dr Murray online at http://dx.doi.org/10.1378/chest.15-2005 . © 2015 AMERICAN COLLEGE OF CHEST PHYSICIANS. Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details. DOI: 10.1378/chest.15-2005 [ Giants in Chest Medicine ]
Genomics in the clinic: ethical and policy challenges in clinical next-generation sequencing programs at early adopter USA institutions

Next-generation sequencing (NGS) technologies are poised to revolutionize clinical diagnosis and treatment, but raise significant ethical and policy challenges. This review examines NGS program challenges through a synthesis of published literature, website and conference presentation content, and interviews at early-adopting institutions in the USA. Institutions are proactively addressing policy challenges related to the management and technical aspects of program development. However, ethical challenges related to patient-related aspects have not been fully addressed. These complex challenges present opportunities to develop comprehensive and standardized regulations across programs. Understanding the strengths, weaknesses and current practices of evolving NGS program approaches are important considerations for institutions developing NGS services, policymakers regulating or funding NGS programs and physicians and patients considering NGS services.
Effect of the Stone–Wales defect on the structure and mechanical properties of single-wall carbon nanotubes in axial stretch and twist

The effect of the Stone–Wales defect due to the rotation of a pair of neighboring atoms on the equilibrium structure and mechanical properties of single-wall carbon nanotubes in axial stretch and twist is considered. The position of carbon atoms in a test section consisting of a number of repeated units hosting a solitary Stone–Wales defect is computed by minimizing the Tersoff–Brenner potential. The energy invested in the defect is found to decrease as the radius of the nanotube becomes smaller. Numerical computations for nanotubes with zigzag and armchair chiralities show that inclined, axial, and circumferential defect orientations have a strong influence on the mechanical response in axial stretch and twist. Stretching may cause the defect energy to become negative, revealing the possibility of spontaneous defect formation leading to failure. In some cases, stretching may eliminate the defect and purify the nanotube. When the tube is twisted around its axis, a neck develops at the location of the defect, signaling possible disintegration.
A Simulation Study of Alternatives to Ordinary Least Squares

Abstract Estimated regression coefficients and errors in these estimates are computed for 160 artificial data sets drawn from 160 normal linear models structured according to factorial designs. Ordinary multiple regression (OREG) is compared with 56 alternatives which pull some or all estimated regression coefficients some or all the way to zero. Substantial improvements over OREG are exhibited when collinearity effects are present, noncentrality in the original model is small, and selected true regression coefficients are small. Ridge regression emerges as an important tool, while a Bayesian extension of variable selection proves valuable when the true regression coefficients vary widely in importance.
Mannitol Stimulates Atrial Natriuretic Peptide Release in Humans

The purpose of this study was to determine if mannitol stimulates atrial natriuretic peptide (ANP) release in humans and to examine potential mechanisms for this effect. Twenty patients requiring cardiac catheterization were randomized to receive either mannitol (15-g bolus followed by 15% infusion mixed in 75 mmol/L saline at 100 mL/h for 1 hour) or an equal volume of 75 mmol/L saline, intravenously (IV). All measurements were made at three time points: at baseline, at 10 minutes (after the bolus but before radiocontrast administration), and at 60 minutes (after completion of the study). Baseline plasma ANP (P ANP ) measurements (mean ± SE) were similar in both groups (saline, 73 ± 38 pg/mL; mannitol, 62 ± 11 pg/mL). P ANP increased significantly over time for the set of all patients (analysis of variance [ANOVA], P ANP increased significantly only in the group receiving mannitol (saline, 76 ± 43 pg/mL; mannitol, 100 ± 29 pg/mL) ( P OSM ), plasma antidiuretic hormone (P ADH ) levels, and right atrial and pulmonary wedge pressures increased significantly over time for the set of all patients (ANOVA, P ANP and the change in S OSM ( P r = 0.33). In conclusion, intravascular infusion of mannitol or radiocontrast increased P ANP levels. The mechanism may be multifactorial, with a potential role for an increase in S OSM and/or P ADH .
Primary amyloidosis of renal pelvis and renal cortical adenoma

A case of primary renal pelvic amyloidosis presenting with spontaneous extravasation is discussed. The association with an ipsilateral renal cortical adenoma is noted. A review of the pertinent literature is given.
Estimation models for molten slag and alloy viscosities

Viscosities of molten metals and slags play vital roles in many high-temperature phenomena that are important for advancing process control and product quality in molten-metal processing and casting. Because measuring viscosities of high-temperature melts is expensive, the need exists for reliable viscosity estimation methods based on the temperature and composition of the melt. This paper reviews some available models for alloys and slags, and examples are shown for melts of interest to both ferrous and non-ferrous processing
Institutional legitimacy and co-management of a marine protected area: implementation lessons from the case of Xcalak Reefs National Park, Mexico.

This paper is an exploration of the relationship between a conservation intervention and the quest for local institutional legitimacy and conservation success through co-management. More precisely, this paper will employ the case of Xcalak Reefs National Park (PNAX) to illuminate the interaction between contextual and procedural elements of co-management implementation, how these variables affect the production of legitimacy in the minds of local resource users, and how resultant attitudes can subvert both management devolution and resource conservation. The failure to produce co-management will be related to the mismatch inherent in attempts to map co-management onto a histories and institutions that do not align with the morality and practicalities necessary for its implementation. The case reiterates the necessity for conservation managers and practitioners to have an understanding of local history and context. Lastly, Xcalak demonstrates the dangers for the success of conservation and development prog...
Laser ablation of refractive micro-optic lenslet arrays

A CO2 laser is used to ablate concave lenslets in fused silica; these lenslets are then used to replicate or mold convex lenslets in plastic. The lenses range in size from 100 micrometers to 500 micrometers in diameter with speeds from f/1 to greater than f/10. The size and speed of the lenses can be controlled by changing the power, size, and exposure time of a focused CO2 laser beam. The ablation process is repeatable and lends itself easily to making large arrays of lenslets, limited in size only by the travel constraints of the mechanical stages that move the fused silica work piece. The entire process has been computerized so that an array of micro- optic lenses can be made accurately to any specification. Lenslets have been made in arrays of 1 X 10 to 60 X 60 with spacings of 300 micrometers to 2 mm between the centers of the lenslets.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Comparison of flow cytometry to routinetesticular biopsy in male infertility

Abstract We compared DNA flow cytometry to morphologic evaluation of routine testicularbiopsies as methods of monitoring spermatogenesis. The study group consisted of 14 azoospermic men and 5 others who underwent testicular surgery unassociated with fertility problems. The findings for both studies were divided into three groups: normal, moderately abnormal, and markedly abnormal. Correlations between the findings from routine biopsy and flow cytometry were good. Of 9 patients having normal testicular morphology, 7 had normal ploidy classes by DNA flow cytometry while 2 had moderately abnormal histograms. Of 5 cases with moderately abnormal morphology, 1 had normal, 1 had moderately abnormal, and 3 had markedly abnormal ploidy distributions. In 5 cases described as Sertoli cell only, all DNA histograms were markedly abnormal, consisting almost exclusively of diploid cells. DNA flow cytometry of testicular biopsies and aspirates has been demonstrated to be a rapid, reproducible, and objective approach in evaluating the infertile male and is a promising method to investigate spermatogenesis in an outpatient clinic in lieu of formal testis biopsy.
AAT Observations of the SL9 Fragment C, D, G, K, N, R, V, and W Impacts with Jupiter: Lightcurves and Imaging

We used the InfraRed Imaging Spectrometer (IRIS) on the Anglo-Australian Telescope to monitor the impacts of Comet Shoemaker-Levy 9 with Jupiter.
Characterization of d.c.jet CVD diamond films on molybdenum

Abstract Diamond films grown using a thermal plasma technique are characterized using a variety of techniques. The relationships between the chemistry, morphology, and mechanical properties are explored using microscopy, Raman spectroscopy, Auger electron spectroscopy, and X-ray photoelectron spectroscopy. The characteristics of films grown using two different nucleation enhancement techniques are shown. Films grown using high methane concentrations at the beginning of growth produce large grained columnar films, whereas films grown on substrates which have been treated with a diamond polishing step show nanocrystalline structures. Variations in sp3 and sp2 bonding and peak shifts are tracked through the thickness of the film, corresponding to variations in the methane concentration during growth. Stresses are measured using peak shifts and beam bending techniques. Adhesion is tested using indentations, and is shown to increase both as growth temperatures and surface roughness increase.
First and second order Raman scattering in GaP to 128 kbar

Abstract One- and two-phonon room temperature Raman spectra of GaP were measured to 128 kbar using a diamond-anvil pressure cell. Linear and quadratic pressure coefficients were determined for phonons at Γ, L, (X→K), and Σ. The results suggest possible “soft” mode behavior for TA(L) and TA(X→K) phonons.
A SHORT PROOF THAT COMPOSITE TWISTED UNKNOTS ARE SINGLY TWISTED UNKNOTS

We present a short proof of a theorem of Hayashi and Motegi and (independently) Goodman-Strauss that only singly twisted unknots are composite.
Studies of water uptake in the euryhaline crab, Rhithropanopeus harrisi

Water uptake in the crab, Rhithropanopeus harrisi, was studied using D2O (deuterium oxide) as a label. Results were expressed as per cent saturation, or the D2O concentration in the blood, attained in a 30-minute exposure to D2O at 20°C, expressed as a percentage of the D2O concentration in the bathing medium. Crabs acclimated to 75% sea water (SW), to which the blood is about isosmotic, had a mean per cent saturation of 51.8, and in 10% SW-acclimated crabs (blood hyperosmotic by about 40% SW) the mean per cent saturation was 33.9. Thus, water uptake, or exchange, is slower when the osmotic gradient favors net water uptake than when no osmotic gradient exists. In gill chamber perfusion experiments at least 87% of the total water influx in 10% SW and 92% of the total in 75% SW are taken up in the gill chambers, the gills probably being responsible for most, if not all, of the uptake. The time course of acclimation between 10% SW and 75% SW was followed in both directions. Measurable changes in water uptake occurred in 30 minutes; half the change from 75% SW to 10% SW occurred in two hours (seven hours for the transfer from 10% SW to 75% SW), and over 90% of full acclimation was reached in two days. Gill chamber perfusion experiments showed that the receptor or receptors which perceive the change between 10% and 75% SW and mediate the change in water uptake are not in the gill chamber. Thus the system responsible for the change in water uptake is composed of at least a receptor with some means of communication (presumably nervous or hormonal) with the effectors (probably the gills). The use of Na+-free and Cl−-free D2O media showed that the absence of these ions did not affect water uptake, and that the change in water uptake was not caused by a change in influx of these ions.
Retard system solution on electric mining trucks

Loss of dynamic brake is one of the important issues of AC electric mining trucks. The lack of dynamic brake reduces the safety and worries the truck driver. The driver may be forced to use the service brake, which increases the cost of repair and maintenance. Also, the service brake is designed for truck speeds less than 3–6 mph and is not proper for high speeds. The AC electric truck has retard contactors in series with grid resistors. When the driver presses the retard pedal to reduce the speed, the contactors are closed and power of traction motors are transferred to the inverter cabinet and then dissipated on grid resistances. Each contactor includes main contacts for its energy dissipative network. A set of auxiliary contacts that are used to control the main contacts provides feedback to a vehicle system control circuit. Auxiliary contacts can be subjected to dust, carbon monoxide and other contaminants which prevent the auxiliary contacts from operating properly. Improperly operating auxiliary contacts can result in a fault or a loss of retard braking for a short period of time. This paper describes the innovative design, implementation, and introduction of Unit Rigs' successful AC haul truck drive system without using auxiliary contacts on the main retard contactors.
Environmental tobacco smoke furthers progression of diabetic nephropathy.

Clinical studies suggest that smoking is a risk factor in the progression of chronic kidney disease, including diabetic nephropathy. The mechanisms involved are not completely understood. We have previously demonstrated that nicotine, one of the compounds present in large amounts in tobacco, promotes mesangial cell proliferation and fibronectin production. In this study, we hypothesized that exposure to environmental tobacco smoke (ETS) promotes the progression of diabetic nephropathy by increasing the expression of profibrotic cytokines such as transforming growth factor-beta (TGF-β) and the extracellular matrix proteins fibronectin and collagen IV. Six-week-old diabetic (db/db) mice were divided into 2 groups. The experimental group (n = 12) was exposed to ETS at a concentration of 30 mg/m3 for 6 hr/d, 5 d/wk for 8 weeks. The control group (n = 8) was exposed to room air. Urine was collected before euthanasia for albumin (enzyme- linked immunosorbent assay) and creatinine measurements (mass spectrometry). After euthanasia, the kidneys were harvested for morphometric analysis and Western blot analysis. Serum was saved for cotinine measurements by enzyme-linked immunosorbent assay. ETS exposure resulted in serum levels of cotinine similar to those found in human smokers. ETS exposure for 8 weeks induced significant mesangial expansion (approximately 50% increase) that was accompanied by concomitant increases in TGF-β and fibronectin expression (approximately 20%). However, ETS did not modify results in significant changes in urinary albumin excretion. These studies demonstrate that ETS exposure worsens the progression of diabetic nephropathy by increasing the amount of mesangial expansion and that these effects are likely mediated by increased expression of profibrotic cytokines such as TGF-β.
Transfer-matrix analysis of the canonical-cell model of a quasicrystal

Abstract Using a computational algorithm, we have calculated transfer matrices for the 2 1 , 3 2 , and 5 3 approximants to the quasi-periodic canonical-cell tiling. In the last case this algorithm leads directly to a new set of large cubic approximants. The transfer matrices also give us information about the entropy of ensembles of random tilings with periodic boundary conditions along two out of the three real-space axes. By introducing chemical potentials coupling to various properties of the members of this ensemble, we have calculated the variation of the entropy with the mean phason strain and volume of the tilings. The maximum of the entropy gives us the preferred values of the strain and volume, and the coefficients of its quadratic variation about this maximum give us the phason elasticity tensor, which is measurable in diffraction experiments.
Retroperitoneal mass presentations of B-immunoblastic sarcoma.

A clinicopathologic analysis of nine patients with B-immunoblastic sarcoma (B-IBS) presenting as a bulky lymph node-based retroperitoneal mass is reported. The histologic and immunologic findings, similar to those reported in B-IBS presenting in various other nodal and extranodal sites, support the recognition of this aggressive large cell non-Hodgkin's lymphoma (NHL) as a distinct pathologic entity. The patients, with a mean age of 60.5 years, presented for evaluation of abdominal pain and a palpable abdominal mass. Four patients were Stage II or IIE, one Stage III, and four Stage IV; eight of nine had B symptoms. Chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisone, bleomycin [CHOP-B] or cyclophosphamide, doxorubicin, vincristine, methotrexate with leucovorin rescue, cytarabine [ACOMLA]) yielded significant palliation in five patients (mean survival, 12.3 months); three untreated patients and one receiving radiation treatment (XRT) died within 1 month from diagnosis. There was a striking predilection for pleuropulmonary involvement in disseminating disease. The initial blood lymphocyte count correlated significantly with survival (correlation coefficient, 0.84). The one durable complete remission (CR) was obtained in a patient who received substantial surgical debulking before chemotherapy. Cancer 56: 1733-1741, 1985.
The Ontogeny of Pulmonary Defenses: Alveolar Macrophage Function in Neonatal and Juvenile Rhesus Monkeys

Using the technique of bronchoalveolar lavage, we isolated alveolar macrophages (AM) from the lower respiratory tract of newborn (1-4 days of age), infant (6-10 days of age), juvenile (3-6 months of age), and adult rhesus monkeys. The AM thus obtained were assayed in vitro to determine their chemotactic, phagocytic, and candidicidal capabilities. The predominant (greater than or equal to 89%) cell type in bronchoalveolar lavage effluent in all ages was the AM. Chemotaxis, phagocytosis, and killing of Candida albicans were markedly impaired in neonatal AM as compared with those from infants, juveniles, and adults. AM chemotactic activity achieved normal adult values by 6 days of age. Phagocytosis, and to a lesser extent candidicidal activity, were significantly improved in 6-day-old animals, but adult levels were still not achieved even by 6 months of age.
Respectable Vamp: A Black Feminist Analysis of Florence Mills’ Career in Early Vaudeville Theater

Florence Mills was one of only a few African American women vaudeville performers to become an international success. Born in Washington D.C. in 1895 and raised in Harlem, New York, Mills was a child performer in dramatic and musical theater. Through analysis of Florence Mills’ performances in Shuffle Along (1921), Dover Street to Dixie (1923) and The Black Birds Revue (1926), I seek to reveal the ways Florence Mills made use of the cultural economies of vaudeville to resist dominant constructions of race and gender. In particular, I assert that Florence Mills manipulated white American and European desires to consume slave culture, and expanded economic and cultural possibilities for African American women entertainers.
Failure of dobutamine to increase exercise capacity despite hemodynamic improvement in severe chronic heart failure

The acute hemodynamic and metabolic effects of dobutamine administered during exercise were studied in 8 patients with severe chronic heart failure. Exercise was performed on an upright bicycle ergometer using a graded protocol. During exercise performed without administration of dobutamine, exhaustion occurred after 4.5 ± 1.2 minutes of exercise. The cardiac index increased from 1.61 ± 0.25 to 2.67 ± 0.59 liters/min/m 2 (p 2 (p
TRANSLOCATION OF FOOD RESERVES FROM SOYBEAN COTYLEDONS AND THEIR INFLUENCE ON THE DEVELOPMENT OF THE PLANT.

contained in the cotyledons on subsequent growth of the plants. Many investigations have dealt with the transformations which occur in the reserve food materials in seeds of crop plants as germination proceeds. Few studies, however, have been concerned with the rate of transfer of these foods to the seedling. No reports have been found in the literature on how long the seedling is dependent on the reserves in the cotyledons for successful establishment and later development. This information was desired for use in mineral nutrition studies on soybeans particularly where the effects of limiting levels of some of the major nutrients are being investigated. At starvation levels of nutrition, it was felt that the amount of a particular element supplied by the cotyledons may be sufficient to influence experimental procedure. Using semiquantitative, microchemical methods on freezing microtome sections of Manchu soybean seeds, Von Ohlen (12) followed the translocation of organic and inorganic substances from the cotyledons to the seedling during germination in the dark. His results show that oil moved out of the cotyledons more rapidly than the other main organic reserve, protein, and that among the mineral elements, potassium was translocated at a greater rate than phosphorus or magnesium. Holman (7) found that the fat content of Agat(e) soybeans had decreased 78%, 17 days after planting. The work of Miller (10) on sunflower probably gives the most complete data on the transformation and movement of foods in oilseed plants. The seedling material analyzed was grown under greenhouse conditions with natural light but at emergence the seedlings were transferred to a carbon dioxide-free atmosphere so that the seedlings were dependent upon the reserves of the cotyledons throughout the growing period. Miller's data show that hydration of the cotyledons was complete in 10 days, dry weight decreased gradu
Home street home: The interpersonal dimensions of adolescent homelessness

This paper draws on the available literature, as well as unpublished data, to reconstruct the often chaotic early childhood experiences of homeless adolescents and to describe the problematic ways of relating that may result from these troubled life histories. We also examine the processes by which homeless youth become separated from their families, and we make connections between socio-emotional problems on the street and early neglect and abuse at home. The risk-amplification model is offered as a theoretically compelling explanation of the adolescent homeless experience, high rates of victimization on the streets, and mental health problems that arise out of these circumstances. Finally, we present a promising approach for intervening with homeless youth, one that explicitly targets this cycle of ineffective interpersonal relationships.
Asymptotic coefficients for one-interacting-level Voigt profiles

Abstract In previous work, we have determined the asymptotic behavior of general Voigt profiles with general width and shift functions. The resulting asymptotic coefficients are functions of the perturber/radiator mass ratio; also, the coefficients for the one-interacting-level (OIL) profiles proposed by Ward et al. were studied. In this paper, the behavior of the OIL asymptotic coefficients for large mass ratio values is determined, thereby providing a complete picture of OIL asymptotics for all mass ratios.
Two unique patients with novel microdeletions in 4p16.3 that exclude the WHS critical regions: Implications for critical region designation

Wolf-Hirschhorn syndrome (WHS) is characterized by growth delay, developmental delay, hypotonia, seizures, feeding difficulties, and characteristic facial features. Deletion of either of two critical regions (WHSCR and WHSCR-2) within chromosome band 4p16.3 has been proposed as necessary for the minimal clinical manifestations of WHS and controversy remains regarding their designation. We describe two patients with novel terminal microdeletions in 4p16.3 who lack the characteristic facial features but do show some of the more nonspecific manifestations of WHS. The first patient had a ring chromosome 4 with an intact 4q subtelomere and a terminal 4p microdeletion of approximately 1.27-1.46 Mb. This deletion was distal to both proposed critical regions. The second patient had a normal karyotype with a terminal 4p microdeletion of approximately 1.78 Mb. This deletion was distal to WHSCR and the breakpoint was near or within the known distal boundary for WHSCR-2. Both patients showed significant postnatal growth delay, mild developmental delays and feeding difficulties. Their facial features were not typical for WHS. The phenotype of the first patient may have been influenced by the presence of a ring chromosome. Seizures were absent in the first patient whereas the second patient had a complex seizure disorder. Characterization of these patients supports the hypothesis that a gene in WHSCR-2, LETM1, plays a direct role in seizure development, and demonstrates that components of the WHS phenotype can be seen with deletions distal to the known boundaries of the two proposed critical regions. These patients also emphasize the difficulty of mapping clinical manifestations common to many aneusomy syndromes.
Cell lineage and differentiation on the male foreleg of Drosophila melanogaster.

Abstract Cell lineage was studied in the epidermis of the basitarsus of the foreleg of male Drosophila melanogaster . This was accomplished by “marking” single cells, and their descendants, with genotypes different from the rest of the tissues. The mosaic basitarsi thus produced had areas with yellow chaetae on a background of black chaetae. On the basis of cell lineage data, the male basitarsus can be divided in two main parts. Region A occupies most of the segment including the primary sex comb and the central bristle. It does not include the area of the longitudinal rows 1, 2, and 3 and that of the secondary sex comb which shows a close developmental relation to rows 1 and 2. These areas constitute region B. Within region A cell lineage data yield a subdivision into A-1 which includes longitudinal row 1′, the transverse rows, longitudinal rows 7 and 6 and 5.5, the primary sex comb and the central bristle; and A-2 the remaining area which includes longitudinal rows 4 and 5. In region A-1 the following developmental relations were found. (a) The descendants of a yellow cell tend to form longitudinal strips of tissue both along the longitudinal rows and in the area of the transverse rows. (b) The proximal teeth of the sex comb and the central bristle are closely related to the posterior part of the transverse rows. (c) The middle teeth are closely related to the middle and the anterior parts of the transverse rows and to row 7. (d) The bractless bristles 5.5 are closely related to the distal teeth within the middle part of the sex comb. (e) The distal teeth of the sex comb are closely related to longitudinal row 6, and less closely, to row 7. The data suggest that the prospective area of the primary sex comb initially occupies the same distal part of the basitarsus as the most distal transverse rows of the female basitarsus. They suggest further that in the male the tissue of this area shifts anteriorly, whereby it changes its direction by approximately 90 degrees. This not only is deduced from the results of the cell lineage studies, but explains the position of the bracts at the base of the sex comb teeth and the direction assumed by the teeth, both of which deviate by about 90 degrees from that of the other chaetae of the segment. The above results on pure male basitarsi were confirmed by cell lineage studies of gynandric basitarsi. Systematic deviations from the norm in the location and direction of the male sex comb teeth and of female chaetae at the distal part of the segment are the result of the differential morphogenesis of the male and female tissues in this area.
Discretization of cascaded continuous-time controllers and uncertain systems

This paper presents a new method for the digital modeling of a continuous-time uncertain system and a new method for the digital redesign of a sampled-data uncertain system. The system matrices characterizing the state-space representation of the original uncertain system are assumed to be interval matrices. The Chebyshev quadrature formula together with the interval arithmetic are used for the digital interval modeling, and a dual concept of digital interval modeling is utilized to discretize a predesigned cascaded analog controller for robust digital control of a continuous-time uncertain system. Using the newly developed digital interval models and digitally redesigned controllers, the resulting dynamic states of the digitally controlled sampled-data uncertain systemsare able to closely match those of the originally analogously controlled continuous-time uncertain systems for a relatively longer sampling period.
Towards an alternative logic of technological change: Insights from Corn Belt agriculture

Abstract Empirical evidence drawn from a Corn Belt case study is used to connect the environmental and socioeconomic contradictions of agricultural production in the region. The paper rests on several key arguments: First, a preliminary case is made for a more explicit recognition of the theoretical and empirical links between the socioeconomic problems of agricultural regions stemming from chronically low levels of producer surplus retention and similar problems of social welfare associated with reduced levels of remunerated labor in the industrial sector. Second, there is a parallel need for connecting the negative social and environmental costs of capitalist agriculture. The case study uses the evolving production process on individual farms as a means of exploring the causal relationship between the movement towards capitalist social relations and environmental degradation resulting from intensive patterns of synthetic chemical use. And third, the role of agency among family farmers faced with a regional economic crisis emerges from the case study analysis. In the 1980s, a small minority of Iowa farmers would adopt, perfect and disseminate a low-chemical input system of production attuned to the logic of family farm social relations. The contribution of the state-sponsored research institutions was notably absent. The case example highlights the process of technological change as a socially-constructed phenomenon subject to alternative forms of rationality that emerge from different syntheses of ecological conditions and social relations.
Effects of Soil Physical Nonuniformity on Chamber-Based Gas Flux Estimates

Chamber methods for measuring trace gas fluxes are prone to errors resulting in large part from the alteration of near-surface concentration gradients. There is little information available, however, for quantifying these errors or determining how they vary with soil physical properties, chamber deployment methods, and flux calculation schemes. This study used numerical modeling to examine how these factors influence flux estimate errors in physically uniform and nonuniform soil profiles. Errors varied widely among profiles and flux calculation techniques. Soil profiles having identical predeployment fluxes but differing in water content and bulk density generated substantially different flux chamber data. A theoretical flux model that assumes physical uniformity performed relatively well in nonuniform soils but still generated substantial errors. For all flux models, errors were minimized with larger effective chamber heights (h) and shorter deployment times (DT). In light of these findings, recent studies that recommend minimizing h and extending DT to enhance nonlinearity of chamber data need to be reevaluated. It was also determined that random measurement error can result in skewed flux-estimate errors. Selection of chamber and flux calculation methods should consider the physical characteristics of the soil profile as well as measurement error. The techniques presented here can be used to develop soil- and method-specific error estimates.
Cellular localization of somatomedin (insulin-like growth factor) messenger RNA in the human fetus

The somatomedins or insulin-like growth factors (IGFs) are synthesized in many organs and tissues, but the specific cells that synthesize them in vivo have not been defined. By in situ hybridization histochemistry, IGF I (somatomedin C) and IGF II messenger RNAs were localized to connective tissues or cells of mesenchymal origin in 14 organs and tissues from human fetuses. IGF messenger RNAs were localized to perisinusoidal cells of liver, to perichondrium of cartilage, to sclera of eye, and to connective tissue layers, sheaths, septa, and capsules of each organ and tissue. All of the hybridizing regions are comprised predominantly of fibroblasts or other cells of mesenchymal origin. Because these cells are widely distributed and anatomically integrated into tissues and organs, they are ideally located for production of IGFs, which may exert paracrine effects on nearby target cells.
Lateral geniculate spikes in sleeping, awake, and reserpine-treated cats: Correlated excitability changes in superior colliculus and related structures

Abstract Spiking activity in lateral geniculate nucleus (LGN) may be recorded from cats during fast-wave sleep, with awake eye movements and following drug administration. The present experiments were undertaken to analyze visual system excitability changes correlated with these LGN spikes in fast-wave sleep, and to test whether comparable changes occur correlated with the LGN spikes in other conditions. Cats bearing chronically implanted electrodes were used to study the excitability of superior colliculus and related structures as a function of time during and following LGN spikes recorded under three conditions: fast-wave sleep; following reserpine administration; and with awake eye movements. Under these conditions, postsynaptic potentials in superior colliculus, cerebellum, pontine reticular formation, and visual cortex increased in amplitude throughout a 300-msec period beginning with the LGN spike. Eye movements elicited by optic nerve stimulation increased in amplitude along with postsynaptic potentials. Changes in response amplitude in all structures investigated were similar in the reserpinetreated and awake eye movement conditions to those of fast-wave sleep. This indicates that similar neuronal activity is associated with the LGN spikes of these three states. LGN spikes appear to signify neither a blanking circuit nor a corollary discharge, but rather are related to phasic activity in the midbrain reticular formation.
Acetone Metabolism in Normal and Ketotic Cows

Abstract Acetone-2-C 14 was injected intravenously into two spontaneously ketotic cows and one cow fasted for five days, and into all three cows when lactating normally. Peaks in specific activity of respired CO 2 and plasma glucose occurred 2 hr later. The standardized specific activity was higher in lactose than in casein or milk fat in all cows, for both the normal and ketotic states. Although the pattern of distribution of C 14 among the various products was the same in normal and ketotic cows, the over-all recovery of C 14 was only about one-tenth as great in ketotic cows as in normal cows. The data are consistent with acetone metabolism being predominantly glucogenic but quantitatively unimportant in both normal and ketotic cows.
Charge Exchange in Proton-Hydrogen-Atom Collisions

The charge-exchange cross sections for the reactions $p+\mathrm{H}\ensuremath{\rightarrow}\mathrm{H}+p$, and ${{\mathrm{H}}_{2}}^{+}+\mathrm{H}\ensuremath{\rightarrow}{\mathrm{H}}_{2}+p$ have been examined over the energy range 200 to 14 000 ev. In the experiment a dc fast-ion beam crossed a slow atomic hydrogen beam which was chopped at 100 cps. The desired signal thus was separable from the much larger signal arising from interaction of the ions with the residual gas in the vacuum chamber, because the signal arising from the interaction of the two beams occurred at the chopping frequency and in a specified phase. The signals used were the saturated slow-ion currents, recorded at a detector which did not discriminate the ion mass, and the slow-ion currents after mass analysis. The measured values at high energies agree very satisfactorily with the Born approximation calculations by Bates and Dalgarno and, at low energies, with calculations by Dalgarno and Yadav using the method of perturbed stationary states. Experimental comparison of cross sections for proton and deuteron collisions is presented.
The Interpretation of Repeat Positive Results for Gonorrhea and Chlamydia in Children

Abstract Background The diagnosis of gonorrhea and/or chlamydia in a prepubertal child beyond the neonatal period is confirmatory of mucosal contact with infective bodily secretions and therefore highly concerning for sexual abuse. When such a diagnosis is made, a report to protective authorities is warranted so that safety and potential criminal activity may be evaluated concurrent with the medical management. Occasionally, despite perceived adequate medical management and protective safety plans, a child may present with a repeat positive result for sexually transmitted infections. In this scenario, it is important for medical providers to carefully consider and be aware of the possible reasons for the repeat positive result: (1) treatment failure, (2) a new infection from repeated abuse, or (3) a false-positive result due to the limitations of nonculture testing. Case Prepubertal sisters were diagnosed with gonorrhea and Chlamydia and treated with antibiotics, and the individual identified as having sexually abused them was removed from the home. Summary and Conclusion Over a 4-month period, both children continued to have positive testing for chlamydia via the nucleic acid amplification test and/or culture. Concurrent with using alternate antibiotic treatment options, protective authorities were alerted to the fact that this was likely a reinfection. The investigative team later determined that a second adult, who tested positive for gonorrhea and chlamydia, was also sexually abusing both girls. Disclosures of abuse regarding both adult individuals were deemed credible by authorities and supported with collateral information.