cssi/SciSciGPT-SciSciNet huggingface dataset:
Disruption of desmosome assembly by monovalent human pemphigus vulgaris monoclonal antibodies

The intercellular interactions of the desmosomal cadherins, desmoglein and desmocollin, are required for epidermal cell adhesion. Pemphigus vulgaris (PV) is a potentially fatal autoimmune blistering disease characterized by autoantibodies against desmoglein (Dsg) 3. During calcium-induced desmosome assembly, treatment of primary human keratinocytes with pathogenic monovalent anti-Dsg3 mAbs produced from a PV patient causes a decrease of Dsg3 and desmoplakin but not desmocollin (Dsc) 3 in the Triton-insoluble fraction of cell lysates within 2 hours. Immunofluorescence and antibody ELISA studies suggest that pathogenic mAbs cause internalization of cell-surface Dsg3 but not Dsc3 through early endosomes. Electron microscopy demonstrated a lack of well-formed desmosomes in keratinocytes treated with pathogenic compared to nonpathogenic mAbs. In contrast, pathogenic mAbs caused late depletion of Dsg3 from preformed desmosomes at 24 hours, with effects on multiple desmosomal proteins including Dsc3 and plakoglobin. Together, these studies indicate that pathogenic PV mAbs specifically cause internalization of newly synthesized Dsg3 during desmosome assembly, correlating with their pathogenic activity. Monovalent human PV anti-Dsg mAbs reproduce the effects of polyclonal PV IgG on Dsg3 and will facilitate future studies to further dissect the cellular mechanisms for the loss of cell adhesion in pemphigus.
Ganglioside GM3 Inhibits Matrix Metalloproteinase-9 Activation and Disrupts Its Association with Integrin

Gangliosides GM3 and GT1b both inhibit epithelial cell adhesion and migration on fibronectin. GT1b binds to integrin α5β1 and blocks the integrin-fibronectin interaction; GM3 does not interact with integrin, and its effect is poorly understood. We evaluated the effects of endogenous modulation of GM3 expression on epithelial cell motility on several matrices and the mechanism of these effects. Endogenous accumulation of GM3 decreased cell migration on fibronectin, types I, IV, and VII collagen matrices; depletion of GM3 dramatically increased cell migration, regardless of matrix. GM3 overexpression and depletion in vitro correlated inversely with the expression and activity of matrix metalloproteinase-9; consistently, the cell migration stimulated by GM3 depletion is reversed by inhibition of matrix metalloproteinase-9 activity. Accumulation and depletion of GM3 in epithelial cells grown on fibronectin also correlated inversely with epidermal growth factor receptor and mitogen activated protein kinase phosphorylation and with Jun expression. Ganglioside depletion facilitated the co-immunoprecipitation of matrix metal-loproteinase-9 and integrin α5β1, while endogenous accumulation of GM3, but not GT1b, blocked the co-immunoprecipitation. These data suggest modulation of epidermal growth factor receptor signaling and dissociation of integrin/matrix metalloproteinase-9 as mechanisms for the GM3-induced effects on matrix metalloproteinase-9 function.
Electric-Circuit Burning-Clear and Damage Phenomena on Aircraft Structures

Normal and continuous performance of electric circuits is a prerequisite to the effective use of airplanes. Electric short circuits which result in the loss of power for vital control operations or which cause fires are definite hazards. The extensive use of the 28.5-volt d-c aircraft systems, the proposed 120-volt d-c system, and the consideration being given a three-phase 120-208-volt a-c grounded neutral system for high-altitude planes necessitated an investigation into the burning-clear and damage phenomena on all circuits. Short circuits were applied on an aluminum-alloy section of an airplane, and oscillograms of short-circuit current and voltage taken. In both the a-c and d-c systems it was found that the fault-damage and burning-clear phenomena depended upon the energy level in the short-circuit area. When the contact area between the conductor and aircraft structure was small, the energy level was high, and the fault burned itself clear. In such cases the aircraft structure was perforated. Increase in contact area and a consequent reduction in energy concentration resulted in a sustained fault current. In some of these cases a definite welding of the conductor to the aircraft structure occurred, while in others no burning took place.
For-profit versus non-profit freestanding psychiatric inpatient facilities: An update

Although several studies have examined the trend toward the decreasing differentiation of non-profit from for-profit general hospitals, few have focused on freestanding psychiatric hospitals. This study updates previous research that used psychiatric hospital data from calendar year 1986 with data from 1990. In addition, a preliminary examination of the influence of market competition on the behavior of non-profit psychiatric facilities was conducted. Results confirm a converging trend between for-profit and non-profit facilities that is related, in part, to competition.
Leader self-structure: A framework for positive leadership

We expand the conceptualization of positive leadership and hypothesize that leaders' ability to influence followers across varied complex situations will be enhanced through the development of a rich and multifaceted self-construct. Utilizing self-complexity theory and other aspects of research on self-representation, we show how the structure and structural dynamics of leaders' self-constructs are linked to their varied role demands by calling forth cognitions, affects, goals and values, expectancies, and self-regulatory plans that enhance performance. Through this process, a leader is able to bring the “right stuff” (the appropriate ensemble of attributes) to bear on and succeed in the multiple challenges of leadership. We suggest future research to develop dimensional typologies related to leadership-relevant aspects of the self and also to link individual positive self-complexity to more aggregate positive organizational processes. Copyright © 2009 John Wiley & Sons, Ltd.
Attenuation by catecholamine antagonists of the hypothermia that follows cerebral infraction in gerbils

Abstract The hypothermia that follows induction of cerebral infraction in gerbils can be attenuated by drugs which reduce the interactions between endogenous brain catecholamines and postsynaptic receptors. This observation is compatible with the hypothesis that stroke-induced hypothermia is mediated, in part, by the release of catecholamines from ischemic neurons.
Target-assisted iterative screening reveals novel interactors for PSD95, Nedd4, Src, Abl and Crk proteins.

Abstract A new in vitro screening method has been developed and applied to commercial phage-dis- played cDNA library to search for novel protein-protein interactions. PDZ, WW and SH3 domains from PSD95, Nedd4, Src, Abl and Crk proteins were used as targets. 12 novel putative and 2 previously reported interactions were identified in test screens. The novel screening format, dubbed TAIS (target-assisted iterative screening), is discussed as an alternative platform to existing technologies for pair-wise characterization of protein-protein interactions.
Global bifurcation of periodic solutions in nonlinear evolution problems with periodic forcing

Abstract This paper discusses the global bifurcation of 2 π -periodic solutions of u t = P ( λ , x , ∂ ) u + f ( λ , t , u ) with a homogeneous Dirichlet boundary condition, where P ( λ , x , ∂ ) is linear elliptic and the nonlinearity f is 2 π -periodic in t . The main differences from existing theories devoted to this type of problem can roughly be summarized as follows: (i) the bifurcation analysis makes no use of evolution operators or related concepts (Poincare maps, Floquet multipliers, etc.); (ii) the bifurcation/nonbifurcation points are characterized through an associated stationary problem; (iii) the functional setting allows for nonlinearities f exhibiting time discontinuities. Among other things, the results include various partial generalizations of the “bifurcation from the principal eigenvalue” theorem, which, unlike the classical version, do not require linear parameter dependence.
Glucose metabolism and hemoglobin reactivity in human red blood cells exposed to the tryptophan metabolites 3-hydroxyanthranilate, quinolinate and picolinate.

Abstract Glucose metabolism and hemoglobin reactivity in intact human erythrocytes were assessed in the presence of the tryptophan metabolites, 3-hydroxyanthranilate (3-HAT), quinolinate and picolinate. Of these compounds, only 3-HAT altered red cell oxidative status by inducing, in a dose-dependent manner, formation of methemoglobin and non-functional oxidation products of hemoglobin, and by increasing both net glycolytic flux and flux through the hexose monophosphate shunt. 3-HAT also decreased the normal lactate to pyruvate production ratio with pyruvate accumulating at the expense of lactate. These findings are consistent with the auto-oxidative reactivity of quinolinate, picolinate, and 3-HAT in that only 3-HAT undergoes base-catalyzed auto-oxidation (Dykens et al., Biochem Pharmacol 36 : 211-217, 1987). Lactate and pyruvate added to the medium in physiologic concentrations uncoupled oxidative glycolysis from reductive glycolysis, resulting in accumulation of pyruvate in the presence of 3-HAT with little increase in total glycolytic flux. Superoxide dismutase (SOD), which accelerates 3-HAT auto-oxidation in vitro (Dykens et al., Biochem Pharmacol 36 : 211–217, 1987), exacerbated HAT-mediated oxidative insult by increasing methemoglobin formation, hexose monophosphate shunt flux, and pyruvate accumulation. Persistence of 3-HAT-induced red cell metabolic responses and oxidative damage in the presence of SOD, DETAPAC (diethylenetriaminepentaacetic acid) and formate suggests that an organic-based radical, perhaps the anthranilyl radical produced during 3-HAT auto-oxidation, is the proximate agent exerting oxidative stress. Slow rates of auto-oxidation indicate that 3-HAT may be useful as a probe of antioxidant mechanisms in normal and diseased red blood cells.
Opioid receptor binding in rat spinal cord.

The interaction of various radioligands with spinal opioid receptors has been characterized under variable experimental conditions. Binding to μ, δ, and κ sites was measured in all (cervical, thoracic, lumbar) segments. The apparent affinity constant (K) of [3H]Ethylketocyclazocine (EKC) was similar in Tris, 2.09 (±1.06)×108 M−1, and phosphate buffer, 2.16 (±0.02)×108 M−1, when its interaction with δ and μ sites was blocked. Without blocking ligands, EKC binding was resolved in two components:K1=1.01 (±0.21)×109 M−1 andK2=0.95 (±0.61)×107 M−1. Likewise, the binding of [D-Ala2, MePhe4, Gly(ol)5]enkephalin (DAGO) or [D-Ala2, D-Leu5]-enkephalin (DADLE) alone was represented by a 2-site model. By adjusting the radioligand and receptor concentration or by the addition of blocking ligands, binding was represented by a 1-site model for DAGO,K=4.35 (±1.41)×108 M−1, and DADLE,K=2.44 (±0.08)×108 M−1.
Quantifying Vaginal Motion Associated With Daily Endorectal Balloon During Whole Pelvis Radiation Therapy for Gynecologic Cancers

30-60% of patients. Even 1 cm of PTV margin was inadequate in 20-30% of patients. The only beneficial effect of knee and feet support was found to reduce V45 and V50 doses of rectum and bladder. Conclusions: PTV margin of 15 mm in superior-inferior and posterioranterior, and 5 mm in lateral directions for CTV primary were found to be adequate in gynecological cancer patients. A minimum of 7 mm margin should be given to iliac CTV. The striking shifting in presacral CTV was believed to be due to the unforeseen malposition of the hip positions of obese patients. Author Disclosure: M. Gultekin: None. C. Yilmaz: None. G. Eren: None. F. Yildiz: None.
Modal analysis of transport processes in SPRITE detectors

Carrier transport in signal-processing-in-the-element (SPRITE) detectors is an important phenomenon because it determines properties such as the responsivity and the modulation transfer function (MTF). The previous literature has presented approximate solutions to the transport problem that neglect boundary effects, which have long been thought to play a major role in SPRITE behavior. We present a new solution to the problem through the use of modal analysis. This method intrinsically includes boundary conditions and thus is more complete than the previous analysis. Furthermore we use this solution to derive expressions for the MTF. The effects of the boundary conditions on the MTF are studied to determine their optimum values.
THERAPEUTIC USE OF THE SEX STEROLS IN FUNCTIONAL MENO METRORRHAGIA1

FUNCTIONAL irregularities of uterine bleeding are due in the final analysis to disturbances in the physiologic reciprocities of the ovaries and uterus. The exciting factors may be intrinsic in these or may be extrinsic endocrine or non endocrine ones. Rational therapeutic endeavors should be directed at the level of the primary alterations. As a rule treatment which employs surgery, radium or roentgen rays is an admissionof thedefeat of specific endocrine therapy. In view of the controversial nature of certain observations permitted from the data tobe submitted, some consideration of the etiology of functional bleeding seems justified. A certain group of patients, identified with comparative ease, com prises those in whom bleeding is only one of the symptoms and signs of obvious endocrine disease. Other groupings are apparent in which significant etiologic cor relates include gynecologic, nutritional, metabolic, hematologic, constitutional and other factors.
Consequences of metolachlor induced inhibition of gibberellin biosynthesis in sorghum seedlings

Abstract Forage sorghum [Sorghum bicolor (L.) Moench] cultivars were field evaluated for response to seed protectants CGA 92194, CGA 133205, and flurazole for ability to reverse the activity of metolachlor (2.8 kg a.i./ha) and alachlor (3.36 kg a.i./ha). Funk “G102F” was “tolerant” to metolachlor and alachlor (∼17% decrease in forage production), R. C. Young “Red Top Kandy” was “intermediate” (37–50% inhibition), and AgraTech “GK 83S” was “susceptible” (60–65% inhibition). Average plant heights were decreased 0, 26, and 32% for “G102F,” “Red Top Kandy,” and “GK 83S,” respectively, while numbers of plants/4.57-m row were decreased 19, 70, and 90%, respectively. Resultant average individual plant fresh weights (g/plant) were 104, 200, and 410% of the untreated plants for G102F, Red Top Kandy, and GK 83S, respectively. Thus, metolachlor and alachlor lethal responses were exhibited at a very early stage of sorghum seedling development (
Structural models for (Na2O)x(SiO2)1 − x glasses with periodic boundaries**

Structural models of (Na2O)x(SiO2)1 − x glasses for x = 0, 0.018, 0.111, 0.222, and 0.333 with periodic boundary conditions are constructed. The model structures are computer-relaxed using a combination of Keating-type potential and Lennard-Jones potentials. The structural characteristics and the radial distribution functions of these models are shown to agree well with experimental data and results of other theoretical models.
RNA helicase dynamics in pre‐mRNA splicing

The DExH‐box NTPase/helicase Prp22p plays two important roles in pre‐mRNA splicing. It promotes the second transesterification reaction and then catalyzes the ATP‐dependent release of mature mRNA from the spliceosome. Evidence that helicase activity is important emerged from the analysis of Prp22p motif III (SAT) mutations that uncouple the NTPase and helicase activities. We find that S635A and T637A hydrolyse ATP, but are defective in unwinding duplex RNA and releasing mRNA from the spliceosome. The S635A mutation is lethal in vivo at ≤30°C and results in slow growth at 34–37°C. Further insights into helicase action during splicing were gleaned by isolating and characterizing intragenic suppressors of prp22‐S635A. Biochemical analysis of the S27 suppressor protein showed that a second mutation of Val539 to Ile in motif Ia revived the helicase activity of the S635A mutant together with the ability to catalyze mRNA release. These findings underscore the tight correlation of RNA unwinding and spliceosome disassembly and demonstrate how suppressor analysis can be used to dissect the subtle internal domain dynamics of helicase action.
Mappability and read length

Power-law distributions are the main functional form for the distribution of repeat size and repeat copy number in the human genome. When the genome is broken into fragments for sequencing, the limited size of fragments and reads may prevent an unique alignment of repeat sequences to the reference sequence. Repeats in the human genome can be as long as $10^4$ bases, or $10^5-10^6$ bases when allowing for mismatches between repeat units. Sequence reads from these regions are therefore unmappable when the read length is in the range of $10^3$ bases. With the read length of exactly 1000 bases, slightly more than 1% of the assembled genome, and slightly less than 1% of the 1kb reads, are unmappable, excluding the unassembled portion of the human genome (8% in GRCh37). The slow decay (long tail) of the power-law function implies a diminishing return in converting unmappable regions/reads to become mappable with the increase of the read length, with the understanding that increasing read length will always move towards the direction of 100% mappability.
Testosterone Supplementation Therapy in the Treatment of Patients with Metabolic Syndrome

Metabolic syndrome (MetS) comprises a clinical complex of patient risk factors, including increased waist circumference, high triglyceride levels, low high-density lipoprotein cholesterol level, high blood pressure, and insulin resistance, the presence of which increases the likelihood of developing diabetes and cardiovascular disease. With a quarter of the American adult population affected, MetS and type 2 diabetes mellitus have been referred to as the most significant public health threats of the 21st century. Lifestyle modification and weight loss are recommended, however, no specific pharmacologic treatment is known. Given that low levels of testosterone have been implicated in the pathogenesis of MetS and an inverse relationship exists between circulating testosterone levels and the development of MetS, it is tempting to speculate that men with MetS may benefit from testosterone supplementation therapy. As such, our review examines the role of testosterone and the use of testosterone supplementation therapy as a treatment in men with MetS.
Problems and prospects in the analysis of epitaxial growth of the wide bandgap Group-III nitrides

Abstract A review of the experimental situation in molecular-beam epitaxial growth of GaN is given in the framework of three problem areas that may be susceptible to computational methods: relaxation of strain in large mismatch systems, growth-surface kinetics of plasma-excited nitrogen, and surfactant-mediated epitaxy. Basic properties of acceptor-doped GaN are discussed and then the importance of these three problem areas is made clear via examination of recent experimental results.
Predicting PTSD Prospectively Based on Prior Trauma History and Immediate Biological Responses

Studies examining the biopsychology of posttraumatic stress disorder (PTSD) have suggested that PTSD is characterized by alterations of the primary stress pathways: the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). More recent investigations point to the presence of these alterations soon after a traumatic event, leading researchers to suggest that acute biological responses may serve as risk or resilience factors for the development of PTSD. The present article reviews the evidence for early biological predictors of PTSD, with a focus on the role of prior trauma as a contributor to both hormonal abnormalities and increased risk for the development of PTSD following a subsequent trauma.
Muscle cell cultures from chicken breast muscle have increased specific activities of creatine kinase when incubated at 41 °C compared with 37 °C

Chicken muscle cell cultures were incubated at 41 degrees C, the physiological chicken body temperature, and compared with cultures incubated at 37 degrees C, the typical cell culture incubation temperature. The cultures incubated at 41 degrees C show not only an increase in creatine kinase (CK)-specific activity but also a marked increase in the percentage of adult muscle CK isozyme (MM-CK) in 7-day muscle cultures. Muscle cell cultures incubated in the presence of cytosine arabinoside (ara-C), a cell proliferation inhibitor, do not have the mononucleated cell overgrowth seen at 41 degrees C and thus exhibit a further increase in creatine kinase-specific activity compared with cultures incubated at 41 degrees C in the absence of ara-C. These results suggest that muscle cell cultures incubated at 41 degrees C are more highly differentiated than those incubated at 37 degrees C.
Cosmetic Lower Lid Blepharoplasty

This article will review the topic of cosmetic lower lid blepharoplasty including: preoperative patient evaluation and selection; blepharoplasty surgery; postoperative patient care; and complications of surgery. The emphasis of this article is surgical techniques, including standard lower lid blepharoplasty via a subciliary skin incision, lower lid blepharoplasty combined with lateral canthal lower lid tightening procedures, and the transconjunctival lower lid blepharoplasty procedure. Preoperative and postoperative surgical results are presented.
Protection of renal tubular cells against the cytotoxicity of cadmium by glycine.

Abstract Glycine treatment is reported to protect against the nephrotoxicity of cadmium (Cd) in rats. The purpose of the present study was to explore the mechanism of this protection using a renal epithelial cell line, LLC-PK 1 . The cells were incubated with 10–30 μM Cd in serum-free DMEM and cytotoxicity was evaluated by LDH leakage into the incubation medium. Under these conditions, 20 and 30 μM Cd concentrations were cytotoxic. As compared to the non-Cd-exposed cells, the LDH release was elevated more than six-fold in cells exposed to 30 μM Cd for 24 h. Co-treatment with 5–50 mM glycine was cytoprotective in a concentration-dependent manner. Prior treatment with 50 mM glycine for 16 h, or co-treatment for 24 h, reduced LDH leakage due to 30 μM Cd exposure by 60 and 66%, respectively. Co-incubation with 50 mM alanine was also protective but only about half as effective as with glycine. During the first 4 h, prior to the onset of any significant cell membrane damage, the Cd-exposed cells accumulated 0.55 μg Cd/mg protein. Glycine pre-treatment or co-treatment reduced Cd accumulation by about one-quarter or one-half, respectively. To delineate the mechanism of glycine's effect on Cd accumulation, the efflux of Cd was studied after a 30 min pulse exposure. The results suggested that pre-treatment reduced Cd accumulation by increasing its efflux from the cells. In contrast, co-treatment reduced Cd efflux, suggesting that the co-treatment lowered Cd accumulation by suppressing its uptake. When co-incubated, Cd and glycine formed a complex that was apparently responsible for the marked reduction in Cd uptake. It is concluded that, regardless of the mode of treatment, glycine is cytoprotective against Cd and that it may do so by lowering the intracellular Cd burden.
The Blood-Testis and Blood-Epididymis Barriers Are More Than Just Their Tight Junctions

The terms blood-testis barrier (BTB) or blood-epididymis barrier (BEB), are often described as Sertoli cell-Sertoli cell tight junctions (TJs) or TJs between the epithelial cells in the epididymis, respectively. However, in reality, the BTB and BEB are much more complex than just the TJ. The focus of this minireview is to remind readers that the complete BTB and BEB are comprised of three components: anatomical, physiological, and immunological. The TJs form the anatomical (physical) barrier that restricts passage of molecules and cells from entering or exiting the lumen. The physiological barrier is comprised of transporters that regulate movement of substances in or out of the lumen, thus creating a microenvironment, which is critical for the proper development and maturation of germ cells. The immunological barrier limits access by the immune system and sequesters the majority of the autoantigenic germ cells. Combined with the overall immune-privilege of the testis, this suppresses detrimental immune responses against the autoantigenic germ cells. These three components on their own do not create a complete functional barrier; instead, it is the interaction between all three components that create a barrier of maximal competence.
Transconductance degradation in VLSI devices

Abstract Experimental results from small geometry VLSI devices show that as devices are scaled, transconductance degradation occurs. This results from scaling either the length or width. A model using a mobility expression developed by Wang is used to predict transconductance in small MOS devices. Comparison between theory and experiments is excellent.
The swimming of spermatozoa in an active channel.

Abstract Sperm transport in the human cervix is a vital step in the process of fertilization, and the roles of the cervix and the cervical mucus have been extensively discussed and investigated. A mechanism to explain sperm transport through the cervical mucus based on a dynamic interaction between the cervical mucus and the swimming sperm has been suggested by Odeblad. A mathematical model of Odeblad's proposed mechanism of sperm transport in the cervix is presented which idealizes the geometry as a self-propelling infinite sheet in a two-dimensional channel. The sheet propels itself by propagating waves of lateral displacement. The channel walls are allowed to vibrate as proposed by Odeblad as right traveling waves, left traveling waves or standing waves. The propulsive velocity and energy expended by the sheet and flow rates in the channel are computed. These results are presented and conclusions are given concerning the effect of wall oscillations on self propelling sheets. The conclusions of Odeblad's theory are contrasted with the results of the model.
Cullin 4A-mediated Proteolysis of DDB2 Protein at DNA Damage Sites Regulates in Vivo Lesion Recognition by XPC

Xeroderma pigmentosum (XP) complementation group E gene product, damaged DNA-binding protein 2 (DDB2), is a subunit of the DDB heterodimeric protein complex with high specificity for binding to a variety of DNA helix-distorting lesions. DDB is believed to play a role in the initial step of damage recognition in mammalian nucleotide excision repair (NER) of ultraviolet light (UV)-induced photolesions. It has been shown that DDB2 is rapidly degraded after cellular UV irradiation. However, the relevance of DDB2 degradation to its functionality in NER is still unknown. Here, we have provided evidence that Cullin 4A (CUL-4A), a key component of CUL-4A-based ubiquitin ligase, mediates DDB2 degradation at the damage sites and regulates the recruitment of XPC and the repair of cyclobutane pyrimidine dimers. We have shown that CUL-4A can be identified in a UV-responsive protein complex containing both DDB subunits. CUL-4A was visualized in localized UV-irradiated sites together with DDB2 and XPC. Degradation of DDB2 could be blocked by silencing CUL-4A using small interference RNA or by treating cells with proteasome inhibitor MG132. This blockage resulted in prolonged retention of DDB2 at the subnuclear DNA damage foci within micropore irradiated cells. Knock down of CUL-4A also decreased recruitment of the damage recognition factor, XPC, to the damaged foci and concomitantly reduced the removal of cyclobutane pyrimidine dimers from the entire genome. These results suggest that CUL-4A mediates the proteolytic degradation of DDB2 and that this degradation event, initiated at the lesion sites, regulates damage recognition by XPC during the early steps of NER.
Use of differential surface charging to separate chemical differences in x‐ray photoelectron spectroscopy

Differential sample charging is a potential problem in x-ray photoelectron spectroscopic studies of insulating or partially conducting materials, especially when monochromatic x-radiation is used. The phenomenon can be exploited to distinguish between compounds that do not exhibit a significant chemical shift but do have significant differences in sample conductivity. This paper shows how sample biasing using large d.c. negative biases can be used to identify chemical differences in an important practical system consisting of oxide films on an aluminum alloy (6061) with a significant level of contamination involving a heavily contaminated dark area and a lightly contaminated light area. The two areas exhibit significantly different spectral behavior, but in both cases differential charging assists analysis, allowing different carbon environments (disordered graphitic carbon and lubricant hydrocarbons) to be distinguished. Changes in the aluminum and magnesium core regions allow an estimate of the differences in oxide thickness to be obtained. The use of positive sample biasing to eliminate differential sample biasing is also illustrated.
The effects of immobilization on bone histomorphometry in rats

To determine whether immobilization acts directly on bone by alteration of mechanical loading or systemically, studies of the effects of immobilization were carried out on histomorphometry of diaphyses of tibiae and on subcutaneous implants of demineralized allogenic bone matrix of rats. The right hind leg of growing rats was denervated by severing the tibial nerve. A sham operation on the right hind leg was performed in control animals. Bone formation at the endosteal and periosteal surfaces was significantly lower in tibiae from limbs with severed nerves as compared to tibiae from the intact limbs of nerve-sectioned rats and from both limbs of sham-operated control rats. Bone formation was decreased at both 3 and 7 weeks after immobilization. The decreased formation resulted in significant reductions in cross-sectional area. At 3 weeks post denervation, the periosteal bone formation rate was lower in tibiae of intact limbs from denervated rats as compared to tibiae from intact limbs of sham-operated animals. This finding was attributed to reduced physical activity of the denervated rats. In the implants, nerve section did not alter the amount of implant matrix resorbed, the amount of bone matrix synthesized, or the amount of calcium in the implant. These findings support the hypothesis that inhibition of bone formation at the tibial diaphysis in response to immobilization resulted from altered mechanical loading and not from the production of substances acting systemically. Whereas the mean medullary area of tibiae was not altered by nerve section, it was decreased in tibiae of all groups compared to the values of basal controls, indicating that bone formation was greater than bone resorption. The findings are interpreted to mean that, in the rat, reducing the mechanical loading of an extremity inhibits bone formation at the tibial diaphysis of the affected limb and does not influence bone resorption at that site.
Converting visual census data into absolute abundance estimates: a method for calibrating timed counts of a sedentary insect population

. 1. Visual surveys for small organisms on complex substrates often yield serious underestimates of true counts. When both visual counts (relative estimates of abundance) and absolute counts can be obtained from the same sample, however, the visual counts can be calibrated such that absolute estimates can be obtained in the future from visual surveys alone. 2. A method is presented for converting quick, timed, visual counts of a sedentary insect on a shrub into absolute estimates of abundance. 3. Analogies were drawn from simple, well-known predation theories to develop a two-parameter non-linear model. Parameter estimates were obtained by both inverse prediction and direct estimation methods; the latter were found to yield more accurate predictions of absolute abundance. 4. The calibration model is mechanistic in its approach, and thus has potential for application in other systems in which all individuals are visible, but able to be missed during timed counts.
The effect of sunlight on the protein crystals from Bacillus thuringiensis var. kurstaki HD1 and NRD12: a Raman spectroscopic study

Abstract The Raman spectrum of the endotoxin crystals from Bacillus thuringiensis var. kurstaki NRD12 is found to resemble closely that for crystals of the strain kurstaki HD1 (P. R. Carey et al., 1986). Since the Raman data provide detailed molecular information on the crystal proteins, the protoxins of HD1 and NRD12 must be in similar conformations in their respective crystals. Estimation of the protoxin secondary structure in NRD12 crystals, using the amide III and amide I′ Raman spectral features, gave 57% unordered, 25% α-helix, and 18% β-structure. This is very similar to the result for HD1, as is the finding that the aromatic amino acid side chains of the NRD12 protoxin in the crystal appear to have widespread accessibility to water molecules. The effect of sunlight irradiation on dried NRD12 or HD1 crystals was studied by recording the Raman spectrum of the crystals before and after irradiation under a solar simulator whose spectral output is essentially identical to that of sunlight at the earth's surface. The only Raman spectral change detected following 40-hr irradiation was a 35% reduction of the intensity of features near 760 and 1555 cm−1 due to tryptophan sidechains, indicating that irradiation brings about widespread destruction of indole residues. Control experiments using α-chymotrypsin, which has prominent tryptophan features in its Raman spectrum, show that the destruction of tryptophan is not brought about by the direct photolysis of the indole residues by the sunlight photons. Since silkworm bioassays on crystals of HD1 irradiated for 40 hr under the solar simulator or by natural sunlight showed that the crystals had become atoxic, the present results highlight the role of tryptophan destruction in sunlight-mediated crystal inactivation.
Rarity of males in pea aphids results in mutational decay.

When females can reproduce without males, do males become an evolutionarily weaker sex whose genes experience mutational decay? We addressed this hypothesis in aphids, whose reproduction alternates between parthenogenetic and sexual forms: Over the course of a year, there can be 10 to 20 generations of asexual females but only a single, if any, generation with males. We used microarray analyses to identify male-biased, asexual female‐biased, and neutral genes. Interspecific comparisons reveal accelerated evolution of male-biased genes, and intraspecific polymorphisms exhibit a significant excess of nonsynonymous coding variation in male-biased genes. We conclude that the ability of females to reproduce asexually without males reduces selection constraints on male-based genes, resulting in their mutational decay.
The Nogo66 receptor pathway and CNS axon regeneration: new hopes for treating CNS injuries and neurodegeneration

The neuronal leucine-rich repeat Nogo66 receptor (NgR) interacts with the myelin proteins Nogo66, myelin associated glycoprotein and oligodendrocyte myelin glycoprotein to inhibit axon growth. Modulation of these cell surface NgR-dependent interactions or the inhibitory intracellular signalling pathways may promote axon growth in the CNS after injury and present an attractive axon regeneration platform for treating CNS injuries or even neurodegenerative disorders. Multiple NgR antagonism approaches, including soluble NgR proteins, anti-NgR antibodies, a Nogo-derived antagonist peptide and NgR signal transduction modulators, have demonstrated striking efficacies in promoting functional recoveries in animal models of spinal cord injury, stroke and multiple sclerosis. This review summarises the neurobiology of the NgR pathway and the various drug discovery strategies that are specifically based on modulation of the myelin–NgR interaction.
Charge exchange in medium mass nuclei as observed by the (p, np) reaction

Abstract The cross sections for the (p, np) reaction, wherein the isobaric analogue state of the target nucleus formed by the (p, n) reaction decays by proton emission, has been measured as a function of bombarding energy (from 12.8 to 18 MeV) using as target nuclei: 67 Zn, 77 Se, 91 Zr, 95, 97 Mo, 105 Pd, 110, 111, 113 Cd 115, 116, 117, 119 Sn and 123, 125 Te. The analogue state is observed to undergo proton decay (p) to the ground state of the residual nucleus in all cases except 110 Cd where barrier penetration favors the decay of the first excited state. The fractional width for proton decay, Γ p /Γ, for the excited analogue states is inferred by comparison to 95 Mo and 115 Sn, which have Γ p /Γ = 1. These results are compared with the results of resonance experiments. The energy dependence of the cross sections can be reproduced by distorted wave calculations using a consistent charge independent formalism.
The application of micro-column solid phase extraction techniques for the determination of rare earth elements in actinide containing matrices

The design and characterization of an argon segmented-solid phase extraction system is described. A 200 ul volume micro-column has been constructed for the preconcentration of rare earth elements (REEs) from salt matrices containing uranium. An inductively coupled plasma atomic emission spectrometer has been utilized for simultaneous detection of Sr, Y and the REEs (namely Ce, Eu, La, Nd, Pr, Sm) at levels ranging from 5- to 2000 ppm in LiC1/KCl samples containing U. Preconcentration factors of 100 fold have been demonstrated. The precision, linear dynamic range and column performance of the system will be presented.
New emerging roles for epithelial cell extrusion

Epithelia use a unique process called 'cell extrusion' to remove cells from a layer, while preserving their barrier function. Specifically, a cell destined to die triggers formation of an actin and myosin-ring in the live neighboring epithelial cells surrounding it, which squeeze the dying cell out. During extrusion, the surrounding cells expand toward one another and meet to fill the gap left by the extruded cell. Recent studies have revealed new roles of extrusion in controlling developmental morphogenesis, maintaining homeostatic cell numbers, and how this process is usurped during bacterial pathogenesis. Here, we review recent advances in new processes that require cell extrusion and the signaling pathways controlling it.
Retrograde Cerebral Perfusion Is an Effective Means of Neural Support During Deep Hypothermic Circulatory Arrest

With the current available information, the use of RCP for cerebral protection during HCA in the clinical setting will continue to be debated. Laboratory evaluation in a variety of animal models has thus far produced conflicting results and a variety of mixed information. Accumulating clinical evidence has confirmed that RCP is safe, provided flow rates and central venous (intracerebral) pressures are maintained at relatively low levels. The use of RCP is clinically safe and does not incur additional expense. In the event that the only clinical benefits of RCP are the maintenance of cerebral hypothermia and the flushing of air and particulate debris from the arterial circulation, consequently reducing the risk of embolism, then the continued use and investigation of RCP techniques is justified.
Column chromatographic purification of octanoyl-CoA.

Abstract 1. 1. A column chromatographic procedure for the purification of intermediate chain length acyl-CoA's is described. Chromatography is on DEAE-cellulose and is dependent on the conversion of free excess CoA to the mixed disulfide of CoA and thionitrobenzoate. The procedure is rapid and large amounts of acyl-CoA can be handled with good recovery. 2. 2. 3H-CoA has been prepared and purified by this method. The product showed high biological activity.
Liberation-limited grade/recovery curves from X-ray micro CT analysis of feed material for the evaluation of separation efficiency

Abstract Procedures for 3D mineral liberation analysis by X-ray micro CT (XMT) are presented and discussed including the construction of liberation-limited grade/recovery curves for specific feed materials. In this way, actual separation efficiencies can be compared to what might be expected for a perfect separation limited only by the extent of liberation. It is shown that 3D mineral liberation analysis based on XMT is preferred to 2D section analysis which overestimates the extent of liberation. By way of example, procedures and experimental results are presented and discussed for feed material in the case of phosphate rock flotation.
Operational equations for data in rectangular array

Abstract It is widely regarded as impossible to estimate curvature on four points in rectangular array. This paper presents equations that estimate curvature on such data. One of the equations is analogous to the parabola for three equidistant, curvilinear data. The other equations are based on exponential functions. They are usually superior to the bilinear equation if the L2 norm test is the criterion of merit.
Freshwater inflow: Science, policy, management

The papers in this special issue were presented in a special session during the 2001 biennial conference of the Estuarine Research Federation held in St. Pete Beach, Florida. The session, “Freshwater inflow: Science, policy and management,” was focused on issues related to reduced freshwater inflow to estuaries. The session brought together scientists, managers, and regulators, and included presentations on the estimation of freshwater input to estuaries, development of ecological indicators to assess changes in inflow, management strategies used to set freshwater requirements, and experiences with the reintroduction of freshwater to restore inflow.
EFFICACY OF SELECTED INSECTICIDES ON CABBAGE LOOPER AND DIAMONDBACK MOTH ON CABBAGE, SPRING 2004

The test was conducted at the Texas A&M University Agricultural Research and Extension Center at Weslaco, TX. The objective of this trial was to test the efficacy of some newer insecticides for controlling cabbage looper and diamondback moth on cabbage under field conditions in south Texas in the spring, 2004. The materials were applied using a tractor-mounted sprayer with 3 ceramic hollow cone nozzles per row (TX-10, one over the plants, two on drops) at 100 psi at a delivery rate of 30 gpa. Numbers of small and large larvae of cabbage looper and diamondback moth were counted by checking both the upper and lower surfaces of every leaf on each plant, and 10 plants per plot. At termination, a damage/quality evaluation was made on ten plants per plot based on the following six categories: 0-no damage, 1-minor feeding damage (1% eaten), 2-minor-moderate feeding damage (2-5% eaten), 3-moderate damage (6-10% eaten), 4-moderate-heavy damage (11-30% eaten), and 5-heavy damage (>30% eaten). Numbers of larvae per plant from each plot and the damage rankings were subjected to ANOVA, and the means were separated using LSD (P ≤ 0.05).
Search for new heaven leptons at LEP

Abstract The energy upgrade at LEP allows new regimes to be explored in the search for New Physics. In this paper the preliminary results on searches for new 4th generation sequential leptons and excited leptons at √ s = 161 and 172 GeV are presented.
256 THEOPHYLLINE HALF-LIFE IN INFANTS AND YOUNG CHILDREN

Theophylline half-life determination kinetics were performed in 54 young children. Our patients ranged in age from three months to six years, with a mean age of 2.2 years. Mean half-life determined was 4.92 hours with a standard deviation of 1.88 hours, which is at considerable variance with previously quoted half-lives for young children. Computerized multiple regression analyses with doses of 3, 4, 5 mg/kg of theophylline every six hours were performed, and maximum, minimum, and mean steady state serum levels were developed. Five mg/kg theophylline appeared to be a safe dosage in the majority of children. Two of our subjects developed peak levels greater than 25 mcg/ml, and no toxicity was noted. Age and half-lives were compared, and there was found to be no correlation in this young age group. Theophylline half-life in young children was found to be considerably longer than previously recorded. The published values of theophylline safety range levels, e.g., less than 20 mcg/ml, need to be reconsidered.
Nitric oxide regulation of ADP-ribosylation of G proteins in hypertension

Nitric oxide stimulates endogenous ADP-ribosylation of cytosolic and membrane-bound proteins. Endogenous ADP-ribosyltransferases modify several intracellular proteins including the heterotrimeric GTP-binding proteins (G proteins). ADP-ribosylation of G proteins in vascular smooth muscle leads to increased activation of adenylate cyclase and decreased activation of phospholipase C leading to vasodilation. We hypothesize that in hypertension, chronically depressed endothelium-derived nitric oxide levels lead to decreased ADP-ribosylation of G proteins. This reduced ADP-ribosylation leads to vasoconstriction since activation of the G proteins by agonists is unopposed. Thus, disinhibition of G proteins, mediated by nitric oxide deficit, is responsible for the observed increased sensitivity to vasoconstrictor agonists in hypertension. This novel role for nitric oxide in hypertension will provide a new area of research for antihypertensive therapeutic intervention.
Photoemission from excitons in organic semiconductors

Abstract An exciton is an atomic hydrogen-like quasi-particle, consisting of a Coulombically bound pair of an electron and a hole in conduction and valence bands, respectively. While excitons are traditionally investigated by optical spectroscopies, photoelectron spectroscopy can be a powerful tool in providing a unique view on the energetics and dynamics of excitons in semiconductor materials. The experiment typically relies on time-resolved two-photon photoemission (TR-2PPE) spectroscopy in which the first laser pulse creates excitons in a material and the second laser pulse ionizes the excitons for detection. In this short note, I discuss unique insights provided by TR-2PPE on exciton dynamics in organic semiconductors and challenges in the application of this technique.
Re-hosting a computer assisted wargame exercise from a mainframe to a micro: database and user-interface issues

This paper addresses the issues concerned with transporting a large-scale, computer assisted, warfare exercise program from a mainframe to a microcomputer environment. Its main focus is on replacing the current application dependent file system with a commercial DBMS and using a 4th generation language applications development tool to develop a more friendly user interface. Issues concerned with database and user interface design are discussed.
The borehole temperature record of climate warming in the mid-continent of North America

Abstract Ground-surface temperature (GST) histories, determined from a carefully selected set of twenty-nine borehole temperature profiles, show a warming trend over the last century that increases systematically with latitude in the mid-continent of North America. Except one site in north Texas, the borehole locations lie within a 500 × 1000 km transect that extends from the Kansas-Nebraska border into southern Manitoba. Ground-surface warming during the last century increases from +0.4°C at 41.1°N to + 2.0°C at 49.6°N. Surface air temperature (SAT) warming in the transect, determined from Historical Climatology Network stations, increases from + 0.5°C per century at 40°C per century at 48.8°N. These warming trends agree with the regional warming pattern predicted by GCM simulations of global warming. However, the magnitudes of warming determined from the GST and the SAT data agree in regions where seasonal ground freezing does not occur but differ significantly where seasonal ground freezing does occur. Analysis of ground and air temperature coupling suggests that the greater warming observed in the GST histories in seasonally frozen ground is due to a secular increase in soil moisture that corresponds with increased precipitation during the past 50 years.