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In June 1994, the Texas Center for Educational Technology (TCET) posted a survey on several educational listservs and conference groups on the Internet requesting comments, observations, and opinions from educators having experience with telephones in classrooms. Most of the respondents agreed on the need to equip K-12 classrooms with modern communications tools including telephone lines to be used predominately for voice and computer communications. They indicated that the advantages of voice communications are improved parent/teacher and intra-and inter-campus communication, better discipline management, and increased teacher and student morale. Computer communications is beneficial because it allows teachers and students access to information for conducting research in almost any area of K-12 curriculum via e-mail, e-mail lists, newsgroups and the exchange of documents and data files. Potential negatives of voice and computer communications include abuse of the telephone line, disruptive phone ringing, that the telephone line is not the best access to the Internet, and that "garbage" is accessible through the Internet. FAX machines are another mode of communication via telephone lines, and can be used to send and receive information. The principal deterrent to the installation of telephone lines in the classroom is the cost. (MAS/DGM)

AbsractGenitourinary manifestations are rare in patients with Crohn’s disease, and a small percentage of patients will experience enterocutaneous fistulas. Infection is one of the most common complications associated with inflatable penile prosthesis placement, which can be associated with fistula formation. In this report, we present a patient with Crohn’s disease who developed an inflatable penile prosthesis infection secondary to an undiagnosed enterocutaneous fistula.

Neoadjuvant immune-checkpoint inhibition is a promising emerging treatment approach for patients with surgically resectable macroscopic stage III melanoma. The neoadjuvant setting provides an ideal platform for personalized therapy owing to the very homogeneous nature of the patient population and the opportunity for pathological response assessments within several weeks of starting treatment, thereby facilitating the efficient identification of novel biomarkers. A pathological response to immune-checkpoint inhibitors has been shown to be a strong surrogate marker of both recurrence-free survival and overall survival, enabling timely analyses of the efficacy of novel therapies in patients with early stage disease. Patients with a major pathological response (defined as the presence of ≤10% viable tumour cells) have a very low risk of recurrence, which offers an opportunity to adjust the extent of surgery and any subsequent adjuvant therapy and follow-up monitoring. Conversely, patients who have only a partial pathological response or who do not respond to neoadjuvant therapy still might benefit from therapy escalation and/or class switch during adjuvant therapy. In this Review, we outline the concept of a fully personalized neoadjuvant treatment approach exemplified by the current developments in neoadjuvant therapy for patients with resectable melanoma, which could provide a template for the development of similar approaches for patients with other immune-responsive cancers in the near future.

Abstract:Although there is a growing body of literature on sexualized violence during the Holocaust, little scholarship discusses the topic of second-generation inherited sexualized trauma. We explore the subject of inherited sexualized trauma because it is not uncommon to second-generation women, as evidenced by the multiple representations of daughters of survivors who engage in Holocaust-related eroticisms. To make use of a generative case study, we examine Sonia Pilcer’s The Holocaust Kid. The protagonist, Zosha Palovsky, engages in Nazi-Jewess erotic fantasy and role play as a way of addressing, albeit obliquely, her inherited sexualized trauma. Drawing upon the power dynamics described in dominant-submissive sexual fantasies and encounters within Bondage/Domination/Sado-Masochism (BDSM) theory, we suggest that Zosha, by willfully submitting and allowing herself to be sexually dominated by a “Nazi,” paradoxically is in control of the erotic encounter. This control enables her to vicariously assert a measure of agency on behalf of her mother who was stripped of bodily autonomy in Auschwitz. Her vicarious assertion of agency functions as a means of negotiating her postmemory of sexualized violence during the Shoah.

The extended focused assessment with sonography for trauma (eFAST) ultrasound examination is an essential step in the initial assessment of trauma patients. Its accuracy depends on the ability to acquire high-quality ultrasound images, and we hypothesized that increasing BMI was associated with increased odds for incorrect eFAST. All adult blunt trauma activations at a high-volume urban trauma center in 2016 that underwent eFAST and CT chest, abdomen, and pelvis were included (n = 446). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the eFAST were calculated with CT results as reference. The association of BMI and eFAST accuracy was determined using univariate analyses. Sensitivity and specificity of the eFASTexamination were 27.1 per cent and 91.7 per cent, respectively, with an overall 76.2 per cent accuracy. At BMI 36 kg/m2, the odds of having incorrect eFAST results increased to odds ratio (OR) = 1.85 (95% confidence interval, 1.03–3.32; P= 0.05). For those with BMI > 40 kg/m2, the OR increased to OR = 3.12 (95% confidence interval, 1.45–6.69; P= 0.01). One-third of patients in this study were obese or morbidly obese. The latter was associated with increased odds for incorrect eFAST results, particularly the abdominal examination component.

This paper describes an experimental study (N = 184) that investigated influence and social distance consequences of a number of attributes in interpersonal interactions. The attributes included race, education, panic disorder, depression, and schizophrenia. Participants interacted with fictitious partners whom they believed were real and who represented the attributes studied. Participants had opportunities to be influenced by and seek distance from their interaction partners. Results showed that low educational attainment and schizophrenia significantly reduced the influence of partners. Participants sought significantly more social distance from partners who were African American and partners with depression or schizophrenia than other partners. The results are noteworthy in (1) finding that race did not affect influence in the sample but did affect social distance; (2) showing that different mental illness labels led to different reactions, with schizophrenia leading to particularly strong negative reactions; and (3) demonstrating these effects behaviorally in an interactional setting.

AbstractAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive loss of motor neurons. ALS can be modeled in zebrafish (Danio rerio) through the expression of human ALS-causing genes, such as superoxide dismutase 1 (SOD1). Overexpression of mutated human SOD1 protein causes aberrant branching and shortening of spinal motor axons. Despite this, the functional relevance of this axon morphology remains elusive. Our aim was to determine whether this motor axonopathy is correlated with impaired movement in mutant (MT) SOD1-expressing zebrafish. Transgenic zebrafish embryos that express blue fluorescent protein (mTagBFP) in motor neurons were injected with either wild-type (WT) or MT (A4V) human SOD1 messenger ribonucleic acid (mRNA). At 48 hours post-fertilization, larvae movement (distance traveled during behavioral testing) was examined, followed by quantification of motor axon length. Larvae injected with MT SOD1 mRNA had significantly shorter and more aberrantly branched motor axons (p< 0.002) and traveled a significantly shorter distance during behavioral testing (p< 0.001) when compared with WT SOD1 and noninjected larvae. Furthermore, there was a positive correlation between distance traveled and motor axon length (R2= 0.357, p< 0.001). These data represent the first correlative investigation of motor axonopathies and impaired movement in SOD1-expressing zebrafish, confirming functional relevance and validating movement as a disease phenotype for the testing of disease treatments for ALS.

Context.We report on the first ultracool dwarf discoveries from the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey Early Data Release (LAS EDR), in particular the discovery of T dwarfs which are fainter and more distant than those found using the 2MASS and SDSS surveys.

The article offers the author's insights on teaching operational research (OR) among the students at Naval Postgraduate School (NPS).

The resection of anterior skull base meningiomas has traditionally been performed via pterional or unilateral/bilateral subfrontal craniotomies. The supraorbital keyhole approach and the endoscopic endonasal approach, techniques in which the endoscope is used to aid visualization, were developed to provide alternative, less-invasive approaches to aid the resection of these tumors. The individual characteristics of each tumor, such as location and size, are the main determinants guiding the choice of approach. In this article, the advantages and disadvantages of each approach are discussed, along with complications specific to each technique. Furthermore, a detailed procedural description of each surgical approach is described.

A new phenomenological model of the nucleus has been constructed by separately modeling a proton and a neutron using a classical electromagnetic approach first suggested by Arthur Compton and later elaborated from plasma physics experiments conducted by his student, Winston Bostick. Using these two nucleon representations, different nuclei are arranged by placing neutrons and protons in static geometric positions, where the force balance has minimum energy. These positions have been verified numerically using a variational minimization technique. This suggests that mechanical vibration is a valid physical mechanism for decay. For the first time, the pattern of all the magic number closed nucleon-shells is accurately predicted, and new magic numbers have been found. These numbers have been verified against experimental data. The masses of all individual isotopes that were calculated are in agreement with the measured values within less than a tenth of a percent, thus mimicking the experimentally measured binding energy per nucleon curve. An extension of this idea to model electrons in atoms also predicts the pattern of the Periodic Table of the Elements.

The evasion of apoptosis is a key characteristic of cancer, and thus strategies to selectively induce apoptosis in cancer cells hold considerable promise in personalized anticancer therapy. Structurally similar procaspase activating compounds PAC-1 and S-PAC-1 restore procaspase-3 activity through the chelation of inhibitory zinc ions in vitro, induce apoptotic death of cancer cells in culture, and reduce tumor burden in vivo. Ip or iv administrations of high doses of PAC-1 are transiently neurotoxic in vivo, while S-PAC-1 is safe even at very high doses and has been evaluated in a phase I clinical trial of pet dogs with spontaneously occurring lymphoma. Here we show that PAC-1 and S-PAC-1 have similar mechanisms of cell death induction at low concentrations (less than 50 μM), but at high concentrations PAC-1 displays unique cell death induction features. Cells treated with a high concentration of PAC-1 have a distinctive gene expression profile, unusual cellular and mitochondrial morphology, and an altered intracellular Ca2+concentration, indicative of endoplasmic reticulum (ER) stress-induced apoptosis. These studies suggest strategies for anticancer clinical development, specifically bolus dosing for PAC-1 and continuous rate infusion for S-PAC-1.

Here, we show how the mechanical properties of a thick-shelled tropical seed are adapted to permit them to germinate while preventing their predation. The seed has evolved a complex heterogeneous microstructure resulting in hardness, stiffness and fracture toughness values that place the structure at the intersection of these competing selective constraints. Analyses of different damage mechanisms inflicted by beetles, squirrels and orangutans illustrate that cellular shapes and orientations ensure damage resistance to predation forces imposed across a broad range of length scales. This resistance is shown to be around the upper limit that allows cracking the shell via internal turgor pressure (i.e. germination). Thus, the seed appears to strike an exquisitely delicate adaptive balance between multiple selection pressures.

Hi-GAL, the Herschel infrared Galactic Plane Survey, is an Open Time Key Project of the Herschel Space Observatory. It will make an unbiased photometric survey of the inner Galactic plane by mapping a 2° wide strip in the longitude range ?l? < 60° in five wavebands between 70 ?m and 500 ?m. The aim of Hi-GAL is to detect the earliest phases of the formation of molecular clouds and high-mass stars and to use the optimum combination of Herschelwavelength coverage, sensitivity, mapping strategy, and speed to deliver a homogeneous census of star-forming regions and cold structures in the interstellar medium. The resulting representative samples will yield the variation of source temperature, luminosity, mass and age in a wide range of Galactic environments at all scales from massive YSOs in protoclusters to entire spiral arms, providing an evolutionary sequence for the formation of intermediate and high-mass stars. This information is essential to the formulation of a predictive global model of the role of environment and feedback in regulating the star-formation process. Such a model is vital to understanding star formation on galactic scales and in the early universe. Hi-GAL will also provide a science legacy for decades to come with incalculable potential for systematic and serendipitous science in a wide range of astronomical fields, enabling the optimum use of future major facilities such as JWSTand ALMA.

It is important to recognize the possibility of a syndromic etiology of cardiac defects when dysmorphic features and other congenital defects are present. We report a patient who presented with atrial fibrillation and was found to have an abnormal mitral valve, congenital aneurysm of the left atrial appendage, and features consistent with both Cardiofaciocutaneous syndrome and Noonan syndrome. The congenital aneurysm of the left atrial appendage was a previously unreported cardiac presentation for either syndrome. Diagnostic considerations based upon his genotype and phenotype are discussed, along with his unique cardiac presentation and treatment.

To describe the metric measurements and normal anatomic variants in Chinese bony orbits.

We have built and used on several occasions an optical broadband stellar polarimeter, PlanetPol, which employs photoelastic modulators and avalanche photodiodes and achieves a photon-noise-limited sensitivity of at least 1 in 106in fractional polarization. Observations of a number of polarized standards taken from the literature show that the accuracy of polarization measurements is ?1%. We have developed a method for accurately measuring the polarization of altitude-azimuth mounted telescopes by observing bright nearby stars at different parallactic angles, and we find that the on-axis polarization of the William Herschel Telescope is typically ?15 × 10?6, measured with an accuracy of a few parts in 107. The nearby stars (distance less than 32 pc) are found to have very low polarizations, typically a few ×10?6, indicating that very little interstellar polarization is produced close to the Sun and that their intrinsic polarization is also low. Although the polarimeter can be used for a wide range of astronomy, the very high sensitivity was set by the goal of detecting the polarization signature of unresolved extrasolar planets.

To elucidate the characteristics and location of the supraorbital and frontal exits of the supraorbital nerve in Chinese skulls and to compare these findings with other ethnic populations.

Lanchester equations and their extensions are widely used to calculate attrition in models of warfare. This paper examines how Lanchester models fit detailed daily data on the battles of Kursk and Ardennes. The data on Kursk, often called the greatest tank battle in history, was only recently made available. A new approach is used to find the optimal parameter values and gain an understanding of how well various parameter combinations explain the battles. It turns out that a variety of Lanchester models fit the data about as well. This explains why previous studies on Ardennes, using different minimization techniques and data formulations, have found disparate optimal fits. We also find that none of the basic Lanchester laws (i.e., square, linear, and logarithmic) fit the data particularly well or consistently perform better than the others. This means that it does not matter which of these laws you use, for with the right coefficients you will get about the same result. Furthermore, no constant attrition coefficient Lanchester law fits very well. The failure to find a good-fitting Lanchester model suggests that it may be beneficial to look for new ways to model highly aggregated attrition. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.

There are multiple damage functions in the literature to estimate the probability that a single weapon detonation destroys a point target. This paper addresses differences in the tails of four of the more popular damage functions. These four cover the asymptotic tail behaviors of all monotonically decreasing damage functions with well-behaved hazard functions. The differences in estimates of probability of kill are quite dramatic for large aim-point offsets. This is particularly important when balancing the number of threats that can be engaged with the chances of fratricide and collateral damage. In general, analysts substituting one damage function for another may badly estimate kill probabilities in offset-aiming, which could result in poor doctrine. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 306–321, 2003.

The simulations that many defense analysts rely upon in their studies continue to grow in size and complexity. This paper contrasts the guidance that the authors have received—from some of the giants of military operations research—with the current practice. In particular, the analytic utility of Hughes' simple salvo equations is compared with that of the complex Joint Warfighting System (JWARS), with respect to JWARS' key performance parameters. The comparison suggests that a family of analytic tools supports the best analyses. It follows that smaller, more agile, and transparent models, such as Hughes' salvo equations, are underutilized in defense analyses. We believe that these models should receive more attention, use, and funding. To illustrate this point, this paper uses two very simple models (by modern standards) to rapidly generate insights on the value of information relative to force strength. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2003

Brome mosaic virus (BMV), a T= 3 icosahedral plant virus, can be dissociated into coat protein subunits and subunit oligomers at pH 7.5 in the presence of concentrated salts. We have found that during the course of this treatment the coat protein subunits are cleaved, presumably by plant cell proteases still present in the preparation, between amino acids 35 and 36. The truncated protein subunits will then reorganize into T= 1 icosahedral particles and can be crystallized from sodium malonate. Quasi elastic light scattering and atomic force microscopy results suggest that the transition from T= 3 to T= 1 particles can occur by separate pathways, dissociation into coat protein subunits and oligomers and reassembly into T= 1 particles, or direct condensation of the T= 3 virions to T= 1 particles with the shedding of hexameric capsomeres. The latter process has been directly visualized using atomic force microscopy. Native T= 3 virions have been crystallized in several different crystal forms, but neither a rhombohedral form nor either of two orthorhombic forms diffract beyond about 3.4 Å. Tetragonal crystals of the T= 1 particles, however, diffract to at least 2.5 Å resolution. Evidence suggests that the T= 1 particles are more structurally uniform and ordered than are native T= 3 virions. A variety of anomalous virus particles having diverse sizes have been visualized in preparations of BMV used for crystallization. In some cases these aberrant particles are incorporated into growing crystals where they are frequently responsible for defect formation.

Canopy‐top leaves of the dominant tree species from two 0.96‐ha plots in Brunei, northern Borneo, were sampled for structural and chemical analysis. Thirteen species from the mixed dipterocarp forest at Andulau and 14 from the lowland heath forest at Badas were studied. The heath‐forest species had significantly thicker leaves and were lower in nitrogen and ash concentration than those from the mixed dipterocarp forest. There were no significant differences between the two species groups in leaf mass per unit area (LMA), leaf fracture toughness, carbon concentration, 813C, neutral detergent fiber concentration, sclerophylly index, and stomatal density. A significant negative correlation between %C and 813C was found for the species from the mixed dipterocarp forest, but not those from the heath forest. The degree of sclerophylly measured in physical terms overlapped between the two sites to a considerable degree; however, all six species tested that were present in both plots had higher leaf fracture toughness in the heath forest. The possible reasons for the marked sclerophylly in the mixed dipterocarp forest are discussed.

The persistent trigeminal artery (PTA) is the largest and most commonly occurring type of remnant fetal arteries, typically originating from the posterior bend or lateral wall of the intracavernous carotid artery. There are no published reports of coexisting PTA and midline epithelial tumors.

In situatomic force microscopy (AFM) was used to investigate surface evolution during the growth of single crystals of turnip yellow mosaic virus (TYMV). Growth of the (101) face of TYMV crystals proceeded by two-dimensional nucleation. The molecular structure of the step edges and adsorption of individual virus particles and their aggregates on the crystalline surface were recorded. The surfaces of individual virions within crystals were visualized and seen to be quite distinctive with the hexameric and pentameric capsomers of the T= 3 capsids being clearly resolved. This, so far as we are aware, is the first direct visualization of the capsomere structure of a virus by AFM. In the course of recording the in situdevelopment of the crystals, a profound restructuring of the surface arrangement was observed. This transformation was highly cooperative in nature, but the transitions were unambiguous and readily explicable in terms of an organized loss of classes of virus particles from specific lattice positions. In some cases areas of a single crystal surface were recorded in which were captured successive phases of the transition. We believe this provides the first visual record of a cooperative restructuring of the surface of a supramolecular crystal.

Xanthine phosphoribosyltransferase (XPRT) from Leishmania donovani is a unique enzyme that lacks a mammalian counterpart and is, therefore, a potential target for antiparasitic therapy. To investigate the enzyme at the molecular and biochemical level, a cDNA encoding the L. donovani XPRT was isolated by functional complementation of a purine auxotroph of Escherichia coli that also harbors deficiencies in the prokaryotic phosphoribosyltransferase (PRT) activities. The cDNA was then used to isolate the XPRT genomic clone. XPRT encodes a 241-amino acid protein exhibiting approximately 33% amino acid identity with the L. donovani hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and significant homology with other HGPRT family members. Southern blot analysis revealed that XPRT was a single copy gene that co-localized with HGPRT within a 4.3-kilobase pair (kb) EcoRI fragment, implying that the two genes arose as a result of an ancestral duplication event. Sequencing of this EcoRI fragment confirmed that HGPRT and XPRT were organized in a head-to-tail arrangement separated by an approximately 2.2-kb intergenic region. Both the 3.2-kb XPRT mRNA and XPRT enzyme were significantly up-regulated in Deltahgprt and Deltahgprt/Deltaaprt L. donovani mutants. Genetic obliteration of the XPRT locus by targeted gene replacement indicated that XPRT was not an essential gene under most conditions and that the Deltaxprt null strain was competent of salvaging all purines except xanthine. XPRT was overexpressed in E. coli and the recombinant protein purified to homogeneity. Kinetic analysis revealed that the XPRT preferentially phosphoribosylated xanthine but could also recognize hypoxanthine and guanine. K(m) values of 7.1, 448.0, and >100 microM and k(cat) values of 3.5, 2.6, and approximately 0.003 s(-1) were calculated for xanthine, hypoxanthine, and guanine, respectively. The XPRT gene and XPRT protein provide the requisite molecular and biochemical reagents for subsequent studies to validate XPRT as a potential therapeutic target.

Each year millions of people suffer tissue loss or end-stage organ failure. While allogeneic therapies have saved and improved countless lives, they remain imperfect solutions. These therapies are limited by critical donor shortages, long-term morbidity, and mortality. A wide variety of transplants, congenital malformations, elective surgeries, and genetic disorders have the potential for treatment with autologous stem cells as a source of HLA-matched donor tissue. Our current research is aimed at characterizing cell surface cluster differentiation (CD) markers on human progenitor and pluripotent cells to aid in isolating comparatively purified populations of these cells. This study examined human pluripotent and progenitor cells isolated from fetal, mature, and geriatric individuals for the possible presence of 15 CD markers. The response to insulin and dexamethasone revealed that the cell isolates were composed of lineage-committed progenitor cells and lineage-uncommitted pluripotent cells. Flow cytometry showed cell populations positive for CD10, CD13, CD56, and MHC Class-I markers and negative for CD3, CD5, CD7, CD11b, CD14, CD15, CD16, CD19, CD25, CD45, and CD65 markers. Northern analysis revealed that CD13 and CD56 were actively transcribed at time of cell harvest. We report the first identification of CD10, CD13, CD56, and MHC Class-I cell surface antigens on these human cells.

The repair of large and/or recurrent ventral hernias is associated with significant complications and a recurrence rate that can be more than 50 per cent. Laparoscopic ventral herniorrhaphy, a recent development, has been shown to be safe and effective in the repair of ventral hernias. This study retrospectively reviews all ventral hernia repairs over a 3-year period, November 1995 through December 1998, at a community-based teaching hospital. The purpose of the study was to compare open and laparoscopic repairs. A total of 253 ventral hernia repairs were performed during this time, 174 open and 79 laparoscopic. The age, weight, and sex distribution was similar for each group. The hernias in the open group averaged 34.1 cm2in size, and mesh used averaged 47.3 cm2. In the laparoscopic group, the hernia defect averaged 73.0 cm2, and the mesh size averaged 287.4 cm2. Operative time was longer in the open group, 82.0 versus 58.0 minutes. In the open group, there were 38 (21.8%) minor and 8 (4.6%) major complications, compared with 13 (16.5%) minor and 2 (2.5%) major complications in the laparoscopic group. Hospital stay was shorter for the laparoscopic group, 1.7 versus 2.8 days. At an average follow-up of 21 months (range, 2–40 months), there have been 36 recurrences in the open group (20.7%) compared with 2 recurrences in the laparoscopic group (2.5%). In this series, laparoscopic ventral herniorrhaphy compares favorably to open ventral herniorrhaphy with respect to wound complications, hospital stay, operative time, and recurrence rate.

The crystal structure relationships between the four thermal polymorphs (IV – 437 K – III – 492 K – II – 564 K – I) of RbNO3are discussed. Trigonal IV, a = 10.55(2), c = 7.47(2) Å at 298 K, Z = 9, and space group P31(or its enantiomorph P32) has Rb atoms arranged on a pseudocubic sublattice defined by and related segments. The ordered NO3groups are enclosed within respective pseudocubes and form close to ideal 8-fold anion–cation coordination with the surrounding Rb atoms. At IV → III, each of the appropriate (1/3) <10.1> and (1/3) <11.1> segments of IV (forming the Rb atom sublattice) transform to a cell edge of an ideal s.c. lattice of Rb atoms, a = 4.39(1) Å, Z = 1, and space group Pm3m. The orientationally disordered NO3groups in III form another close to ideal 8-fold anion–cation coordination with the Rb atoms. At III → II, the s.c. lattice of III changes to form a larger b.c.c. lattice, a = 8.84(3) Å, Z = 8, in II. A parallel-axes unit cell relationship, i.e. <100>III//<100>IIand 2(a)III = (a)II, exists between III and II. The NO3group in II is postulated to form a close to ideal 8-fold anion–cation coordination with the surrounding Rb atoms. At II → I, II transforms to a f.c.c. lattice, a = 7.32 Å, Z = 4, and space group Fm3m. The NO3group in I forms a close to ideal 6-fold anion–cation coordination with the surrounding Rb atoms. It is suggested that and related segments in II, which form a trigonal Rb atom sublattice, a = 7.65(3) Å and α = 109.47°, after II → I, transform to orthogonal cell edges of the cubic lattice of I.

An attempt was made to establish the nature of and some of the factors influencing the adsorption of caesium ions in solution on to a range of solid materials; polyvinyl chloride (PVC), barytes, china clay, whiting, carbon black, titania, asbestos, chosen since they are all used in the manufacture of a range of products used for surface coatings and storage vessels. Particular attention was paid to the use of products containing these compounds which are recommended for use in radioactive areas, both for the storage of radioactive materials and the protection of surfaces, where contamination can present problems. The adsorption processes were investigated by preparing and analysing the characteristics of the adsorption isotherms of caesium ions on to powder samples using a batch equilibration technique, and as was to be expected the predominant mechanism appeared to be one of ion exchange. It was confirmed that titania, and to a lesser extent china clay, whiting and carbon black, played a major part in the adsorption process. It is clear that the quality of any final product will depend on the process used in its manufacture, which in turn can be related to its potential for contamination in a radioactive facility.

Mammalian mastication is a process combining simultaneous food comminution and lubrication. The initiation of swallowing, which is voluntary, has been thought to depend on separate thresholds for food particle size and for particle lubrication. Instead of this duality, we suggest that swallowing is initiated when it is sensed that a batch of food particles is binding together under viscous forces so as to form a bolus. Bolus formation ensures that when the food mass is swallowed, it will pass the pharyngeal region safely without risk of inhaling small particles into the lower respiratory tract. Crucial for bolus formation is food particle size reduction by mastication. This allows the tongue to pack particles together tightly by pressure against the hard palate. A major function of salivation is to fill the gradually reducing spaces between particles, so increasing viscous cohesion and promoting bolus formation. If swallowing is delayed, excessive saliva floods the bolus, separating particles and reducing cohesion. Swallowing then becomes more precarious. Our model suggests that there is an optimum moment for a mammal to swallow, defined in terms of a peak cohesive force between food particles. The model is tested on human mastication with two foods, brazil nut and raw carrot, which have very different particle size breakdown rates. The peak cohesive force is much greater with brazil nuts but both foods are predicted to be swallowed after similar numbers of chews despite the very different food particle size reductions achieved at that stage. The predicted number of chews to swallow is in broad agreement with published data.

A direct measurement has shown that the ionization energy required to produce electron-hole pairs in a silicon detector is independent of whether the incident 160 MeV α-particles used are channelled or not, to an accuracy of about 2%.

The value placed by the public on the nation's rural landscapes is emphasised by vociferous criticism of insensitive, large-scale afforestation. As forestry causes massive changes in the landscape in the short term, with results that last for decades, the opportunity provided to improve and conserve should be positively grasped. There is evidence that concensus exists over a considerable part of landscape and design, and this paper explores some of the major factors in landscape design which are consistently important in forest landscapes.

Mung bean starch gels, of 4.5-14 wt % solid content, were stored at room temperature and at 4°C in a refrigerator and then cracked quasi-statically by driving a 40° included-angle wedge into intact specimens in order to determine their fracture toughness. The work to fracture of the gels, calculated without respect to energy loss due to viscoelasticity or to frictional effects between wedge and gel, varied from 0.5 to 22 J m-2 and were higher for those gels stored at low temperature. For gels stored at room temperature, the effect of viscoelasticity and wedge-gel friction was examined. Hysteresis (viscoelastic energy losses) was concentrationdependent. In 8 wt % gels, it accounted for about 10% of the total work done in the wedge tests and did not depend significantly on crosshead speed. Frictional work, largely due to adhesion between the gel and the wedge, was negligible at low speeds but increased rapidly with crosshead speed. However, whether correction factors are introduced or not, the results substantiate the very low fracture toughness of gels. Between 5 and 11 wt % concentrations, the work of fracture varied linearly with gel concentration. Variation in crosshead speed from 2 to 200 mm min-1 increased the work to fracture by a factor of two.

1. Although some disease classes can be defined by a single defining characteristic, in terms of traditional logic one that is both necessary and sufficient, other disease classes, such as the so-called ‘irritable bowel syndrome’ (IBS), have only a set of symptoms, signs etc. which are said to chatacterize it in some undefined way. 2. This characterization might be made definite by using simple Boolean algebra to give a logical description of the disease class. 3. This method can only be used if the individual doctor can be shown to be consistent in his assignment of a set of data to the disease class and also if his assignment agrees independently with that of another doctor. 4. To test such consistency and concordance, 100 case records were collected of supposed IBS and not-IBS; 20 of these were replicated to test consistency, and the total of 120 records was examined by five consultants independently, who assigned them either to an IBS or a not-IBS class. 5. From the 1500 pair-wise comparisons, analysis revealed that the disagreement in assignment between doctors was only slightly greater than the disagreement within doctors, suggesting that the group of doctors acted as if there were an implicit description of IBS with which each of them broadly agreed. This implicit description, if made explicit, could form a basis for diagnosis by logical implication. 6. This method of logical definition has general application in medicine and a set of defined cases could be used to establish entry criteria for multicentre trials of a previously ill-defined class.

An 69 platyrrhinen und catarrhinen Primaten-Spezies wurde der Molarengrößen-Gradient untersucht. Die Hauptvariation fand sich im relativen Anteil der Zahnkronenflächen der ersten und dritten Molaren (M1 und M3), weshalb das Größenverhältnis M1/M3 zur Kennzeichnung der Form und der relativen Größe der Molarenreihe herangezogen wurde. Der Beitrag des letzten Prämolaren (P4) zum gesamten postcaninen Kronenareal erwies sich als größer, wenn M3 relativ kleiner war. Das Verhältnis M1/M3 war bei arborealen Arten umgekehrt proportional zur Zeit, die jene Arten mit dem Fressen von Blättern verbringen. Das wird als eine Anpassung an eine Nahrung von kleinen, nicht-klebrigen Nahrungspartikeln in kleinen Mengen interpretiert. Terrestrische Arten haben erheblich kleinere M1/M3-Relationen. Die vergrößerte Zahnkronen-Oberfläche dürfte eine Anpassung gegen abrasive Nahrungskomponenten sein.

The seeds in fruits consumed by primates may be chewed and digested, swallowed and defecated intact, or separated from the flesh and spat out. We show by a combination of close field observations and experiments with caged animals, that long-tailed macaques (Macaca fascicularis) have a remarkably low threshold of 3–4 mm for swallowing seeds and also that wild macaques rarely break them. The seeds of 69% of the ripe fruit species eaten are spat out intact or cleaned outside the mouth and dropped. Seed-spitting significantly reduces the swallowed food bulk and may lessen the risk of releasing seed toxins during mastication. However, it requires that even small fruits are processed in the mouth one or a few at a time. We suggest that fruit storage in the cheek pouches of cercopithecine monkeys allows them to spit seeds individually without excessively slowing fruit intake while feeding on patchily distributed fruit. In contrast, Apes and New World monkeys apparently swallow and defecate most ripe seeds in their diet and colobine monkeys break and digest them, detoxifying seed defenses by bacterial fermentation.