Split Off Research Articles

READING THE NEANDERTHAL CODE

ANOTHER DAY, ANOTHER GENOME project. But this one is definitely not your average genome project. In fact, the species in question has been extinct for thousands of years. Last month, Max Planck Institute for Evolutionary Anthropology, in Leipzig, Germany, and 454 Life Sciences, in Branford, Conn., announced their plans to sequence the Neanderthal genome. The researchers, led by evolutionary anthropologist Svante Paabo, hope to fill in the gaps in our understanding of human evolution by looking at our cousins, the Neanderthals. We need to compare ourselves to our most recent common ancestor, which happens to be extinct, Paabo said at a webcast press conference announcing the project. Among living species, humans share their nearest common ancestor with chimpanzees, which branched off evolutionarily at least 5 million years ago. Neanderthals split off much more recently, somewhere around a half-million years ago. The first Neanderthal fossils were discovered 150 years ago in Germany's Neander Valley. Most...

Sex therapy as a humanistic enterprise

Contemporary sexology is fragmented, with the new sexuality studies almost completely split off from the new sexual therapies. Clinical sexology research and practice are in danger of being captured by commercial interests, chiefly the global pharmaceutical industry. One solution to both of these intellectual problems comes from an examination of the all-but-forgotten history of humanistic sexology in the 1970s. It may be that the political involvement, research creativity, body – mind approaches, and respect for sexual diversity that emerge from this history can offer some directions for contemporary sexologists. The New View of Women's Sexual Problems, an educational campaign dedicated to challenging the post-Viagra medicalisation of sexual problems, incorporates some of these humanistic elements in a way that offers some new training directions.

Tensile fracture behavior of a biodegradable polymer, poly(lactic acid)

The stable and dynamic fracture behavior of a biodegradable polymer, poly(lactic acid) (PLA), was investigated using single-edge-cracked tensile specimens. To study the dynamic effect of brittle facture, the specimens were pin-loaded using a special jig that allowed them to split and fly off in the loaded direction after fracture. The non-elastic effect of viscoelastic and plastic deformations was also measured using an optical high-speed extensometer, which consisted of an optical fiber and a position-sensing detector (PSD). For the stable and dynamic fracture process, external work applied to the specimen and its fracture surface was partitioned into U s and U d, and A s and A d, respectively. The energy release rate, G s, for stable crack growth was determined using U s/ A s. The kinetic and non-elastic energies were measured and subtracted from U d to evaluate the fracture energy for the dynamic process, E f. The dynamic energy release rate, G f, was then determined as E f/ A d. G d was also obtained as U d/ A d to correlate with G s and G f, and the results are discussed.

Projective modules over smooth real affine varieties

Let X = Spec(A) be a smooth affine variety of dimension n ≥ 2 over a field k and P be a projective A-module of rank n. A result of Murthy ([Mu], Theorem 3.8) says that if k is an algebraically closed field and if the top Chern class Cn(P) in CH0(X) is zero, then P splits off a free summand of rank 1 (i.e. P A⊕ Q). We note that over any base field, the vanishing of the top Chern class is a necessary condition for P to split off a free summand of rank 1. However, as is shown by the example of the tangent bundle of an even dimensional real sphere, this condition is not sufficient. In view of these examples, it is of interest to explore whether one can classify examples of projective modules over smooth real varieties which have the property that the top Chern class of the projective module vanishes but the projective module does not split off a free summand of rank one. More precisely we ask the following:

Method for preparing single-stranded DNA templates for Pyrosequencing using vector ligation and universal biotinylated primers

In Pyrosequencing, the addition of nucleotides to a primer–template hybrid is monitored by enzymatic conversion of chemical energy into detectable light. The technique yields both qualitative and quantitative sequence information because the chemical energy is released by a stoichiometric split off of pyrophosphates from incorporated deoxynucleotide triphosphates and a defined nucleotide dispensation order is given. Because Pyrosequencing works best if single-stranded DNA templates are used, template generation usually requires PCR with a target-specific biotinylated primer and a subsequent purification involving interaction of the biotin label with immobilized streptavidin. To circumvent the need for numerous and expensive template-specific biotinylated primers, we developed a method that uses the ligation of amplified DNA fragments into a plasmid vector, thereby facilitating subsequent PCR using a universal vector-specific biotinylated primer. This approach allows easy and straightforward isolation of single-stranded templates of any PCR product. As a proof of principle, we used the method for genotyping two single-nucleotide polymorphisms in the human genes CARD15 and A2M and for characterization of four multisite variations in the human DEFB104 gene.

A Fast Edge-Splitting Algorithm in Edge-Weighted Graphs

Let H be a graph with a designated vertex s, where edges are weighted by nonnegative reals. Splitting edges e = {u,s} and e' = {s,v} at s is an operation that reduces the weight of each of e and e' by a real δ > 0 while increasing the weight of edge {u,v} by δ. It is known that all edges incident to s can be split off while preserving the edge-connectivity of H and that such a complete splitting is used to solve many connectivity problems. In this paper, we give an O(mn + n2 log n) time algorithm for finding a complete splitting in a graph with n vertices and m edges.

A Universal Type IA Topoisomerase Fold

A class of enzymes, called DNA topoisomerases, is responsible for controlling the topological state of cellular DNA. Among these, type IA topoisomerases form a vast family that is present in all living organisms, including higher eukaryotes, in which they play important roles in genome stability. The known 3D structures of three of these enzymes indicate that they share a common toroidal architecture. We previously showed that the toroidal structure could be split off from the core enzyme of Thermotoga maritima topoisomerase I by limited proteolysis. This structure is produced by the association of two tandemly repeated elementary folds in a head-to-tail orientation. By using a combination of structural and sequence data analysis, we show that the elementary fold of about 150 amino acid residues, referred to as the topofold, is likely to be present in the whole topoisomerase IA family. Within each enzyme, the successive topofolds share two conserved sequence motifs located at the base of the ring, and referred to as the MI and MII motifs. However, the overall sequences of the folds have largely diverged. By contrast, secondary and tertiary structures appear remarkably conserved. We suggest that this twofold repeat has evolved by gene duplication/fusion from an ancestral topofold.

Falling Forever: The Price of Chronic Shock

Manifestations of chronic shock and annihilation anxiety—including autistic defenses, chaotic relationships, disorganized attachment, split–off affective states, and vulnerability to disintegration—exist side by side with apparent ego strength and high functioning, even in nonabused patients. Chronic shock stemming from uncontained distress and failed dependency during childhood can persist throughout the lifespan, creating ripples of dysfunction that mask as character distortion and contribute to therapeutic impasse. Patients rely on omnipotent defenses to provide a sense of “having skin” in the face of the fear of breakdown, striving to avoid vulnerability, and trying to insulate themselves from shock experience. Although the relinquishment of autistic defenses and subsequent integration of disowned affect states are overwhelming and painful, patients can emerge from this process with significant shifts in intrapsychic, interpersonal, and existential/spiritual functioning. Clinical material from one psychodynamic psychotherapy group tracks the group process and growth trajectories of seven group members struggling with chronic shock. The ability to recognize subtle dissociative states is a valuable tool in the repertoire of the group psychotherapist.

"Knowledge in Passing:" Reflexive Anthropology and Religious Awareness

In this article, I outline affinities between a Roman Catholic way of thinking in which I was raised, and local Muslim shape of thought which I encountered during fieldwork. Thus, I engage with some of recent literature on issues of reflexivity in ethnographic practice. But I go beyond a reflexive critique of my fieldwork and analysis, to argue that this critique can actually engender substantive comparisons between particular kinds of Catholicism and Islam. In my conclusions, I gather together my reflections to reconsider connection between religious beliefs of ethnographer and his capacity to make statements about religion of his informants. I end by sketching ontological possibilities that emerge. In Anthropology and Autobiography, Judith Okely argues that ethnographer must through specificity of anthropologist's self in order to contextualize and transcend (Okely 1992:2). The tendency to split off or exclude self results from a canonical stress on neutral, impersonal, scientific work (Okely 1992:9-10). She cites approvingly Jean-Paul Dumont's argument for a movement back and forth [in ethnographic investigation] between and consciousness (Okely 1992:13). Narrowing her discussion to possible forms which autobiographical analysis might take, she argues for necessity of considering ethnographer's relations with others being studied. She writes of embodiment of fieldwork experiences, their physicality, but she does make point that the reflexive knowledge of fieldwork is acquired not only from an examination of outside categories, but also from more intangible inner experience (Okely 1992:16-17). Her main concern appears to be that fieldworker interrogate nature of his or her interactions with host community. In contrast, this paper is concerned with ways in which fieldworker's religious categories, developed from childhood through young manhood, subsequently affected his relations with Muslim society which he studied-and more importantly, his analysis of it. I stopped participating fully in Catholic belief and ritual seven years before beginning fieldwork. Nevertheless, I argue that Catholicism established a strange familiarity with Muslim village in northern Nigeria where I did my fieldwork. More pointedly, my analytical reflections in writing my dissertation were shaped by memories of forcible images during fieldwork. Both memories and reflections were selective, because they drew, without my realizing it, on thought processes and deep perspectives which I attribute here to a Catholic education and home life. I propose that there are strange resonances between worlds of Roman Catholicism and Islam, which led me to sympathize with Islam at a very deep level. Childhood and Youth My of Catholicism was heavily affected by age in which I grew up, nature of bond between my parents, and mode of livelihood of my father. My father was an American soldier posted every few years to a new and distant place. A cradle Catholic, his religious practice had been somewhat desultory until his of hell in Second World War led him to belief that there must be some ultimate good-or, at least, that we ought to search for it through prayer, examination of conscience and sacraments of Church. My mother was English, but of French origin, hence Catholic. Though of very different backgrounds, they shared strong bonds of religion, humor, and a mutual of war. I was born in 1948 at a time when many men had emerged from recent war and its anguish with silent elation of a certain kind of religious discovery (see biographies of period, for example, of convert monk Thomas Merton and of many military men who tried monastic life). The world which we inhabited changed every few years with move of family to a new army posting, but very architecture of churches, presence of priests and nuns, and Catholic books were a continuing thread. …

Purification and properties of a coagulant thrombin-like enzyme from the venom of Bothrops leucurus

A thrombin-like enzyme from Bothrops leucurus venom, named leucurobin (leuc), was purified by gel filtration, affinity and ion exchange chromatographies. Physicochemical studies indicated that the purified enzyme is a 35 kDa monomeric glycoprotein on SDS-PAGE under reducing conditions, which decreased to 29 kDa after deglycosylation with N-glycosidase F (PNGase F). The amino acid sequence of leuc was determined by automated sequencing of the intact native protein and peptides produced by digestion of the S-pyridyl-ethylated protein with trypsin. The protein sequence exhibits significant similarities with other serine proteases reported from snake venoms, and contains two potential sites of N-linked glycosylation. The proteinase split off fibrinopeptide A (FPA) rapidly from human fibrinogen; however, only negligible traces of fibrinopeptide B (FPB) were observed. In addition, the enzyme released the N-terminal peptide (Mr=4572) containing the first 42 residues from the Bbeta-chain. Leuc could neither activate factor XIII nor release kinins from heat-treated bovine plasma. Its specific clotting activity was equivalent to 198 NIH thrombin U/mg on human fibrinogen. Kinetic properties of leuc were determined using representative chromogenic substrates. The enzyme evoked the gyroxin syndrome when injected into the tail veins of mice at levels of 0.143 microg/g mouse. The inhibitory effects of PMSF and benzamidine on the amidolytic activity suggest that leuc is a serine proteinase, and inhibition by beta-mercaptoethanol revealed the important role of the disulfide bonds in the stabilization of the native structure. Antibothropic serum, SBTI and EDTA had little or no effect on its amidolytic activity. However, the clotting effect of the enzyme was strongly inhibited by antibothropic serum. A Dixon plot showed that the hydrolysis of Bz-L-Arg-pNA by leuc was competitively inhibited by benzamidine (Ki=1.61+/-0.25 mM).

Study on the thermal degradation of polyoxymethylene by thermogravimetry–Fourier transform infrared spectroscopy (TG–FTIR)

AbstractThermal degradation behaviors of polyoxymethylene in nitrogen are systematically studied by Thermogravimetry–Fourier Transform infrared spectroscopy (TG–FTIR). Two primary degradation mechanisms are definitely determined by the production of formaldehyde and carbon monoxide collected from successive FTIR spectrum. First, POM tends to split off formaldehyde starting at unstable chain‐ends, then random chain scission occurs at elevated temperature, and several related reactions possibly occur during the degradation process. The results prove that during the degradation, formaldehyde is the predominant product, and therefore polyether as the stabilizers used can greatly improve the degradation temperature of POM in the initial stage, and consequently effectively inhibit the thermal degradation of POM. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3085–3092, 2006

The Female Face of God

Locating the influence of modernity on gender in the ancient world of the Near East, this discussion of women’s spirituality traces the history of the idea that the monotheistic god of Judaism, Islam, and Christianity was originally both male and female. Paralleling the myths of the Hebrews and their pagan neighbors, which developed around fertility cults prominently featuring women, the author argues that patriarchal reforms ushered in during the 7th century B.C.E. forced worship of the female face of god underground. Thus split off from mainstream worship, the old fertility cults nonetheless continued to flourish in secret mystical communities. Here, god’s female aspect was worshiped symbolically as “Shekhinah”, the “bride of Yahweh” — now metaphorically identified with the exiled community of Israel. Focusing on the sexually charged and gendered mystical imagery resulting from the reformist prohibitions against goddess worship, the discussion pinpoints its sublimation in mystical contemplative practices from the Deuteronomic period to the present. Locating the influence of modernity on gender in the ancient world of the Near East, this discussion of women’s spirituality traces the history of the idea that the monotheistic god of Judaism, Islam, and Christianity was originally both male and female. Paralleling the myths of the Hebrews and their pagan neighbors, which developed around fertility cults prominently featuring women, the author argues that patriarchal reforms ushered in during the 7th century B.C.E. forced worship of the female face of god underground. Thus split off from mainstream worship, the old fertility cults nonetheless continued to flourish in secret mystical communities. Here, god’s female aspect was worshiped symbolically as “Shekhinah”, the “bride of Yahweh”—now metaphorically identified with the exiled community of Israel. Forcusing on the sexually charged and gendered mystical imagery resulting from the reformist prohibitions against goddess worship, the discussion pinpoints its sublimation in mystical contemplative practices from the Deuteronomic period to the present.

Periodic Alignment of Silicon Dot Fabricated by Linearly Polarized Nd:YAG Pulse Laser

AbstractPeriodically aligned submicron Si dots were fabricated by only irradiating linearly polarized Nd:YAG pulse laser to the amorphous silicon (a-Si) thin film deposited on silicon dioxide (SiO2) film. Interference between the incident beam and the scattered surface wave leads to the spatial periodicity of beam energy density distribution on the surface of the irradiated samples. The a-Si thin film was melted by laser beam, and then, the molten thin Si film was split and condensed due to its surface tensile according to the periodic energy density distribution. The polycrystalline Si (poly-Si) fine lines were formed periodically. After the first irradiation, the sample was rotated by 90o, and the laser beam was irradiated. The periodic energy density distribution was generated on the Si fine lines. Then, the lines were split off and condensed according to the periodic energy density distribution, and the periodically aligned submicron Si dots were fabricated on the SiO2 film.

Mechanistic investigations of the methanol-to-olefin (MTO) process on acidic zeolite catalysts by in situ solid-state NMR spectroscopy

This paper reviews mechanistic investigations of the methanol-to-olefin (MTO) process by in situ solid-state NMR spectroscopy, mainly performed under continuous-flow and stopped-flow conditions. During methanol conversion on the silicoaluminophosphate H-SAPO-34 under continuous-flow conditions, a hydrocarbon-pool consisting of a mixture of C 6–C 12 olefins and aromatics was found. The hydrocarbon-pool mechanism was verified as the dominating route in the MTO process under steady-state conditions. By in situ MAS NMR experiments under continuous-flow conditions it could be demonstrated that methanol molecules are added to the hydrocarbon-pool and light olefins are split off as reaction products. The reactivity of surface methoxy groups in the MTO process were evidenced by the reaction with different probe molecules. By the new developed in situ MAS NMR-UV/vis technique, the initial formation of the hydrocarbon-pool during the induction period was investigated.

Curved quantum waveguides in uniform magnetic fields

A theoretical study of a planar electronic waveguide with a uniformly curved section in the perpendicular homogeneous magnetic field $\mathbf{B}$ is presented within the envelope function approximation. Utilizing analytical solutions in each part of the waveguide, exact expressions are derived for the scattering and reflection matrices and for the transcendental equation defining bound-state energies. It is shown that in the magnetic field a propagation threshold in the continuously curved channel is always smaller than its counterpart for the straight arm which means that bound states in the uniform magnetic field always exist. Their energies do not depend on the direction of the field, and at high magnetic intensities they approach the lowest Landau level. For the transport in the fundamental mode an interaction of a quasibound level split off from the higher-lying threshold as a result of the bend, with its degenerate continuum counterpart, causes a dip in the transmission. In the magnetic field, contrary to the field-free case, conductance in the minimum ${G}_{\mathit{min}}$, generally, ceases to be zero. It is shown that growing magnetic fields cause ${G}_{\mathit{min}}$ to saturate to $2{e}^{2}∕h$ which means that a quasibound level formed as a result of the bend is completely dissolved by the increasing $\mathbf{B}$; however, this transformation is very different for the different bend angles and radii. In particular, quasibound states of the fundamental propagation mode survive stronger fields for the smaller bend angles which is explained by the larger total magnetic flux through the curved section where these levels are formed. Since a magnetic length ${l}_{B}={(\ensuremath{\hbar}∕eB)}^{1∕2}$ is inversely proportional to the square root of $B$, states for the waveguide with a smaller radius also survive stronger fields, and their asymptotic approach to the dissolution possesses nonmonotonic ${G}_{\mathit{min}}$ dependence on the magnetic field with minimum conductance again reaching zero for some special values of $B$. Vortex structure of the currents flowing in the waveguide near the resonance is strongly affected by the field. In particular, small magnetic intensities change zero-field vortices in the straight arms into the magnetic antivortices which correspond to the interacting with each other surface currents flowing along opposite walls of the channel. Increasing the magnetic field suppresses the formation of the vortices pushing currents to the outer (inner) walls in the straight (bent) section. For fields larger than the saturation magnetic intensity, the only consequence of the bend is a strong surface current near the convex wall of the bend, and the electronic flow along the junctions between straight and curved parts.

Outside race, inside gender: A good enough “holding environment” in counselling and psychotherapy

While there is general agreement that race, culture and ethnicity are critical variables in counselling and psychotherapy, very little is known about how they are psychologically constructed. Race, for example, in its current usage is far too broad and indefinite to be clinically useful. However, race and racism does enter the therapy room, and if left unexplored or disavowed can, in a pervasive way, dislocate and alienate clients and create much anxiety in therapists. Although there appears to be no consensus theoretically, scientifically or clinically on its meaning, race is still an important issue to explore in therapy. Yet, to engage with race and racism in therapy is theoretically and practically difficult, and could be made impossible by some counselling approaches. This paper examines how race can be explored in the therapy room. For clients who are afraid of talking about race and racism gender appears to be a safe place to communicate unwanted and split off feelings. Race then becomes more acceptable because the discourse of gender provides it with a particular set of vocabularies, epistemologies and linguistic resonance that can provide a good enough holding environment, offering both client and therapist with an opportunity to explore through the gendering of race other complex interpersonal issues.

Intra-valence-band mixing in strain-compensatedSiGequantum wells

We explore the midinfrared absorption of strain-compensated $p\text{\ensuremath{-}}{\mathrm{Si}}_{0.2}{\mathrm{Ge}}_{0.8}∕\mathrm{Si}$ quantum wells for various well thicknesses and temperatures. Owing to the large band offset due to the large bi-axial strain contrast between the wells and barriers, the intersubband transitions energies from the ground state to the excited heavy hole (HH), light hole (LH), and split-off (SO) hole states up to $\ensuremath{\sim}0.5\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ are resolved. When HH2 is within $\ensuremath{\sim}30\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ of LH1 or SO1 a partial transfer of the HH1-HH2 oscillator strength to the HH1-LH1 or HH1-SO1 transitions is observed, which is otherwise forbidden for light polarized perpendicular to the plane of the wells. This is a clear sign of mixing between the HH and LH or SO states. A large temperature induced broadening of HH1-HH2 transition peak is observed for narrow wells indicating nonparabolic dispersion of the HH2 states due to the mixing with the LH/SO continuum. We found that the observations are in good agreement with the six-band $\mathbf{k}∙\mathbf{p}$ theory. A possible role of many-body effects in the temperature-induced negative peak shift is discussed.

Evolution of geometric and electronic structure at theBi∕Ag(001)interface

Growth of Bi on the Ag(001) surface at $300\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ has been studied. Low energy electron diffraction and scanning tunneling microscopy were used to reveal that the $\mathrm{Bi}∕\mathrm{Ag}(001)$ surface forms four distinct ordered structures upon deposition of Bi at $300\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, $c(2\ifmmode\times\else\texttimes\fi{}2)$, $c(4\ifmmode\times\else\texttimes\fi{}4)$, $p(4\ifmmode\times\else\texttimes\fi{}4)\text{\ensuremath{-}}p4g$, and $(\sqrt{5}\ifmmode\times\else\texttimes\fi{}\sqrt{5})R26.6\ifmmode^\circ\else\textdegree\fi{}$ phases. A reversible phase transition from the $c(2\ifmmode\times\else\texttimes\fi{}2)$ structure to $c(n\ifmmode\times\else\texttimes\fi{}4)$, with $n=6--7$, upon cooling to $\ensuremath{\sim}240\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ was observed. Another phase transition from the $c(4\ifmmode\times\else\texttimes\fi{}4)$ structure to $c(2\ifmmode\times\else\texttimes\fi{}2)$ upon heating was also observed. Angle-resolved photoelectron spectroscopy was used to study the evolution of the valence electronic structure. Several Bi derived surface states were observed along the high symmetry directions. A surface resonance band, split off from the Ag $5sp$ states, was observed along the edge of the Ag bulk band projected onto the (001) surface. This band is similar to that observed on $\mathrm{In}∕\mathrm{Cu}(001)$ and is considered to have a major contribution from the substrate states. $\mathrm{Bi}\text{\ensuremath{-}}6p$ derived bands, showing narrow bandwidth and periodicities coincident with the surface structure, were also observed.

Pamela A Gilbert, Mapping the Victorian social body, Studies in the Long Nineteenth Century, State University of New York Press, 2004, pp. xxii, 245, illus., US$65.00 (hardback 0-7914-6025-8), US$21.95 (paperback 0-7914-6026-6).

Pamela A Gilbert, Mapping the Victorian social body, Studies in the Long Nineteenth Century, State University of New York Press, 2004, pp. xxii, 245, illus., US21.95 (paperback 0-7914-6026-6). - Volume 49 Issue 4

Theoretical Study of the Heptamethylbenzenium Ion. Intramolecular Isomerizations and C2, C3, C4 Alkene Elimination

Recent experimental work on the methanol-to-hydrocarbons (MTH) reaction in zeolite H-Beta suggests that the heptamethylbenzenium (heptaMB+) cation is an important intermediate. We have carried out quantum chemical calculations to investigate intramolecular isomerization reactions and eliminations of small alkenes such as ethene, propene, and isobutene from heptaMB+ isomers. Two types of reaction paths have been investigated for the alkene formation: One starting with an initial ring contraction, and one starting with an initial ring expansion of the heptaMB+ ion. The reaction starting with an initial ring contraction leads to a bicyclic species that may split off propene or, after further isomerizations, isobutene. Expansion to a seven-membered ring may, via further isomerizations, lead to formation of ethyl and isopropyl groups that may in turn be split off as ethene and propene. The calculations have been carried out at the B3LYP/cc-pVTZ//B3LYP/6-311G(d,p) level of theory with zero point energy corrections. Comparisons with experimental data are made where possible.