bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculation of the electron transfer coupling matrix element in diabatic reactions
Authors: Shoji Mitsuo , Hanaoka Kyohei , Sato Akimasa , Kondo Daiki , Yang Moon Young , Kamiya Katsumasa , Shiraishi Kenji
Published: March 2012

Electron transfer coupling matrix elements, T values, are evaluated for three typical electron transfer (ET) systems: phenoxyl radical–phenol, DNA fragments, and copper‐containing nitrite reductase. Fragment charge difference method is improved by introducing the Pipek‐Mezey localization method. We found that T values are stably evaluated by using beta lowest unoccupied molecular orbitals, which are significantly more easily found compared to alpha ET orbitals. This technique is essential for metal‐containing ET systems. Redox‐active orbitals for the donor and accepter sites are derived by localizing the ET orbitals, and other related parameters such as the state energy gap and the localization index are also obtained. These orbitals and parameters are very useful to characterize their ET reactions. These practical techniques can be utilized for other general ET reactions. © 2012 Wiley Periodicals, Inc.
Chloroplastic NADPH‐dependent alkenal/one oxidoreductase contributes to the detoxification of reactive carbonyls produced under oxidative stress
Authors: Yamauchi Yasuo , Hasegawa Ayaka , Mizutani Masaharu , Sugimoto Yukihiro
Published: March 2012

Lipid peroxide‐derived reactive carbonyls (RCs) can cause serious damage to plant functions. A chloroplastic NADPH‐dependent alkenal/one oxidoreductase (AOR) detoxifies RCs, but its physiological significance remains unknown. In this study, we investigated the biological impacts of AOR using an AOR‐knock out Arabidopsis line (aor). Methyl viologen treatment, mainly to enhance photosystem (PS) I‐originated reactive oxygen species (ROS) production, caused more severe damage to aor than wild type (Col‐0). In contrast, the high light treatment used to enhance PSII‐originated ROS production resulted in no difference in PSII damage between Col‐0 and aor. In conclusion, AOR can contribute to detoxify stromal RCs produced under oxidative stress.
Background Rates of Acute Mountain Sickness-Like Symptoms at Low Altitude in Adolescents Using Lake Louise Score
Authors: Dallimore Jon , Foley Jo-ai , Valentine Peter
Published: March 2012

Objective

To record the incidence of symptoms consistent with a diagnosis of acute mountain sickness (AMS), using the Lake Louise questionnaire, in adolescents hiking at low altitude.

Methods

The study was carried out on a cohort of 123 adolescents during a 3-day trip on Dartmoor, UK, at an altitude of less than 500 m. The incidence of symptoms experienced was measured using the Lake Louise questionnaire, which was completed twice daily by each participant. An episode consistent with AMS, but in the low altitude setting, was defined as a score of 3 or more on the Lake Louise questionnaire in the presence of a headache.

Results

There were 59 boys and 64 girls in the study with an average age of 16.7 years. The response rate was 100%. A total of 59 episodes of scores consistent with AMS was recorded during the 3-day period. Forty-two of these episodes were reported by girls (71%). AMS scores between 3 and 8 were recorded, and the daily incidence rates of scores consistent with AMS but at low altitude were between 7.3% and 11.3%.

Conclusions

This study shows that adolescents at low altitude reported a background incidence of symptoms that at high altitude would lead to a diagnosis of AMS.
Mammoth tooth enamel growth rates inferred from stable isotope analysis and histology
Authors: Metcalfe Jessica Z. , Longstaffe Fred J.
Published: March 2012

Mammoth (Mammuthus sp.) teeth are relatively abundant in Quaternary deposits from Eurasia and North America, and their isotopic compositions can be used to reconstruct past seasonal patterns in precipitation, diet, and migration. Strategies for collecting and interpreting such data, however, are strongly dependent on growth rates, which can vary among species, individuals, and within teeth. In this study, we use histological and isotopic measurements to determine enamel growth rates for a Columbian mammoth (Mammuthus columbi) tooth in two directions. Using histology, the growth rate through the enamel thickness (ET; perpendicular to the height of the tooth) is estimated at 0.8 to 1.5 mm/yr. Isotopic sampling through the innermost 0.36 mm of the ET recovered less than half a period of variation (i.e., half an inferred year of growth), which is consistent with the histological estimate for ET growth rate. A combination of histological and isotopic measurements suggests that the enamel extension rate (growth in the height of the tooth) is 13–14 mm/yr. Knowledge of enamel growth rates should improve the design and interpretation of future isotopic studies of mammoth teeth. The combination of histological and isotopic measurements may also prove useful in determining growth rates for other extinct taxa.
HOW LAW PROTECTS DIGNITY
Authors: Waldron Jeremy
Published: March 2012

One way in which law protects dignity is by enforcing human rights provisions that explicitly prohibit degradation. But, as Lon Fuller and others have observed, law's connection with dignity is also deeper and more pervasive than this. In the way that its requirements are presented, in its procedures, in its sponsorship of argumentation, in treating people as equals, even in the distinctive way in which it makes use of coercion, law treats humans as dignified agents, capable of self-control, with a good sense of their own interests, and an ability to respond intelligently to its demands.
Obesity, inflammation and the immune system
Authors: de Heredia Fátima Pérez , Gómez-Martínez Sonia , Marcos Ascensión
Published: March 2012

Obesity shares with most chronic diseases the presence of an inflammatory component, which accounts for the development of metabolic disease and other associated health alterations. This inflammatory state is reflected in increased circulating levels of pro-inflammatory proteins, and it occurs not only in adults but also in adolescents and children. The chronic inflammatory response has its origin in the links existing between the adipose tissue and the immune system. Obesity, like other states of malnutrition, is known to impair the immune function, altering leucocyte counts as well as cell-mediated immune responses. In addition, evidence has arisen that an altered immune function contributes to the pathogenesis of obesity. This review attempts to briefly comment on the various plausible explanations that have been proposed for the phenomenon: (1) the obesity-associated increase in the production of leptin (pro-inflammatory) and the reduction in adiponectin (anti-inflammatory) seem to affect the activation of immune cells; (2) NEFA can induce inflammation through various mechanisms (such as modulation of adipokine production or activation of Toll-like receptors); (3) nutrient excess and adipocyte expansion trigger endoplasmic reticulum stress; and (4) hypoxia occurring in hypertrophied adipose tissue stimulates the expression of inflammatory genes and activates immune cells. Interestingly, data suggest a greater impact of visceral adipose tissue and central obesity, rather than total body fat, on the inflammatory process. In summary, there is a positive feedback loop between local inflammation in adipose tissue and altered immune response in obesity, both contributing to the development of related metabolic complications.
STABILITY OF SINGULAR JUMP-LINEAR SYSTEMS WITH A LARGE STATE SPACE: A TWO-TIME-SCALE APPROACH
Authors: NGUYEN DUNG TIEN , MAO XUERONG , YIN G. , YUAN CHENGGUI
Published: March 2012

This paper considers singular systems that involve both continuous dynamics and discrete events with the coefficients being modulated by a continuous-time Markov chain. The underlying systems have two distinct characteristics. First, the systems are singular, that is, characterized by a singular coefficient matrix. Second, the Markov chain of the modulating force has a large state space. We focus on stability of such hybrid singular systems. To carry out the analysis, we use a two-time-scale formulation, which is based on the rationale that, in a large-scale system, not all components or subsystems change at the same speed. To highlight the different rates of variation, we introduce a small parameter ε>0. Under suitable conditions, the system has a limit. We then use a perturbed Lyapunov function argument to show that if the limit system is stable then so is the original system in a suitable sense for ε small enough. This result presents a perspective on reduction of complexity from a stability point of view.
The Two Faces of Age Identity 1Action editor of this article was Dieter Ferring.
Authors: Weiss David , Lang Frieder R.
Published: March 2012

As people grow older they develop a sense of a dual age identity, referring to their age group and generation ( Weiss & Lang, 2009 ). Two studies (N1= 37, 60–85 years and N2= 104, 65–88 years of age) compared and contrasted older adults’ cognitive representations of two types of age cohort groups (age group vs. generation). Analyses reveal that age-group identity was more frequently associated with loss and decline, whereas generation identity was more frequently associated with positive characteristics and increased levels of agency. Findings also show that generation identity may – especially in later adulthood – serve as a means to compensate for loss. The self-protective function of the dual age identity and the dynamic and flexible nature of identification are further discussed.
Type I interferons in regulation of mucosal immunity
Authors: Mangan Niamh E , Fung Ka Yee
Published: March 2012

The mucosal system is the first line of defense against many pathogens. It is continuously exposed to dietary and microbial antigens, and thus the host must maintain a homeostatic environment between commensal microbiota and pathogenic infections. Following infections and inflammatory events, a rapid innate immune response is evoked to dampen the inflammatory processes. Type I interferons, a family of pleiotropic cytokines and major products of the innate immune response, have a key role in these early immune events at the mucosa, as reviewed here. With the emergence of new discoveries of immune cell types in mucosal tissues and their reactions to commensal and pathogenic organisms, we also review the opportunities for exciting research in this field.
Stable isotope-labelling analysis of the impact of inhibition of the mammalian target of rapamycin on protein synthesis
Authors: Huo Yilin , Iadevaia Valentina , Yao Zhong , Kelly Isabelle , Cosulich Sabina , Guichard Sylvie , Foster Leonard J. , Proud Christopher G.
Published: March 2012

mTORC1 [mTOR (mammalian target of rapamycin) complex 1] regulates diverse cell functions. mTORC1 controls the phosphorylation of several proteins involved in mRNA translation and the translation of specific mRNAs, including those containing a 5′-TOP (5′-terminal oligopyrimidine). To date, most of the proteins encoded by known 5′-TOP mRNAs are proteins involved in mRNA translation, such as ribosomal proteins and elongation factors. Rapamycin inhibits some mTORC1 functions, whereas mTOR-KIs (mTOR kinase inhibitors) interfere with all of them. mTOR-KIs inhibit overall protein synthesis more strongly than rapamycin. To study the effects of rapamycin or mTOR-KIs on synthesis of specific proteins, we applied pSILAC [pulsed SILAC (stable isotope-labelling with amino acids in cell culture)]. Our results reveal, first, that mTOR-KIs and rapamycin differentially affect the synthesis of many proteins. Secondly, mTOR-KIs inhibit the synthesis of proteins encoded by 5′-TOP mRNAs much more strongly than rapamycin does, revealing that these mRNAs are controlled by rapamycin-insensitive outputs from mTOR. Thirdly, the synthesis of certain other proteins shows a similar pattern of inhibition. Some of them appear to be encoded by ‘novel’ 5′-TOP mRNAs; they include proteins which, like known 5′-TOP mRNA-encoded proteins, are involved in protein synthesis, whereas others are enzymes involved in intermediary or anabolic metabolism. These results indicate that mTOR signalling may promote diverse biosynthetic processes through the translational up-regulation of specific mRNAs. Lastly, a SILAC-based approach revealed that, although rapamycin and mTOR-KIs have little effect on general protein stability, they stabilize proteins encoded by 5′-TOP mRNAs.
Pattern formation from consistent dynamical closures of uniaxial nematic liquid crystals
Authors: Híjar Humberto , de Hoyos Diego Marquina , Santamaría-Holek Iván
Published: March 2012

Pattern formation in uniaxial polymeric liquid crystals is studied for different dynamic closure approximations. Using the principles of mesoscopic non-equilibrium thermodynamics in a mean-field approach, we derive a Fokker-Planck equation for the single-particle non-homogeneous distribution function of particle orientations and the evolution equations for the second and fourth order orientational tensor parameters. Afterwards, two dynamic closure approximations are discussed, one of them considering the relaxation of the fourth order orientational parameter and leading to a novel expression for the free-energy like function in terms of the scalar order parameter. Considering the evolution equation of the density of the system and values of the interaction parameter for which isotropic and nematic phases coexist, our analysis predicts that patterns and traveling waves can be produced in lyotropic uniaxial nematics even in the absence of external driving.
A clinical data validated mathematical model of prostate cancer growth under intermittent androgen suppression therapy
Authors: Portz Travis , Kuang Yang , Nagy John D.
Published: March 2012

Prostate cancer is commonly treated by a form of hormone therapy called androgen suppression. This form of treatment, while successful at reducing the cancer cell population, adversely affects quality of life and typically leads to a recurrence of the cancer in an androgen-independent form. Intermittent androgen suppression aims to alleviate some of these adverse affects by cycling the patient on and off treatment. Clinical studies have suggested that intermittent therapy is capable of maintaining androgen dependence over multiple treatment cycles while increasing quality of life during off-treatment periods. This paper presents a mathematical model of prostate cancer to study the dynamics of androgen suppression therapy and the production of prostate-specific antigen (PSA), a clinical marker for prostate cancer. Preliminary models were based on the assumption of an androgen-independent (AI) cell population with constant net growth rate. These models gave poor accuracy when fitting clinical data during simulation. The final model presented hypothesizes an AI population with increased sensitivity to low levels of androgen. It also hypothesizes that PSA production is heavily dependent on androgen. The high level of accuracy in fitting clinical data with this model appears to confirm these hypotheses, which are also consistent with biological evidence.
The First Carbonyl-Substituted Derivative of [Mn2(CO)6(µ-pyS)2]
Authors: Rahman Md. Saifur , Sarker Jagodish C. , Ghosh Shishir , Kabir Shariff E.
Published: March 2012

Reaction of [Mn2(CO)6(μ-pyS)2] (1) with (Ph3P)2Ni(CO)2 at room temperature affords [Mn2(CO)5(PPh3)(μ-pyS)2] (3) which is the first carbonyl-substituted derivative of 1. A mononuclear complex fac-[Mn(CO)3(PPh3)(κ2-pyS)] (4) is also isolated as a minor product in this reaction. The formation of 3 allows us to propose a different mechanism operating in this reaction. A similar reaction between [Re2(CO)6(μ-pyS)2] (2) and (Ph3P)2Ni(CO)2 gives only mononuclear fac-[Re(CO)3(PPh3)(κ2-pyS)] (5). Both 4 and 5 undergo CO substitution to produce [M(CO)2(PPh3)2(κ2-pyS)] (6, M = Mn; 7, M = Re) when treated with (Ph3P)2Ni(CO)2 in boiling THF. Complex 3 also reacts with further (Ph3P)2Ni(CO)2 at room temperature to give 4 and 6. The molecular structures of 3 and 4 have been established by single crystal X-ray diffraction analyses.
Riboswitch control of Rho-dependent transcription termination
Authors: Hollands Kerry , Proshkin Sergey , Sklyarova Svetlana , Epshtein Vitaly , Mironov Alexander , Nudler Evgeny , Groisman Eduardo A.
Published: March 2012

Riboswitches are RNA sensors that regulate gene expression upon binding specific metabolites or ions. Bacterial riboswitches control gene expression primarily by promoting intrinsic transcription termination or by inhibiting translation initiation. We now report a third general mechanism of riboswitch action: governing the ability of the RNA-dependent helicase Rho to terminate transcription. We establish that Rho promotes transcription termination in the Mg
2+
-sensing
mgtA
riboswitch from
Salmonella enterica
serovar Typhimurium and the flavin mononucleotide-sensing
ribB
riboswitch from
Escherichia coli
when the corresponding riboswitch ligands are present. The Rho-specific inhibitor bicyclomycin enabled transcription of the coding regions at these two loci in bacteria experiencing repressing concentrations of the riboswitch ligands in vivo. A mutation in the
mgtA
leader that favors the “high Mg
2+
” conformation of the riboswitch promoted Rho-dependent transcription termination in vivo and in vitro and enhanced the ability of the RNA to stimulate Rho's ATPase activity in vitro. These effects were overcome by mutations in a C-rich region of the mRNA that is alternately folded at high and low Mg
2+
, suggesting a role for this region in regulating the activity of Rho. Our results reveal a potentially widespread mode of gene regulation whereby riboswitches dictate whether a protein effector can interact with the transcription machinery to prematurely terminate transcription.
Residual soil phosphorus as the missing piece in the global phosphorus crisis puzzle
Authors: Sattari Sheida Z. , Bouwman Alexander F. , Giller Ken E. , van Ittersum Martin K.
Published: March 2012

Phosphorus (P) is a finite and dwindling resource. Debate focuses on current production and use of phosphate rock rather than on the amounts of P required in the future to feed the world. We applied a two-pool soil P model to reproduce historical continental crop P uptake as a function of P inputs from fertilizer and manure and to estimate P requirements for crop production in 2050. The key feature is the consideration of the role of residual soil P in crop production. Model simulations closely fit historical P uptake for all continents. Cumulative inputs of P fertilizer and manure for the period 1965–2007 in Europe (1,115 kg⋅ha
−1
of cropland) grossly exceeded the cumulative P uptake by crops (360 kg⋅ha
−1
). Since the 1980s in much of Europe, P application rates have been reduced, and uptake continues to increase due to the supply of plant-available P from residual soil P pool. We estimate that between 2008 and 2050 a global cumulative P application of 700–790 kg⋅ha
−1
of cropland (in total 1,070–1,200 teragrams P) is required to achieve crop production according to the various Millennium Ecosystem Assessment scenarios [Alcamo J, Van Vuuren D, Cramer W (2006) Ecosystems and Human Well-Being: Scenarios, Vol 2, pp 279–354]. We estimate that average global P fertilizer use must change from the current 17.8 to 16.8–20.8 teragrams per year in 2050, which is up to 50% less than other estimates in the literature that ignore the role of residual soil P.
Spatial and temporal arrival patterns of Madagascar's vertebrate fauna explained by distance, ocean currents, and ancestor type
Authors: Samonds Karen E. , Godfrey Laurie R. , Ali Jason R. , Goodman Steven M. , Vences Miguel , Sutherland Michael R. , Irwin Mitchell T. , Krause David W.
Published: March 2012

How, when, and from where Madagascar's vertebrates arrived on the island is poorly known, and a comprehensive explanation for the distribution of its organisms has yet to emerge. We begin to break that impasse by analyzing vertebrate arrival patterns implied by currently existing taxa. For each of 81 clades, we compiled arrival date, source, and ancestor type (obligate freshwater, terrestrial, facultative swimmer, or volant). We analyzed changes in arrival rates, with and without adjusting for clade extinction. Probability of successful transoceanic dispersal is negatively correlated with distance traveled and influenced by ocean currents and ancestor type. Obligate rafters show a decrease in probability of successful transoceanic dispersal from the Paleocene onward, reaching the lowest levels after the mid-Miocene. This finding is consistent with a paleoceanographic model [Ali JR, Huber M (2010)
Nature
463:653–656] that predicts Early Cenozoic surface currents periodically conducive to rafting or swimming from Africa, followed by a reconfiguration to present-day flow 15–20 million years ago that significantly diminished the ability for transoceanic dispersal to Madagascar from the adjacent mainland.
Lantibiotics from
Geobacillus thermodenitrificans
Authors: Garg Neha , Tang Weixin , Goto Yuki , Nair Satish K. , van der Donk Wilfred A.
Published: March 2012

The lantibiotic nisin has been used as an effective food preservative to combat food-borne pathogens for over 40 y. Despite this successful use, nisin’s stability at pH 7 is limited. Herein, we describe a nisin analog encoded on the genome of the thermophilic bacterium
Geobacillus thermodenitrificans
NG80-2. This analog termed geobacillin I was obtained by heterologous expression in
Escherichia coli
and subsequent purification. Extensive NMR characterization demonstrated that geobacillin I contains seven thioether cross-links, two more than the five cross-links found in nisin and the most cross-links found in any lantibiotic to date. The antimicrobial spectrum of geobacillin I was generally similar to that of nisin A, with increased activity against
Streptococcus dysgalactiae
, one of the causative agents of bovine mastitis. Geobacillin I demonstrated increased stability compared to nisin A. In addition to geobacillin I, the genome of
G. thermodenitrificans
NG80-2 also contains a class II lantibiotic biosynthetic gene cluster. The corresponding compound was produced in
E. coli
, and has a ring topology different than that of any known lantibiotic as determined by tandem mass spectrometry. Interestingly, geobacillin II only demonstrated antimicrobial activity against
Bacillus
strains. Seven
Geobacillus
strains were screened for production of the geobacillins using whole-cell MALDI-MS and five were shown to produce geobacillin I, but none produced geobacillin II.
Structure of a hepatitis C virus RNA domain in complex with a translation inhibitor reveals a binding mode reminiscent of riboswitches
Authors: Dibrov Sergey M. , Ding Kejia , Brunn Nicholas D. , Parker Matthew A. , Bergdahl B. Mikael , Wyles David L. , Hermann Thomas
Published: March 2012

The internal ribosome entry site (IRES) in the hepatitis C virus (HCV) RNA genome is essential for the initiation of viral protein synthesis. IRES domains adopt well-defined folds that are potential targets for antiviral translation inhibitors. We have determined the three-dimensional structure of the IRES subdomain IIa in complex with a benzimidazole translation inhibitor at 2.2 Å resolution. Comparison to the structure of the unbound RNA in conjunction with studies of inhibitor binding to the target in solution demonstrate that the RNA undergoes a dramatic ligand-induced conformational adaptation to form a deep pocket that resembles the substrate binding sites in riboswitches. The presence of a well-defined ligand-binding pocket within the highly conserved IRES subdomain IIa holds promise for the development of unique anti-HCV drugs with a high barrier to resistance.
Partially collapsed cristobalite structure in the non molecular phase V in CO
2
Authors: Santoro Mario , Gorelli Federico A. , Bini Roberto , Haines Julien , Cambon Olivier , Levelut Claire , Montoya Javier A. , Scandolo Sandro
Published: March 2012

Non molecular CO
2
has been an important subject of study in high pressure physics and chemistry for the past decade opening up a unique area of carbon chemistry. The phase diagram of CO
2
includes several non molecular phases above 30 GPa. Among these, the first discovered was CO
2
-V which appeared silica-like. Theoretical studies suggested that the structure of CO
2
-V is related to that of β-cristobalite with tetrahedral carbon coordination similar to silicon in SiO
2
, but reported experimental structural studies have been controversial. We have investigated CO
2
-V obtained from molecular CO
2
at 40–50 GPa and T > 1500 K using synchrotron X-ray diffraction, optical spectroscopy, and computer simulations. The structure refined by the Rietveld method is a partially collapsed variant of SiO
2
β-cristobalite, space group

, in which the CO
4
tetrahedra are tilted by 38.4° about the
c
-axis. The existence of CO
4
tetrahedra (average O-C-O angle of 109.5°) is thus confirmed. The results add to the knowledge of carbon chemistry with mineral phases similar to SiO
2
and potential implications for Earth and planetary interiors.
Time-lapse two-color 3D imaging of live cells with doubled resolution using structured illumination
Authors: Fiolka Reto , Shao Lin , Rego E. Hesper , Davidson Michael W. , Gustafsson Mats G. L.
Published: March 2012

Previous implementations of structured-illumination microscopy (SIM) were slow or designed for one-color excitation, sacrificing two unique and extremely beneficial aspects of light microscopy: live-cell imaging in multiple colors. This is especially unfortunate because, among the resolution-extending techniques, SIM is an attractive choice for live-cell imaging; it requires no special fluorophores or high light intensities to achieve twice diffraction-limited resolution in three dimensions. Furthermore, its wide-field nature makes it light-efficient and decouples the acquisition speed from the size of the lateral field of view, meaning that high frame rates over large volumes are possible. Here, we report a previously undescribed SIM setup that is fast enough to record 3D two-color datasets of living whole cells. Using rapidly programmable liquid crystal devices and a flexible 2D grid pattern algorithm to switch between excitation wavelengths quickly, we show volume rates as high as 4 s in one color and 8.5 s in two colors over tens of time points. To demonstrate the capabilities of our microscope, we image a variety of biological structures, including mitochondria, clathrin-coated vesicles, and the actin cytoskeleton, in either HeLa cells or cultured neurons.
Finessing the fracture energy barrier in ballistic seed dispersal
Authors: Deegan Robert D.
Published: March 2012

Fracture is a highly dissipative process in which much of the stored elastic energy is consumed in the creation of new surfaces. Surprisingly, many plants use fracture to launch their seeds despite its seemingly prohibitive energy cost. Here we use
Impatiens glandulifera
as model case to study the impact of fracture on a plant’s throwing capacity.
I. glandulifera
launches its seeds with speeds up to 4 m/s using cracks to trigger an explosive release of stored elastic energy. We find that the seed pod is optimally designed to minimize the cost of fracture. These characteristics may account for its success at invading Europe and North America.
Cells test substrate rigidity by local contractions on submicrometer pillars
Authors: Ghassemi Saba , Meacci Giovanni , Liu Shuaimin , Gondarenko Alexander A. , Mathur Anurag , Roca-Cusachs Pere , Sheetz Michael P. , Hone James
Published: March 2012

Cell growth and differentiation are critically dependent upon matrix rigidity, yet many aspects of the cellular rigidity-sensing mechanism are not understood. Here, we analyze matrix forces after initial cell–matrix contact, when early rigidity-sensing events occur, using a series of elastomeric pillar arrays with dimensions extending to the submicron scale (2, 1, and 0.5 μm in diameter covering a range of stiffnesses). We observe that the cellular response is fundamentally different on micron-scale and submicron pillars. On 2-μm diameter pillars, adhesions form at the pillar periphery, forces are directed toward the center of the cell, and a constant maximum force is applied independent of stiffness. On 0.5-μm diameter pillars, adhesions form on the pillar tops, and local contractions between neighboring pillars are observed with a maximum displacement of ∼60 nm, independent of stiffness. Because mutants in rigidity sensing show no detectable displacement on 0.5-μm diameter pillars, there is a correlation between local contractions to 60 nm and rigidity sensing. Localization of myosin between submicron pillars demonstrates that submicron scale myosin filaments can cause these local contractions. Finally, submicron pillars can capture many details of cellular force generation that are missed on larger pillars and more closely mimic continuous surfaces.
Serotonin transporter polyadenylation polymorphism modulates the retention of fear extinction memory
Authors: Hartley Catherine A. , McKenna Morgan C. , Salman Rabia , Holmes Andrew , Casey B. J. , Phelps Elizabeth A. , Glatt Charles E.
Published: March 2012

Growing evidence suggests serotonin's role in anxiety and depression is mediated by its effects on learned fear associations. Pharmacological and genetic manipulations of serotonin signaling in mice alter the retention of fear extinction learning, which is inversely associated with anxious temperament in mice and humans. Here, we test whether genetic variation in serotonin signaling in the form of a common human serotonin transporter polyadenylation polymorphism (STPP/rs3813034) is associated with spontaneous fear recovery after extinction. We show that the risk allele of this polymorphism is associated with impaired retention of fear extinction memory and heightened anxiety and depressive symptoms. These STPP associations in humans mirror the phenotypic effects of serotonin transporter knockout in mice, highlighting the STPP as a potential genetic locus underlying interindividual differences in serotonin transporter function in humans. Furthermore, we show that the serotonin transporter polyadenylation profile associated with the STPP risk allele is altered through the chronic administration of fluoxetine, a treatment that also facilitates retention of extinction learning. The propensity to form persistent fear associations due to poor extinction recall may be an intermediate phenotype mediating the effects of genetic variation in serotonergic function on anxiety and depression. The consistency and specificity of these data across species provide robust support for this hypothesis and suggest that the little-studied STPP may be an important risk factor for mood and anxiety disorders in humans.
Soluble factors from T cells inhibiting X4 strains of HIV are a mixture of β chemokines and RNases
Authors: Cocchi Fiorenza , DeVico Anthony L. , Lu Wuyuan , Popovic Mikulas , Latinovic Olga , Sajadi Mohammad M. , Redfield Robert R. , Lafferty Mark K. , Galli Massimo , Garzino-Demo Alfredo , Gallo Robert C.
Published: March 2012

T-cell-derived soluble factors that inhibit both X4 and R5 HIV are recognized as important in controlling HIV. Whereas three β chemokines, regulated-on-activation normal T-cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1α, and MIP-1β, account for the suppression of R5 HIV by blockade of HIV entry, the major components responsible for the inhibition of X4 HIV strains have not been identified previously. We identify these factors primarily as a mixture of three β chemokines [macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC), and I-309] and two RNases (angiogenin and RNase 4) of lesser potency and show that in a clade B population, some correlate with clinical status and are produced by both CD4+and CD8+T cells (chemokines, angiogenin) or only by CD8+T cells (RNase 4). The antiviral mechanisms of these HIV X4-suppressive factors differ from those of the previously described HIV R5-suppressive β chemokines.
Old Frisian
Authors: Smith Laura Catharine
Published: March 2012

For a century, Old Frisian has largely remained in the shadows of its Germanic sister languages. While dictionaries, concordances, and grammars have been readily and widely available for learning and researching other Germanic languages such as Middle High German, Middle Low German and Middle English, whose timelines roughly correspond to that of Old Frisian, or their earlier counterparts, e.g., Old High German, Old Saxon and Old English, few materials have been available to scholars of Old Frisian. Moreover, as Siebunga (Boutkan & Siebunga 2005: vii) notes, “not even all Old Frisian manuscripts are available as text editions”1 making the production of comprehensive core research materials more difficult. Consequently, what materials there have been, e.g., von Richthofen (1840), Heuser (1903), Holthausen (1925), and Sjölin (1969), have typically not taken into consideration the full range of extant Old Frisian texts, or have focused on specific major dialects, e.g. Boutkan (1996), Buma (1954, 1961). This has left a gap in the materials available providing an opportunity for Old Frisian scholars to make substantial contributions to the field by filling these gaps.
Response of the South China Sea upper layer circulation to monsoon anomalies during 1997/1998 El Niño event
Authors: Lan Jian , Wang Yu , Bao Ying
Published: March 2012

One of the strongest El Niño events on record took place in the tropical Pacific in 1997–1998, causing remarkable changes in monsoon systems over the South China Sea (SCS) basin. This would induce prominent anomalies in the SCS upper layer circulation. The monsoon anomalies and the response of the upper layer circulation over the SCS during the 1997–1998 El Niño event are examined through data analysis and ocean numerical modeling, respectively. The winter monsoon and summer monsoon show southerly wind anomalies and northeasterly wind anomalies respectively during 1997/98 El Niño event, which was a reversal of the climatology. In contrast to climatology, the weakening of the winter monsoon does not change the upper layer circulation pattern, but causes a prominent change in the strength of the western boundary current. Corresponding to the anomalies of the summer monsoon, the upper layer circulation shows changes not only in magnitude, but also in structure from the climatology. The changes of the structure lie in the bifurcation of the western boundary current.
Distribution and interannual variation of winter phytoplankton blooms northwest of Luzon Islands from satellite observations
Authors: Zhao Hui , Sui Dandan , Xie Qiang , Han Guoqi , Wang Dongxiao , Chen Nancy , Tang DanLing
Published: March 2012

Phytoplankton blooms often occur in the offshore region northwest of Luzon Islands in winter. Using remote sensing data, including sea-surface temperature, monthly-mean mixed layer depth (MLD), wind speed (SP), and SeaWiFS-derived chlorophyll-a (Chl-a) data from September 1997 to February 2007, we investigate the spatial and interannual variation of the winter phytoplankton in the region along with in situ GTS (the Global Telecommunications System) XBT (Expendable Bathythermograph) data and climatological nitrate and temperature observations from World Ocean Atlas 2005. The results clearly show high winter phytoplankton biomass (i.e. Chl-a) and its interannual variation in the region. The lower Chl-a concentrations (∼0.2 mg m−3) appeared often in winters (e.g. 1997 and 1998) when there was weaker wind speed, Ekman pumping velocity (EPV) and entrainment velocity (EV), and shallower MLD; conversely higher Chl-a (>0.5 mg m−3) appeared in winters (e.g. 2001 and 2003) when there was higher subsurface temperature, stronger wind speed, EPV and EV, and deeper MLD. It is thought that wind-induced upwelling (Ekman pumping) and entrainment mixing may be important factors leading to the high winter Chl-a, and the wind speed and wind stress curl were good indicators of higher Chl-a; the positive correlation between subsurface temperature (and MLD) and Chl-a represented more warm water intrusion from the Northwest Pacific Ocean into the region in the higher Chl-a years.
Impacts of El Niño-Southern Oscillation and local sea surface temperature on moisture source in Asian-Australian monsoon region in boreal summer
Authors: Qiao Yunting , Huang Wei , Jian Maoqiu
Published: March 2012

El Niño-Southern Oscillation (ENSO) and local sea surface temperature (SST) have been regarded as the important factors influencing the precipitation, evaporation and circulation over the Asian-Australian monsoon (AAM) region. The moisture source is determined directly by precipitation and evaporation. This present paper studies the impacts of ENSO and local SST on moisture source in the AAM region during boreal summer. Relative roles of ENSO and local SST are also discussed by using the singular value decomposition (SVD) and conditional SVD (CSVD) methods. The authors identify one major coupled mode between the interannual variations of apparent moisture sink () and SST for the period 1979–2008. Spatial structure of the major mode exhibits two key regions of moisture source, one over the western-central southern Indian Ocean (SIO) where  is negative, and the other over the northwest and north side of Australia, where  is positive. In the corresponding map of SST, negative values are also seen in the former region, but are positive in the latter region. The interannual variation of moisture source in the AAM region has an outstanding positive correlation with the local SST. Furthermore, ENSO also has a remarkable correlation with the principle component (PC) of the first empirical orthogonal function (EOF) mode of . ENSO and local SST work cooperatively to determine the variations of moisture source in the AAM region.
Do poverty dynamics explain the shift to an informal private schooling system in the wake of free public primary education in Nairobi slums?
Authors: Oketch Moses , Mutisya Maurice , Sagwe Jackline
Published: March 2012

With the introduction of free primary education (FPE) in Kenya in 2003, it was expected that the burden on poor households in financing primary education would be reduced substantially. This in turn would increase enrolment in public schools and lead to universal primary education.
However, studies have shown that a considerable proportion of households in urban slums continue to enrol their children in pro-poor fee charging informal schools. The reasons presented in the available literature to explain this phenomenon of why poor slum-residing households bypass free
public education are varied and some are simply speculative. In this paper, we hypothesise that poverty dynamics can partly explain households' decisions on the type of school in which to enrol their children. The analysis is based on longitudinal data collected by the African Population and
Health Research Centre (APHRC) using urban demographic surveillance in two slums of Nairobi, Kenya. The data covers the period between 2005 and 2009 with a sample of 6965 pupils spread across 3763 households. Logistic regression methods are applied. The findings reveal that moving in and out
of poverty can affect the type of schooling decision a household makes, with one quarter of those moving out of poverty shifting schools. The findings demonstrate that there is both willingness and ability to pay by the slum residents that is driving the utilisation of the private schools.
The decisions are not random occurrences, but seem systematic and rational – parents want quality and affordability and a good number of those whose economic situation improved do not seem to believe the public schools, even under FPE, offers quality. The policy implication to be drawn
from these findings is that the private schools for the poor should not simply be dismissed as 'informal schools' because it seems they have some features which are attracting parents to choose them and leave the state system. Free primary education policy is being 'rejected' by a good number
of parents in the slums and this needs further investigation, as 'excess' demand as suggested in some research papers does not seem to be the only explanation.
Book Reviews
Authors: CLARKE Anji
Published: March 2012

Digital Media Contracts Alan Williams, Duncan Callow, and Andrew Lee Oxford, Oxford University Press, 2011, 381pp. 978‐0‐19‐956220‐6, £145 hbk
Project Transfer comes of age?
Authors: MITCHELL Alison , WINTER Elizabeth L.
Published: March 2012

The Transfer Code of Practice, first released in 2008, is a set of recommendations that establishes a baseline level of quality and performance in the event that a journal changes publisher. 2012 will see new developments from the Transfer Working Group, but there is still more work to be done to inform and educate all of the various constituencies involved in the journal transfer process.
Aqua(μ-cone-26,28-dibutoxy-25,27-bis{N-[5-(dimethylamino)naphthalene-1-sulfonyl]carbamoylmethoxy}-5,11,17,23-tetrakis(1,1-dimethylethyl)calix[4]arene(2−))disodium acetonitrile tetrasolvate
Authors: Dinake Pogisego , Prokhorova Polina E. , Talanov Vladimir S. , Butcher Ray J. , Talanova Galina G.
Published: March 2012

The structure of the title complex, [Na2(C80H98N4O10S2)(H2O)]·4CH3CN, obtained after crystallization from acetonitrile, contains two formula units in the asymmetric unit (Z′ = 2) and an estimated four molecules of acetonitrile per calixarene moiety. It is unusual for two Na+ions to occupy the lower rims of the cone calix[4]arene, as in this case, with one Na+ion forming two O→ Na+coordinate bonds with the two butoxy groups and four such bonds with the two N-dansyl carboxamide groups, forming six dative bonds between Na+and O. On the other hand, the other Na+ion forms only five O→Na+coordinate bonds on the far end of the calix[4]arene lower rim, bringing the two dansyl groups in close proximity with each other. There also appears to be an O→Na+coordination coming from a dangling water molecule. The structure contained both resolved and poorly resolved solvent molecules. The latter were treated using the SQUEEZE routine inPLATON[Spek (2009). Acta Cryst. D65, 148–155].
N-(2-Aminopyridin-3-yl)-4-methyl-N-(4-methylphenylsulfonyl)benzenesulfonamide
Authors: Taher Abu , Smith Vincent J.
Published: March 2012

The title compound, C19H19N3O4S2, was prepared by the reaction of 2,3-diaminopyridine with tosyl chloride in a mixture of dichloromethane–pyridine as solvent. In the crystal, molecules associateviapairs of N—H...N hydrogen bonds, forming a centrosymmetric eight-membered {...HNCN}2synthon. The dihedral angles between the aminopyridine ring and the tosyl benzene rings are 50.01 (6) and 32.01 (4)°.
7-Chloro-4-[(7-chloroquinolin-4-yl)sulfanyl]quinoline dihydrate
Authors: Wardell James L. , Tiekink Edward R. T.
Published: March 2012

In the title thioether dihydrate, C18H10Cl2N2S·2H2O, theS-bound quinolinyl residues are almost orthogonal, forming a dihedral angle of 72.36 (4)°. In the crystal, the four water molecules are connectedviaan eight-membered {...OH}4synthon with each of the four pendent water H atoms hydrogen bonded to a pyridine N atom to stabilize a three-dimensional architecture.
Dimethylammonium guanidinium naphthalene-1,5-disulfonate
Authors: Wei Bin
Published: March 2012

The asymmetric unit of the title salt, CH6N3+·C2H8N+·C10H6O6S22−, consists of one dimethylammonium cation, one guanidinium cation, and two half naphthalene-1,5-disulfonate anions, which lie on inversion centers. N—H...O hydrogen bonds link the cations and anions into layers parallel to theabplane. The layers have a sandwich-like structure, with the sulfonate groups and cations forming outer slices and the naphthalene ring systems inside.
5-Benzoyl-2-(1H-indol-3-yl)-4-(4-methylphenyl)-4,5-dihydrofuran-3-carbonitrile
Authors: Suresh J. , Vishnupriya R. , Gunasekaran P. , Perumal S. , Lakshman P. L. Nilantha
Published: March 2012

The furan ring in the title compound, C27H20N2O2, adopts a twisted conformation about thesp3—sp3bond. The molecular structure is stabilized by an intramolecular C—H...O interaction which generates anS(6) ring motif. The crystal packing is stabilized by N—H...O and C—H...O interactions generating centrosymmetricR22(18) andC(6) chain motifs, respectively. A weak C—H...π interaction is also observed.
3-Amino-1-(3,4-dimethoxyphenyl)-9,10-dihydrophenanthrene-2,4-dicarbonitrile
Authors: Asiri Abdullah M. , Faidallah Hassan M. , Alamry Khalid A. , Ng Seik Weng , Tiekink Edward R. T.
Published: March 2012

In the title compound, C24H19N3O2, the partially saturated ring adopts a distorted half-chair conformation with the methylene-C atom closest to the aminobenzene ring lying 0.664 (3) Å out of the plane defined by the five remaining atoms (r.m.s. deviation = 0.1429 Å. The dihedral angle [32.01 (10)°] between the benzene rings on either side of this ring indicates a significant fold in this part of the molecule. The dimethoxy-substituted benzene ring is almost orthogonal to the benzene ring to which it is attached [dihedral angle = 72.03 (9)°]. The molecule has been observed previously as the major component of a 1:19 co-crystal with 2-amino-4-(3,4-dimethoxyphenyl)-5,6-dihydrobenzo[ha]quinoline-3-carbonitrile [Asiriet al.(2011).Acta Cryst. E67, o2873–o2873]. Supramolecular chains with base vector [201] are formed in the crystal structureviaN—H...O hydrogen bonds between the amino H atoms of one molecule interacting with the methoxy O atoms of a neighbouring molecule. The chains are linked into a three-dimensional architecture by C—H...π interactions.
Poly[bis(μ-purin-9-ido-κ2N7:N9)zinc]
Authors: Cadiau A. , Adil K.
Published: March 2012

In the title compound, [Zn(C5H3N4)2], the ZnIIcation is in a nearly regular tetrahedral coordination by purinate ligands. Each purinate ligand chelates two ZnIIcations through two imidazole N atoms of the purinate anion ligand, leading to the formation of a three-dimensional network.
(8-Aminoquinoline-κ2N,N′)bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato-κ2O,O′)cobalt(II)
Authors: Harding David J. , Sertphon Darunee , Harding Phimphaka
Published: March 2012

In the title compound, [Co(C5HF6O2)2(C9H8N2)], the CoIIcentre exhibits a pseudooctahedral coordination geometry, comprising two N-atom donors from the bidentate aminoquinoline ligand and four O-atom donor atoms from two bidentate chelating 1,1,1,5,5,5-hexafluoropentane-2,4-dionate ligands. In the crystal, molecules are linkedviapairs of N—H...O hydrogen bonds, forming inversion dimers. These dimers are further connected through π–π interactions between neighbouring quinoline rings [centroid–centroid distance = 3.472 (2) Å], and stack along thecaxis.
N,N-Dimethyl-4-[(E)-2-(3,6,7-tribromo-9-butyl-9H-carbazol-2-yl)ethenyl]aniline
Authors: Kumar Sushil , Thomas K. R. Justin , Ng Seik Weng , Tiekink Edward R. T.
Published: March 2012

In the title molecule, C26H25Br3N2, a dihedral angle of 6.15 (10)° is present between the carbazole and benzene ring systems with anEconformation about the C=C bond [1.335 (4) Å]. The butyl group is almost perpendicular to the carbazole plane [C—N—C—C torsion angle = −98.7 (3)°]. In the crystal, supramolecular double chains along [-7,18,-16] are formedviaC—H...Br and π–π interactions [centroid(carbazole five-membered ring)...centroid(carbazole six-membered ring) distance = 3.6333 (13) Å].
(E)-N-Benzylideneadamantan-1-amine
Authors: Jin Xu-Dong , Yin Xue-Yue , Wang Hai-Bo , Chang Xiao-Hong , Jin Yue-Hong
Published: March 2012

In the title compound, C17H21N, the dihedral angle between the benzene ring and the imine group (—N=) is 5.1 (4)°. In the adamantane group, the C—C—C bond angles range from 107.88 (19) to 111.33 (17)°. Only weak van der Waals interactions contribute to the contribute to the packing of the molecules in the crystal..