Book of the Occurrences of the Times to Jeshurun in the Land of Israel - Ḳorot ha-ʻitim li-Yeshurun be-ʾErets Yiśraʾel

This work was authored by Menahem Mendel me-Kaminitz (an ancestor of one of the current translators David Cook) following his first attempt to settle in the Land of Israel in 1834

Randomised controlled trial comparing rubber band ligation with stapled haemorrhoidopexy for Grade II circumferential haemorrhoids : Long-term results

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Predicting gene expression in the human malaria parasite Plasmodium falciparum using histone modification, nucleosome positioning, and 3D localization features.

Empirical evidence suggests that the malaria parasite Plasmodium falciparum employs a broad range of mechanisms to regulate gene transcription throughout the organism's complex life cycle. To better understand this regulatory machinery, we assembled a rich collection of genomic and epigenomic data sets, including information about transcription factor (TF) binding motifs, patterns of covalent histone modifications, nucleosome occupancy, GC content, and global 3D genome architecture. We used these data to train machine learning models to discriminate between high-expression and low-expression genes, focusing on three distinct stages of the red blood cell phase of the Plasmodium life cycle. Our results highlight the importance of histone modifications and 3D chromatin architecture in Plasmodium transcriptional regulation and suggest that AP2 transcription factors may play a limited regulatory role, perhaps operating in conjunction with epigenetic factors

A catchment-based study of endocrine disruption in surface waters: multivariate evaluation of the health of a sentinel fish species exposed to sewage treatment works effluent

Summary of the results in the context of EDCAT 5 project aims: 1. By comparing appropriate biomarkers in fish sampled from STW-impacted sites and control sites during the pre-remediation period, to determine whether there was evidence for any effects that might be attributed to the presence of estrogenic (or androgenic, or anti-androgenic/-estrogenic) endocrine disrupting chemicals in the former. This aim was addressed by measuring concentrations of the estrogen-dependent yolk protein precursor vitellogenin, and the androgen-dependent nest glue spiggin in male and female sticklebacks. In addition histological examination of the gonadal structure of fish captured at the impacted and non-impacted sites was employed to seek evidence of overt alterations in reproductive physiology of the fish. For a subset of matched samples from the two rivers, the relative induction of hepatic choriogenin mRNA, a biomarker of estrogen exposure, was measured. Conclusions: Chemistry data provided by EDCAT3&4 showed that estrogenicity of the effluent was low prior to remediation and lower still following installation of the GAC plant. No evidence of overt estrogenic effects was detected in male sticklebacks in the Ray, VTG and ChG levels were similar in males from both rivers. Nor was there any evidence of alterations in spiggin concentrations in the kidneys of males from the Ray compared to the Ock. However, VTG concentrations in female sticklebacks from the Ray were increased following the STW upgrade as were hepatic ChG transcript levels, and kidney spiggin concentrations. No changes in these elements of the reproductive system were observed in females from the Ock across the same time periods. Chemical analysis of the effluent indicated that prior to installation of the GAC plant substantial concentrations of anti-androgenic chemicals were present, together with a wide range of other organics. Concentrations of these were much reduced following the plant upgrade. It is reasonable to suppose that the changes observed in the female reproductive endocrine system following the upgrade were related to the removal of some or all of this complex mixture of chemicals. The absence of effects in males may be related to the balance between exogenous and endogenous signals, or to the specificity of effects exerted by the chemicals present. No intersex fish were detected from either river. A significant bias in favour of females was detected in the stickleback populations in both rivers suggesting a factor associated with life-history of the fish, rather than contaminant burden, was responsible. 2. By comparing appropriate biomarkers in fish sampled from STW-impacted sites and control sites during the pre-remediation period, to determine whether there was evidence for any effects that might be attributed to the presence of “conventionally” toxic chemicals. This was addressed by measurement of the activity of a key Phase I transforming enzyme in the liver of fish, either using direct enzymatic assay (EROD) or by quantifying the levels of expression of the corresponding gene (CYP1A). Conclusions: EROD activity was significantly greater in fish from the Ray than the Ock in two samples collected prior to the installation of the GAC plant (2006, 2007) and this likely reflects the differential contaminant loading in the two rivers. A single sample following the commissioning of the GAC plant (2008) indicated that EROD activity had increased among fish from the Ock while that in fish from the Ray remained unchanged. While a delayed recovery of this biomarker in fish from the Ray may be expected depending on the route of exposure (direct via water or indirect via contaminated food) the reasons for elevated EROD activity in fish from the Ock/Childrey Brook are not immediately evident. Provision of a full data set for Cyp1A expression awaits the repeat of the assay. When this is complete the factors underlying the EROD findings may become clear. 3. To determine whether the adaptive capacity and energetic status of fish varied between the STW-impacted and non-impacted sites. This was addressed by measurement of indicators of stress (whole-body corticosteroid levels), metabolic status (whole-body glucose levels) and anabolic activity (RNA:DNA ratios). Conclusions: The data provide no evidence that the stress response of fish captured in the Ray prior to installation of the GAC plant was modified by exposure to the effluent. However, large variations in whole-body corticosteroid and glucose concentrations in fish from both rivers, with clear trends over time, were closely linked to perturbations in the river flow regime. Whether there was interaction between environmental and chemical factors in determining corticosteroid and glucose status is difficult to discern but it seems likely that variation in these indicators of the stress axis was driven primarily by environmental factors. The RNA:DNA ratios were closely linked with seasonal change in temperature and closely matched observed patterns of weight and length gain in stickleback populations in the two rivers. The longer growth period enjoyed by fish in the Ray was clearly evident. For both rivers, mean anabolic activity was greater during 2008 than 2007 and it seems likely that this is related to adverse effects associated with the periods of extreme flow change observed on both rivers in 2007. 4. To assess whether there were differences in population size and structure between STW-impacted and non-impacted sites. This was addressed by comparison of key somatic measures, in particular frequency distributions for fork length. Conclusions: Because of the extreme patchiness of the distribution of stickleback populations in both rivers accurate abundance estimates were not obtained. However, the catch per unit effort across the life of the project was similar for both rivers. While population size, and age structure (both rivers hosted annual populations), appeared to be similar fish in the Ray were overall larger than those from the Ock, and spawned earlier. The differences in growth and timing of spawning between the rivers were likely to have been associated with the Rodbourne STW effluent. Downstream of the discharge on the Ray water temperatures were consistently 2 – 3oC above those of the Ock. This temperature difference, in combination with the introduction of additional nutrients into the river which is likely to have affected the availaibility of food, probably accounts for the different growth profile among the sticklebacks in the two rivers. However, over and above this difference, there was a significant increase in size of sticklebacks in the Ray between the matched pre- and post-remediation periods in the Ray while no change in size of the fish in the Ock occurred during the same period. Similarly, the RNA:DNA ratio was higher in fish from the Ock during 2007 but greater in fish from the Ray during 2008. Taken together, these observations suggest that there was an improvement in the status of the fish in the Ray following the commissioning of the GAC plant, while the population in the Ock remained relatively stable. It is reasonable to suppose that this may be linked to the reduction of the chemical load entering the Ray at Rodbourne following the installation of the GAC plant. The Ray is “cleaner” now than was the case prior to remediation but remains nutrient rich and several degrees warmer than the Ock, this combination of factors providing fish in the Ray with greater scope for growth relative to populations in the Ock

Clustering of solutions in the random satisfiability problem

Using elementary rigorous methods we prove the existence of a clustered phase in the random $K$-SAT problem, for $K\geq 8$. In this phase the solutions are grouped into clusters which are far away from each other. The results are in agreement with previous predictions of the cavity method and give a rigorous confirmation to one of its main building blocks. It can be generalized to other systems of both physical and computational interest.Comment: 4 pages, 1 figur

Origin and significance of 'dispersed facies' basal ice: Svínafellsjökull, Iceland

Dispersed facies basal ice - massive (i.e. structureless) ice with dispersed debris aggregates - is present at the margins of many glaciers and, as a product of internal glacial processes, has the potential to provide important information about the mechanisms of glacier flow and the nature of the subglacial environment. The origin of dispersed facies is poorly understood, with several hypotheses having been advanced for its formation, and there is disagreement as to whether it is largely a sedimentary or a tectonic feature. We test these established hypotheses at the temperate glacier Svfnafellsjokull, Iceland, and find that none fully account for dispersed facies characteristics at this location. Instead, dispersed facies physical, sedimentological and stable-isotope (5180, 8D) characteristics favour a predominantly tectonic origin that we suggest comprises the regelation and straininduced metamorphism of debris-rich basal ice that has been entrained into an englacial position by tectonic processes operating at the base of an icefall. Further thickening of the resultant dispersed facies may also occur tectonically as a result of ice flow against the reverse bed slope of a terminal overdeepening. Lack of efficient subglacial drainage in the region of the overdeepening may limit basal melting and thus favour basal ice preservation, including the preservation of dispersed facies. Despite the relatively low sediment content of dispersed facies (~1.6% by volume), its thickness (up to 25 m) and ubiquity at Svfnafellsjokull results in a significant contribution to annual sediment discharge (1635-3270 m3 a"1) that is ~6.5 times that contributed by debris-rich stratified facies basal ice

Preparing ground states of quantum many-body systems on a quantum computer

Preparing the ground state of a system of interacting classical particles is an NP-hard problem. Thus, there is in general no better algorithm to solve this problem than exhaustively going through all N configurations of the system to determine the one with lowest energy, requiring a running time proportional to N. A quantum computer, if it could be built, could solve this problem in time sqrt(N). Here, we present a powerful extension of this result to the case of interacting quantum particles, demonstrating that a quantum computer can prepare the ground state of a quantum system as efficiently as it does for classical systems.Comment: 7 pages, 1 figur

Modifying the Einstein Equations off the Constraint Hypersuface

A new technique is presented for modifying the Einstein evolution equations off the constraint hypersurface. With this approach the evolution equations for the constraints can be specified freely. The equations of motion for the gravitational field variables are modified by the addition of terms that are linear and nonlocal in the constraints. These terms are obtained from solutions of the linearized Einstein constraints.Comment: 4 pages, 1 figure, uses REVTe

Randomised trial of glutamine, selenium, or both, to supplement parenteral nutrition for critically ill patients

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