A twenty year retrospective on the forest carbon dynamics in Russia

A regional forest carbon budget accounting technique based on carbon pools balance with incomes from growing woodstocks and losses from harvesting, fires and other disturbances have been developed. Forest carbon budgets of the Russian administrative units during 1988–2009 have been accounted. The carbon sink to Russian forests have increased from 80 Mt C × yr⁻¹ in 1988 to 230–240 Mt C × yr⁻¹ in late 2000s. This tendency is explained with the decline in harvesting, which have started in 1990s. European part of Russia was found to have higher areally averaged carbon sink compared with the Asian part. It have been associated with peculiar ways of wildfires governance in these two parts.     

Observations on Eye Movements in Amphibian Larvae

Observations have shown that amphibian larvae, contrary to what has been stated in the literature, have different kinds of eye movements. All of the anurans observed (Xenopus, Rana, Bufo, Hyperoleus and Bombina) have some kind of reflex eye movements effected through stimuli from the labyrinth organs as a response to movements of the body, while only Rana and Bufo have spontaneous scanning movements. Of the urodelians (Ambystoma and Triturus), larvae of Ambystoma have no observable eye movements, while Triturus larvae have reflex eye movements associated with movements of the neck, as well as spontaneous scanning movements; both kinds of movements differ from those seen in Anura.     

A Coupled Ecosystem-Climate Model for Predicting the Methane Concentration in the Archean Atmosphere

A simple coupled ecosystem-climate model is described that canpredict levels of atmospheric CH₄, CO₂, and H₂during the Late Archean, given observed constraints on Earth'ssurface temperature. We find that methanogenic bacteria shouldhave converted most of the available atmospheric H₂ intoCH₄, and that CH₄ may have been equal in importance to CO₂ as a greenhouse gas. Photolysis of this CH₄ may have produced a hydrocarbon smog layer that would have shielded the surface from solar UV radiation. Methanotrophic bacteria would have consumed some of the atmospheric CH₄,but they would have been incapable of reducing CH₄ to modern levels. The rise of O₂ around 2.3 Ga would have drastically reduced the atmospheric CH₄ concentrationand may thereby have triggered the Huronian glaciation.     

Bacteriolytic enzymes from the blood plasma of the sheep

Bacteriolytic factors from the blood plasma of healthy sheep have been studied. Three enzymes not described earlier in the literature have been identified and characterized. Two enzymes exhibit activity toward Escherichia coli and have molecular weights of 15 ± 2 kDa. The third enzyme that exhibits activity toward E. coli and Micrococcus luteus has a molecular weight of 34 ± 4 kDa. The kinetic parameters of bacterial lysis for all enzymes have been determined; in particular, optimal pH values for each of the substrates used have been found. For the identification of the enzymes, trypsinolysis and a mass-spectroscopic study of fragments have been carried out. The results were compared with the data on sheep proteins available in the Swiss-Prot, NCBI, and MSDB databases.     

Lysosomal Fragility induced by Prostaglandin F2α

PROSTAGLANDINS have been suggested as mediators of inflammatory reactions because they increase vascular permeability^1,2, are found in inflammatory exudates³, are released during antigen-antibody reactions⁴ and have leucotactic properties⁵. For this reason and because lysosomes have been assigned an important role in the pathogenesis of diverse tissue injury reactions⁶, we have studied the effect of prostaglandins on lysosomal fragility.     

Oxygen transfer characteristics of miniaturized bioreactor systems

Since their introduction in 2001 miniaturized bioreactor systems have made great advances in function and performance. In this article the dissolved oxygen (DO) transfer performance of submilliliter microbioreactors, and 1–10 mL minibioreactors was examined. Microbioreactors have reached k_La values of 460 h^?1, and are offering instrumentation and some functionality comparable to production systems, but at high throughput screening volumes. Minibioreactors, aside from one 1,440 h^?1 k_La system, have not offered as high rates of DO transfer, but have demonstrated superior integration with automated fluid handling systems. Microbioreactors have been typically limited to studies with E. coli, while minibioreactors have offered greater versatility in this regard. Further, mathematical relationships confirming the applicability of k_La measurements across all scales have been derived, and alternatives to fluorescence lifetime DO sensors have been evaluated. Finally, the influence on reactor performance of oxygen uptake rate (OUR), and the possibility of its real‐time measurement have been explored. Biotechnol. Bioeng. 2013; 110: 1005–1019. © 2012 Wiley Periodicals, Inc.     

Design and synthesis of 3-phenyltetrahydronaphthalenic derivatives as new selective MT2 melatoninergic ligands. Part II

Following our studies of the melatoninergic receptors, we have developed new tetrahydronaphthalenic derivatives of melatonin that have been tested as selective melatonin receptors ligands. Regarding the role of the phenyl substituent to obtain selective ligands, modulation of selectivity and activity have been achieved by modifications of the acyl group and substitutions on the phenyl ring. Ten of the seventeen evaluated derivatives have MT₂ receptor affinity similar to that of melatonin. Moreover, we have achieved remarkable MT₂ selectivity over MT₁ (selectivity >100) and have been able to further extend the RSA of the tetrahydrophthalenic series. However, the compounds presented here display partial agonist or antagonist behavior instead of full agonist.     

Molecular epidemiology of cryptosporidiosis: An update

Molecular tools have been developed to detect and differentiate Cryptosporidium at the species/genotype and subtype levels. These tools have been increasingly used in characterizing the transmission of Cryptosporidium spp. in humans and animals. Results of these molecular epidemiologic studies have led to better appreciation of the public health importance of Cryptosporidium species/genotypes in various animals and improved understanding of infection sources in humans. Geographic, seasonal and socioeconomic differences in the distribution of Cryptosporidium spp. in humans have been identified, and have been attributed to differences in infection sources and transmission routes. The transmission of C. parvum in humans is mostly anthroponotic in developing countries, with zoonotic infections play an important role in developed countries. Species of Cryptosporidium and subtype families of C. hominis have been shown to induce different clinical manifestations and have different potential to cause outbreaks. The wide use of a new generation of genotyping and subtyping tools in well designed epidemiologic studies should lead to a more in-depth understanding of the epidemiology of cryptosporidiosis in humans and animals.     

The proteins of nonoccluded Autographa californica nuclear polyhedrosis virus produced in an established cell line of Spodoptera frugiperda

Nonoccluded virions have been isolated from the extracellular fluid of cultured Spodoptera frugiperda cells that have been infected with Autographa californica nuclear polyhedrosis virus. By sucrose density gradient centrifugation, infectious virus particles have been obtained that exhibit densities of about 1.19 g/cm³. Using staining and autoradiographic techniques, about 35 polypeptides, including some high molecular weight proteins, have been detected by analysis of the virion proteins on sodium dodecyl sulfate-polyacrylamide slab gels (SDS-PAGE). Two major proteins of MW 65,000 and 42,000 have been found.     

HIV Infection and Sexual Risk among Men Who Have Sex with Men and Women (MSMW): A Systematic Review and Meta-Analysis

Objectives

To estimate the number of men who have sex with men and women who are HIV-positive in the United States, and to compare HIV prevalence rates between men who have sex with men and women, men who have sex with men only, and men who have sex with women exclusively.

Methods

Following PRISMA guidelines, we conducted a systematic review and meta-analysis of reports referencing HIV prevalence and men who have sex with men and women. We searched PubMed and Ovid PsycINFO for peer-reviewed, U.S.-based articles reporting on HIV prevalence among men who have sex with men and women. We conducted event rate, effect size, moderation and sensitivity analyses.

Results

We estimate that 1.0% of U.S. males are bisexually-behaving, and that 121,800 bisexually-behaving men are HIV-positive. Men who have sex with men and women are less than half as likely to be HIV-positive as men who have sex with men only (16.9% vs. 33.3%; OR = 0.41, 95% CI: 0.31, 0.54), but more than five times as likely to be HIV-positive as men who have sex with women exclusively (18.3% vs. 3.5%; OR = 5.71, 95% CI: 3.47, 9.39). They are less likely to engage in unprotected receptive anal intercourse than men who have sex with men only (15.9% vs. 35.0%; OR = 0.36, 95% CI: 0.28, 0.46). Men who have sex with men and women in samples with high racial/ethnic minority proportions had significantly higher HIV prevalence than their counterparts in low racial/ethnic minority samples.

Conclusions

This represents the first meta-analysis of HIV prevalence in the U.S. between men who have sex with men and women and men who have sex with men only. Data collection, research, and HIV prevention and care delivery specifically tailored to men who have sex with men and women are necessary to better quantify and ameliorate this population’s HIV burden.     

The Interplay of Angle Strain and Aromaticity: Molecular and Electronic Structures of [0n]Paracyclophanes

The belt-like polyphenylenes, [0_n]paracyclophanes, (n = 5 and 6), have been investigated using semi-empirical, ab initio and DFT methods. The molecular structure, rotational barrier on twisting a single phenyl ring and the aromatic character within each ring as well as in the whole molecule have been evaluated. [0₅]Paracyclophane is predicted to have a quinonoid structure. In contrast, the equatorial pentaphenyl fragment found in C₇₀ as well as the hexagons of the less strained [0₆]paracyclophane have benzenoid character. Approximate band structures have been derived for larger cycles of [0_n] paracyclophanes.Electronic Supplementary Material available.     

Pharmacophores of the dual acting α, β-blockers as deduced,from molecular dynamics simulations

The dual acting α, β-blockers have an important place in the management of hypertension. Molecular dynamics simulations have been carried out on all stereoisomers of seven dual acting α, β-blockers namely adimolol, amosulalol, bucindolol, carvedilol, labetalol, medroxalol and primidolol. Three families of conformations have been identified for the group of compounds. The pharmacophores for α and β-activity have been constructed for two of these families.     

RNA Synthesis in Chicken Erythrocytes

CHICKEN erythrocyte nuclei were reported not to synthesize RNA¹ and consequently have been used to study reactivation of nuclear synthesis^2–4. In some ducks, however, mature erythrocyte nuclei continue to synthesize some RNA^5–7 and we have found that the erythrocytes of adult chickens synthesize substantial amounts of RNA. We have found none in which the erythrocytes have no synthetic activity.     

Vanadium compounds as antiparasitic agents: An approach to their mechanisms of action

BackgroundParasitic infections are a public health problem since they have high morbidity and mortality worldwide. In parasitosis such as malaria, leishmaniasis and trypanosomiasis it is necessary to develop new compounds for their treatment since an increase in drug resistance and toxic effects have been observed. Therefore, the use of different compounds that couple vanadium in their structure and that have a broad spectrum against different parasites have been proposed experimentally.ObjectiveReport the mechanisms of action exerted by vanadium in different parasites.ConclusionIn this review, some of the targets that vanadium compounds have were identified and it was observed that they have a broad spectrum against different parasites, which represents an advance to continue investigating therapeutic options.     

Three-parameter lognormal distribution ubiquitously found in cDNA microarray data and its application to parametric data treatment

Background  

To cancel experimental variations, microarray data must be normalized prior to analysis. Where an appropriate model for statistical data distribution is available, a parametric method can normalize a group of data sets that have common distributions. Although such models have been proposed for microarray data, they have not always fit the distribution of real data and thus have been inappropriate for normalization. Consequently, microarray data in most cases have been normalized with non-parametric methods that adjust data in a pair-wise manner. However, data analysis and the integration of resultant knowledge among experiments have been difficult, since such normalization concepts lack a universal standard.     

Microbiological Standards and Handling Codes for Chilled and Frozen Foods. A Review

The usefulness of microbiological standards for frozen foods is now a controversy in the trade and scientific literature. Most reviewers have given arguments both for and against, and have concluded that they should be applied with great caution. Such standards have the advantage of putting questions of safety on a convenient numerical basis. Canadian workers have reported that promulgation of standards has invariably raised the hygienic level of the products controlled.

Bacteriological standards have often been associated with the question of safety to the consumer. Everyone recognizes that food poisoning bacteria are a potential danger in any food. But many have argued that the history of food poisoning outbreaks from frozen foods is excellent and that there is no need for standards; on the other hand, proponents of standards have pointed to the incomplete investigation and reporting of outbreaks, and have argued that there may be more outbreaks than we realize. They have pointed to laboratory studies that have shown grossly mishandled precooked frozen foods to be truly dangerous. Some have proposed that pathogens should be absent from foods; but others have questioned that a microbiological standard can accomplish this end. Some pathogens, such as Salmonella or Staphylococcus have been shown to be so ubiquitous that their presence in some commercial foods is unavoidable. Also, sampling and analytical methods have been described as inadequate to guarantee that pathogens present will be detected. Some have argued that control at the source is a better way—through inspections of the plant operation, by enforcement of handling codes, or by processing procedures such as pasteurization, which would be more certain to result in a pathogen-free food.

A most important part of any of the proposed standards is a “total count” of viable aerobic bacteria. English workers have found that foods causing poisoning outbreaks usually had total viable counts above 10 million per gram. On the other hand, these same workers found Salmonella on meats with very low total viable count. The assumption by many that low total count indicates safety has been shown to be not always true. Furthermore, high counts of nonpathogenic organisms, such as psychrophilic saprophytes would have no public health significance.

The relation between bacterial level and quality is open to less controversy. Some authorities have pointed to bacterial level as a measure of sanitation, adequacy of refrigeration, or speed of handling. Others have indicated that to determine which of these factors caused a high count would be impossible with only a total count on the product as a guide. Some investigators have said a high count affects flavor adversely before actual spoilage is evident, and this may be a factor in competition on today's market. It is well established that initial bacterial level will affect the shelf-life of a chilled product. Methods of analysis are more nearly adequate for counts than for pathogens, but they need improvement, and should be clearly specified as part of any bacteriological standard. Foods with high count could sometimes be brought into compliance merely by storing them for a sufficient period frozen, or by heating them slightly. This has been cited by some authors as a disadvantage of bacteriological standards.

The enterococci and the coliform group (except Escherichia coli) have been shown to be ubiquitous and therefore should not be used alone to indicate fecal contamination. Although E. coli has greater significance, its source should be determined each time it is found.

Various reviewers have expressed the need for caution in the application of standards. The principal precautionary arguments we have found are as follows:

1) A single set of microbiological standards should not be applied to foods as a miscellaneous group, such as “frozen foods” or “precooked foods.”

2) Microbiological standards should be applied first to the more hazardous types of foods on an individual basis, after sufficient data are accumulated on expected bacterial levels, with consideration of variations in composition, processing procedures, and time of frozen storage.

3) When standards are chosen, there should be a definite relation between the standard and the hazard against which it is meant to protect the public.

4) Methods of sampling and analysis should be carefully studied for reliability and reproducibility among laboratories, and chosen methods should be specified in detail as part of the standard.

5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis.

6) At first, the standard should be applied on a tentative basis to allow for voluntary compliance before becoming a strictly enforced regulation.

7) Microbiological standards will be expensive to enforce.

8) If standards are unwisely chosen they will not stand in courts of law.

     

SYSTEMATIC SIGNIFICANCE OF POLLEN NUCLEAR NUMBER IN EUPHORBIACEAE,TRIBE EUPHORBIEAE

Pollen nuclear number is determined in 139 species of 5 genera in the Euphorbieae, subtribe Euphorbiinae. The 111 new determinations are tabulated along with previous reports, and the results indicate that the distribution of binucleate (II) and trinucleate (III) pollen is strongly associated with the taxonomic groupings within the Euphorbieae. Although binucleate pollen is probably primitive within the tribe Euphorbieae, as suggested by the nuclear condition in Neoguillauminia, the situation in Euphorbia still requires further elucidation. Within Euphorbia, the morphologically most primitive species studied have III pollen despite the fact that II pollen is presumably the original condition for the subtribe Euphorbiinae. In Euphorbia, II pollen only is reported from nine sections and III pollen only from ten sections, while in four sections (Esula, Goniostema, Aphyllis, and Deuterocalli) both II and III pollen have been found. The New World species of Euphorbia nearly all have III pollen, whereas the vast majority of the African succulents have II pollen. The genera of New World origin, Chamaesyce and Pedilanthus, have III pollen, while the African genera Monadenium and Synadenium have II pollen. Independent derivations of III pollen from II pollen appear to have occurred in sections Goniostema, Aphyllis, and Deuterocalli (all of subg. Euphorbia). There is no evidence that reversals from III to II pollen have occurred.     

Hybrid clustering for microarray image analysis combining intensity and shape features

Background  

Image analysis is the first crucial step to obtain reliable results from microarray experiments. First, areas in the image belonging to single spots have to be identified. Then, those target areas have to be partitioned into foreground and background. Finally, two scalar values for the intensities have to be extracted. These goals have been tackled either by spot shape methods or intensity histogram methods, but it would be desirable to have hybrid algorithms which combine the advantages of both approaches.