Immobilization Of Factors Research Articles

A corollary study to substantiate the therapeutic role of receptor from Shigella flexneri in mitigating the sperm immobilization factor-mediated negative influences on mouse spermatozoa: a molecular mimicry-based approach.

Context Sperm immobilization factor (SIF) isolated from Staphylococcus aureus has been implicated earlier in the laboratory in infertility due to its negative impact on sperm function. Moreover, SIF was found to bind not only to human and mouse spermatozoa but also to several bacteria. Among the array of bacteria, we selected Shigella flexneri to investigate if it shares antigenic determinants with spermatozoa. Aim The study aimed to delineate receptors from S. flexneri that imitate the sperm receptor in binding SIF, to assess its therapeutic role in SIF-mediated sperm impairment. Methods Sperm immobilization binding receptor (SBR) from S. flexneri (SF-SBR) was isolated via ultrasonication and 4M NaCl treatment, purified via chromatography and its molecular weight was estimated. The ability of SF-SBR to counteract SIF-induced sperm impairment was assessed in vitro . Further analysis included isothermal titration calorimetry and fourier-transform infrared spectroscopy to quantify the interaction of SIF and SF-SBR. Key results SF-SBR ameliorated the sperm parameters adversely affected by SIF. It also interfered with the binding of fluorescein isothiocyanate-labelled SIF to spermatozoa and bacteria. The SIF and SF-SBR interaction showed favourable thermodynamics with an entropy of 28.12J/molK and free energy of -18.48kJ/mol, supporting the concept of mimicry. Conclusions The study confirmed that SF-SBR shares an epitope with the receptor on mouse spermatozoa, affirming the presence of molecular mimicry between spermatozoa and S. flexneri . Implications These findings indicate that SF-SBR can potentially be used to counteract the effects of SIF on spermatozoa, hinting at novel therapeutic approaches for treating infertility caused by microbial sperm immobilization factors.

Enhanced Hydrogen Peroxide Decomposition in a Continuous-Flow Reactor over Immobilized Catalase with PAES-C.

Due to the specificity, high efficiency, and gentleness of enzyme catalysis, the industrial utilization of enzymes has attracted more and more attention. Immobilized enzymes can be recovered/recycled easily compared to their free forms. The primary benefit of immobilization is protection of the enzymes from harsh environmental conditions (e.g., elevated temperatures, extreme pH values, etc.). In this paper, catalase was successfully immobilized in a poly(aryl ether sulfone) carrier (PAES-C) with tunable pore structure as well as carboxylic acid side chains. Moreover, immobilization factors like temperature, time, and free-enzyme dosage were optimized to maximize the value of the carrier and enzyme. Compared with free enzyme, the immobilized-enzyme exhibited higher enzymatic activity (188.75 U g-1, at 30 °C and pH 7) and better thermal stability (at 60 °C). The adsorption capacity of enzyme protein per unit mass carrier was 4.685 mg. Hydrogen peroxide decomposition carried out in a continuous-flow reactor was selected as a model reaction to investigate the performance of immobilized catalase. Immobilized-enzymes showed a higher conversion rate (90% at 8 mL/min, 1 h and 0.2 g) compared to intermittent operation. In addition, PAES-C has been synthesized using dichlorodiphenyl sulfone and the renewable resource bisphenolic acid, which meets the requirements of green chemistry. These results suggest that PAES-C as a carrier for immobilized catalase could improve the catalytic activity and stability of catalase, simplify the separation of enzymes, and exhibit good stability and reusability.

An experimental study to decipher the implications of antigenic sharing between Proteus mirabilis and mouse spermatozoa in eliciting an antisperm immune response: A potential culprit in immune infertility

The present study aims to investigate the antigenic cross reactivity between the receptor from Proteus mirabilis and spermatozoa against a common sperm immobilization factor, SIF, by calorimetric and competitive inhibition studies, and the immunogenicity of this receptor to evoke the formation of antisperm antibodies and their subsequent role in fertility outcome. The sperm binding receptor from Proteus mirabilis (PM-SBR) was extracted from ultrasonicated cell debris by treating it for 12 h at 37°C with 1 M NaCl. After being purified by gel permeation chromatography, its molecular weight as determined by SDS-PAGE was observed to be ≈ 47 kDa. The detrimental impacts of Sperm immobilizing factor (SIF) on spermatozoa viz. motility, viability, and morphology were mitigated when SIF was preincubated with various concentrations of PM-SBR. Using isothermal titration calorimetry, the entropy of the SIF-PM-SBR interaction was found to be -18.31 kJ/mol, whereas the free energy was 28.4 J/mol K. FTIR analysis was used to evaluate the binding interactions between PM-SBR and SIF. In addition, mice that were administered antibodies against PM-SBR were unable to conceive, in contrast to mice that were administered Phosphate buffer saline (PBS) or pre-immunization serum as controls. In light of this, we may conclude that anti-PM-SBR antibodies act as anti-sperm antibodies. Our work found that molecular mimicry between Proteus mirabilis and spermatozoa may cause antisperm immune reactivity. As a result of an immunological response to PM-SBR, infected individuals may produce antibodies against an epitope similar to one found on spermatozoa which helps in developing new strategies for managing autoimmune responses and infertility.

Preparation and Characterization of a Novel Morphosis of Dextran and Its Derivatization with Polyethyleneimine.

Dextran, a variant of α-glucan with a significant proportion of α-(1,6) bonds, exhibits remarkable solubility in water. Nonetheless, the precipitation of dextran has been observed in injection vials during storage. The present study aimed to establish a technique for generating insoluble dextran and analyze its structural properties. Additionally, the potential for positively ionizing IS-dextran with polyethyleneimine was explored, with the ultimate objective of utilizing IS-dextran-PEI as a promising support for enzyme immobilization. As a result, IS-dextran was obtained by the process of slow evaporation with an average molecular weight of 6555 Da and a yield exceeding 60%. The calculated crystallinity of IS-dextran, which reaches 93.62%, is indicative of its irregular and dense structure, thereby accounting for its water insolubility. Furthermore, positive charge modification of IS-dextran, coupled with the incorporation of epichlorohydrin, resulted in all zeta potentials of IS-dextran-PEIs exceeding 30 mV, making it a promising supporting factor for enzyme immobilization.

Foreign Direct Investment in Neoclassical Theory of International Trade: A Conceptual Weak Spot

This article analyses the role of foreign direct investment (FDI) in neoclassical theory of trade with a focus on the relocation of production into low wage countries. The conceptual analysis shows that FDI not only constitutes a weak spot in comparative advantage theory, but also that the latter is incompatible with efficiency-seeking FDI—with significant implications for policy. In Ricardian and Heckscher-Ohlin models of trade, FDI is ruled out via the assumption of factor immobility. In models in which factor immobility is relaxed, the closest FDI comes to is a generic reference to capital imports and exports, which affect factor endowments and, therefore, comparative advantage. Due to the assumption that input factors are determined by wage-rental ratios, this leads to the condition that firms operating in advanced economies must produce more labor-intensively, if investing in facilities in low-wage countries. Efficiency and market-seeking FDI, which combines productive, capital-intensive modes of production with cheap labor to exploit unit labor cost differentials, is a theoretical and mathematical impossibility in this framework. This conceptual weakness questions the validity of conventional approaches to development policy, which largely rely on market liberalization and free capital mobility.

Effects of Functionalized Materials and Bacterial Metabolites on Quality Indicators in Composts.

The addition of functionalized materials (biochar, zeolite, and diatomite) and lyophilized metabolic products of Pseudomonas sp. and Bacillus subtilis to composted biomass may bring many technological and environmental benefits. In this study, we verify the effects of biochar, zeolite Na-P1 (Na6Si10Al6O32·12 H2O), diatomite (SiO2_nH2O), and bacterial metabolites on the composting of biomass prepared from poultry litter, corn straw, grass, leonardite, and brown coal. The experimental design included the following treatments: C-biomass without the addition of functionalized materials and bacterial metabolites, CB-biomass with the addition of biochar, CBM-biomass with the addition of biochar and bacterial metabolites, CZ-biomass with the addition of zeolite, CZM-biomass with the addition of zeolite and bacterial metabolites, CD-biomass with the addition of diatomite, and CDM-biomass with the addition of diatomite and bacterial metabolites. Composts were analyzed for enzymatic and respiratory activities, mobility of heavy metals, and the presence of parasites. The results of this study revealed that, among the analyzed functionalized materials, the addition of diatomite to the composted biomass (CD and CDM) resulted in the most effective immobilization of Cd, Zn, Pb, and Cu. Zinc immobilization factors (IFHM) for diatomite-amended composts averaged 30%. For copper, each functionalized material was found to enhance mobilization of the element in bioavailable forms; similar observations were made for lead, except for the compost to which biochar and bacterial metabolites were added (CBM). The determined values of biochemical indicators proved the different effects of the applied functionalized materials and bacterial metabolites on the microbial communities colonizing individual composts. The dehydrogenase activity (DhA) was lower in all combinations as compared with the control, indicating an intensification of the rate of processes in the studied composts. The highest basal respiration (BR) and substrate-induced respiration (SIR) activities were determined in composts with the addition of bacterial metabolites (CBM, CZM, and CDM). The addition of functionalized materials completely inactivated Eimeria sp. in all combinations. In the case of Capillaria sp., complete inactivation was recorded for the combination with zeolite as well as biochar and diatomite without bacterial metabolites (CB, CZ, and CD).

Fungal necromass presents a high potential for Mercury immobilization in soil

Past industrial activities have generated many contaminated lands from which Mercury (Hg) escapes, primarily by volatilization. Current phytomanagement techniques aim to limit Hg dispersion by increasing its stabilization in soil. Although soil fungi represent a source of Hg emission associated with biovolatilization mechanisms, there is limited knowledge about how dead fungal residues (i.e., fungal necromass) interact with soil Hg. This study determined the Hg biosorption potential of fungal necromass and the chemical drivers of passive Hg binding with dead mycelia. Fungal necromass was incubated under field conditions with contrasting chemical properties at a well-characterized Hg phytomanagement experimental site in France. After four months of incubation in soil, fungal residues passively accumulated substantial quantities of Hg in their recalcitrant fractions ranging from 400 to 4500 μg Hg/kg. In addition, infrared spectroscopy revealed that lipid compounds explained the amount of Hg biosorption to fungal necromass. Based on these findings, we propose that fungal necromass is likely an important factor in Hg immobilization in soil.

Can e-commerce platforms build the resilience of brick-and-mortar businesses to the COVID-19 shock? An empirical analysis in the Chinese retail industry

We proposed a research model that examined the differences between the contributions of large, third-party e-commerce platforms and self-operated e-commerce platforms to businesses’ resilience to the COVID-19 shock. The difference-in-differences approach was employed to analyze a substantial sample of Chinese retailers. The study found that (1) under the baseline condition, the large, third-party e-commerce platforms built significant resilience for the brick-and-mortar businesses, (2) resource constraints induced by factor immobility weakened the contribution of large, third-party e-commerce platforms to the businesses’ resilience in regions of severe shock, and (3) the physical retailers’ self-operated EC platforms built resilience in regions of severe shock.

Marginal lands as an important potential to produce biohydrogen

One of the promising approaches for hydrogen production is agricultural biomass crops conversion, which is a renewable-based clean and abundant resource. The main objective of the current study is to assess the contribution of soil beneficial microbes in improving salt tolerance along with the evaluation of possible hydrogen production from sorghum plant biomass. High salinity concentrations in soil stimulate plant roots to enhance the plant desire for symbiosis and association with vesicular-arbuscular mycorrhizal fungi (VAM). Among the VAM species, G.mosseae is one of the significant and effective VAM species, which contribute to plant salinity resistance by expanding leaf salt potential and accumulating nutrients leaves in comparison to other soil microorganisms in plants. Morphological characters of these plants show a higher biomass production during saline conditions up to 2000 kg/ha. Biomass production in the specific alternative thermochemical and biological processes are suggested and finally, gasification processes were chosen as the optimal method which can be practically applied to produce hydrogen from sorghum plants. By producing 10,000 kg biomass in three harvesting periods of Sorghum, almost 3000 kg biomass for bio-hydrogen production can be obtained. This could be an appropriate resource for obtaining biofuels, particularly bio-hydrogen from 3 million hectares of unbearable or poor quality lands in a country such as Turkey by producing 9 million tons of Hydrogen. Obtained data gives an overview of these technologies for hydrogen production from biomass yielding to 28.2 gH2/100 g biomass or 33.17 to 44.26 (gH2). Producing green hydrogen from plants biomass is relatively cheaper, compared to chemo-industrial methods. Achieving the immobilization factors in bioprocesses for microorganisms is obtained in this study. Consequently, hydrogen productivity of the bioprocess can be enhanced by using porous support materials which provide high biomass holding capacity and help better gas retrieve in the process.

Evaluation of Antifertility Effects of Sperm Immobilization Factor from Escherichia coli on Male Mice

Earlier in our laboratory, sperm immobilization factor (SIF) isolated from Escherichia coli has shown admirable contraceptive efficacy in female mice and thus generated interest in evaluating the same as a potential candidate for male contraception. Keeping this in mind, the present study was aimed at exploitation of SIF as contraceptive agent in male mouse model after intra testis administration. For this, Balb/c mice were administered with different concentrations (10, 50, 100, 200, or 400µg) of SIF and sacrificed on days 3,7,14,21,30,45,60, and 90. After sacrifice, results in terms of change in body weight, tissue somatic indices, seminal parameters, histology, hematological parameters, lipid peroxidation, testosterone level, and cytokines level were evaluated. The weight profile and TSI of all experimental groups showed no significant change. In case of seminal parameters, 400μg of SIF led to azoospermia up to 90 days and tissue histology also revealed hypo-spermatogenesis. No significant change was observed in haematological parameters after SIF (400µg) administration however, a significant decrease was observed in testosterone levels. The oxidative status and cytokines profile was also affected after SIF (400µg) inoculation. Thus, when administered via intra testis route, SIF can lead to azoospermia and poses to be a potent and safe antifertility agent.

Carbon nanomaterial properties help to enhance xylanase production from recombinant Kluyveromyces lactis through a cell immobilization method.

Carbon nanomaterials, due to their catalytic activity and high surface area, have potential as cell immobilization supports to increase the production of xylanase. Recombinant Kluyveromyces lactis used for xylanase production was integrated into a polymeric gel network with carbon nanomaterials. Carbon nanomaterials were pretreated before cell immobilization with hydrochloric acid (HCl) treatment and glutaraldehyde (GA) crosslinking, which contributes to cell immobilization performance. Carbon nanotubes (CNTs) and graphene oxide (GO) were further screened using a Plackett-Burman experimental design. Cell loading and agar concentration were the most important factors in xylanase production with low cell leakage. Under optimized conditions, xylanase production was increased by more than 400% compared to free cells. Immobilized cell material containing such high cell densities may exhibit new and unexplored beneficial properties because the cells comprise a large fraction of the component. The use of carbon nanomaterials as a cell immobilization support along with the entrapment method successfully enhances the production of xylanase, providing a new route to improved bioprocessing, particularly for the production of enzymes. KEY POINTS: • Carbon nanomaterials (CNTs, GO) have potential as cell immobilization supports. • Entrapment in a polymeric gel network provides space for xylanase production. • Plackett-Burman design screen for the most important factor for cell immobilization.

Public Input Provision, Tax Base Mobility, and External Ownership

This article investigates the distortionary impacts of tax base mobility and external ownership on public input provision. Regional governments compete for mobile tax bases (e.g., business capital). The impact of regional public policy partially accrues to non-residents because immobile factors (e.g., business land) are subject to external ownership. This article derives an optimal rule for regional public input provision that illustrates how these two distortionary impacts depend on the nature of production functions. The impact of external ownership is particularly complex. To explore this impact in detail, the case of production functions with constant elasticity of substitution is examined. Public inputs with different productivity impacts yield fairly different implications of external ownership for inefficient public input provision.

Phosphorus and metals immobilization by periphyton in a shallow eutrophic reservoir

Abstract: Aim: This study evaluated and compared the changes in the Total Phosphorus (TP) and metals (Cd, Cu, Ni and Pb) contents and accumulation rates in the periphyton on different substrate types (PET and glass) in wet and dry periods in a shallow eutrophic reservoir. Thus, the potential of periphyton as a green biotechnology to remediate the eutrophication and promoting metal uptake were investigated. Methods: Floating substrate carriers made of wood (n = 3) containing glass and PET slides were submerged close to a sewage inflow site. Substrate exposure time was about 33 days in each period. Results: Periphyton TP and metal contents (Cu, Ni and Pb) were influenced by seasonality and the highest contents were found in the wet period. Periphyton metal contents were significantly different between glass or PET substrates, but no differences were detected in the TP contents. Conclusions: Seasonality was a determining factor for immobilization of TP and metals in periphyton. The highest potential of TP and metals immobilization by periphyton were detected in the wet period. Our results provided insights that the periphyton can contribute to remediate eutrophication and metal removal in aquatic ecosystems.

Treatment of Pneumococcal Infection by Using Engineered Human C-Reactive Protein in a Mouse Model.

C-reactive protein (CRP) binds to several species of bacterial pathogens including Streptococcus pneumoniae. Experiments in mice have revealed that one of the functions of CRP is to protect against pneumococcal infection by binding to pneumococci and activating the complement system. For protection, however, CRP must be injected into mice within a few hours of administering pneumococci, that is, CRP is protective against early-stage infection but not against late-stage infection. It is assumed that CRP cannot protect if pneumococci got time to recruit complement inhibitor factor H on their surface to become complement attack-resistant. Since the conformation of CRP is altered under inflammatory conditions and altered CRP binds to immobilized factor H also, we hypothesized that in order to protect against late-stage infection, CRP needed to change its structure and that was not happening in mice. Accordingly, we engineered CRP molecules (E-CRP) which bind to factor H on pneumococci but do not bind to factor H on any host cell in the blood. We found that E-CRP, in cooperation with wild-type CRP, was protective regardless of the timing of administering E-CRP into mice. We conclude that CRP acts via two different conformations to execute its anti-pneumococcal function and a model for the mechanism of action of CRP is proposed. These results suggest that pre-modified CRP, such as E-CRP, is therapeutically beneficial to decrease bacteremia in pneumococcal infection. Our findings may also have implications for infections with antibiotic-resistant pneumococcal strains and for infections with other bacterial species that use host proteins to evade complement-mediated killing.

Sperm impairing microbial factor: potential candidate for male contraception

BackgroundDespite significant advances in contraceptive options for women, vasectomy and condoms are the only options available for male contraception. Due to this limitation, the burden of contraception resides on the shoulders of females only. Therefore, there is an urgent need to develop a safe, effective and reversible method of contraception for men. Amongst the alternative approaches, microbial derived products are gaining attention of the scientific world to combat unintended pregnancies. Earlier in our laboratory, sperm impairing microbial factor (Sperm immobilization factor) isolated from Staphylococcus aureus has shown excellent contraceptive efficacy in female mice. Keeping this in mind, the present study was carried out to exploit the sperm immobilization factor (SIF) as potential male contraceptive using vas deferens for administration in mouse model.MethodsSIF (10, 50, 100 or 200 μg) was inoculated in the lumen of right vas deferens whereas the left vas deferens served as control. The mice were sacrificed at Day 3, 7, 14, 21, 30, 45, 60 and 90 after inoculation and the results in terms of change in body weight, seminal parameters, Tissue somatic indices (TSI), haematological parameters, serum level of testosterone, lipid peroxidation and histology were studied. In order to ratify the SIF induced azoospermia SIF (200 μg) was administered with different doses viz. 100, 200, 300, 400 or 500 μg of SIF binding receptor extracted from mouse spermatozoa.ResultsThe weight profile studies of all the experimental groups showed no significant change in the initial and final body weight. In case of seminal parameters, the results revealed that right vas deferens treated with SIF showed azoospermia and with 200 μg of SIF it persisted up to 90 days. TSI of reproductive organs and non-reproductive organs showed no significant change in all the experimental groups. The haematological indices were found to be unaltered throughout the course of investigation however significant decrease in testosterone level was observed in the treated mice. The treatment also affected the oxidative status of the testis. Further, histological studies revealed hypospermatogenesis and late maturation arrest on treated side whereas the left side which served as control showed normal tissue histology. SIF induced azoospermia was ameliorated when administered with 400 μg of SIF binding receptor from mouse spermatozoa.ConclusionSIF, when administered via intra vas deferens route, could lead to complete azoospermia. Therefore, it could be considered as a potential male contraceptive.

Mechanisms affecting the delayed efficiency of cement based stabilization/solidification processes

The paper investigates the efficiency of a cement-based stabilization/solidification treatment conducted on a chromium-contaminated soil. The aim of the paper is to understand the main mechanisms responsible for metal immobilization, and to verify if delayed reactions, due to the presence of additives, may decrease the overall efficiency of the process. The study is conducted testing, as additives, either natural pozzolan and/or fly ashes. Used materials are chemically characterized, and analyzed through X-ray diffraction, thermogravimetric and differential scanning calorimetry analysis, and sequential extraction. Metal leaching experiments and water absorption tests are conducted on stabilized/solidified samples. Results obtained on cured specimens and six months after curing time are compared to verify the effect of delayed reactions. Obtained results indicate that the development of hydration reaction associated to alkaline conditions increases up to 10% the residual fraction of the metal, reducing its mobility (stabilization). The effect of solidification, due to metal incorporation in cement hydration products, gives an important contribution to the overall effectiveness of the process. The immobilization factor varies between 6 and 9%, and are therefore several folds higher than the expected values, estimated around 1%. The effectiveness decreases after curing, both in absence of additives, and in presence of fly ashes. In the first case, chromium release goes from 80 to 160 μg L−1. In the second case it increases from less than 30 to more than 150 μg L−1. X-Ray diffraction analysis and water adsorption tests suggest that the loss of efficiency is due to the delayed formation of ettringite, associated to the internal micro cracking of aged specimens, because metal release is mainly regulated by diffusion mechanisms.

Sperm immobilization factor of Candida albicans: A proposed mechanism of infertility in female mice

Candida species are the most frequently isolated fungi, responsible for blood stream and urinary tract infections. Various studies have shown Candida albicans to be associated with impediment of sperm parameters. Therefore to determine the underlying mechanism, the standard strain of Candida albicans (MTCC 1637) was employed and it was found to cause complete immobilization of mouse spermatozoa in vitro. Further, sperm immobilization activity was shown by only cell-free supernatant, indicating that the sperm immobilization factor might be released extracellularly, as no activity was observed with the washed cells. The sperm immobilization factor (SIF) from supernatant was precipitated out with ammonium sulphate at the saturation of 60% to 80% and was purified by gel permeation chromatography followed by ion exchange chromatography.

Temporal Changes in the Efficiency of Biochar- and Compost-Based Amendments on Copper Immobilization in Vineyard Soils

Copper (Cu)-based fungicides have been an important tool against disease in viticulture since the 19th century. However, their prolonged use can lead to Cu accumulation in the soil and negatively affect soil microbiology and plant growth. The application of biochar (BC)-based amendments is a promising mitigation strategy, due to BC’s longevity in the soil and its potential to complex Cu. This study investigated temporal changes in the efficiency of various compost- and BC-based amendments to immobilize Cu in a calcareous and a slightly acidic Austrian vineyard soil. The immobilization of both historically accumulated Cu and freshly spiked Cu (250 mg kg−1) was studied. The soils were treated with six combinations of amendments containing compost and BC, with and without surface modification, as well as an additional lime treatment for the acidic soil. After treatment, the soils were incubated for 6 weeks and 3 years, after which the 0.01 M CaCl2-extractable Cu was measured. The amendments were not effective in reducing the mobility of the historically accumulated Cu in the calcareous soil, with pure compost doubling the soluble Cu. Pure wood-chip BC was the only organic amendment that led to a reduction (by 20%) of soluble Cu after 6 weeks in the acidic soil; however, after 3 years, the same amendment reduced soluble Cu by 40% and all other tested amendments were also effective in reducing the mobility of the historically accumulated Cu. The lime treatment achieved the greatest reduction in Cu mobility (56%). Freshly spiked Cu was strongly immobilized in both unamended soils, with 0.06% and 0.39% extractable after 6 weeks in the calcareous and slightly acidic soil, respectively. The amendments did not effectuate additional Cu immobilization in the calcareous soil, but in the acidic soil, the soluble Cu was further reduced to between 25% and 50% of the unamended control by the tested organic amendments and to 6% by the lime treatment after 6 weeks of incubation. Overall, the acidic soil exhibited a stronger response to the amendments than did the calcareous soil, suggesting the amendments’ effect on the soil pH was an important factor for Cu immobilization in this study. These results show the importance of developing site-specific remediation strategies for Cu accumulation in agricultural soils.

Production inefficiency, cross-ownership and regional tax-range coordination

Using a simple asymmetric capital-tax competition model where the allocation of mobile capital is distorted in non-cooperative equilibrium, this paper analyzes the welfare impact of regional tax coordination on a range of possible tax rates (a combination of maximum and minimum capital taxes made by a subset of regions). Under the assumption that the ownership of immobile factors (e.g., business land) is diversified across regions, a new possibility of beneficial coordination arises which has not been identified before: tax-range coordination “among capital-exporting regions” or “among capital-importing regions” may improve the welfare of all regions. This is in contrast to the case without cross-ownership where both capital-exporting and capital-importing regions must be involved in tax-range coordination in order to achieve a Pareto improvement.

Shared Antigenic Determinants Between Spermatozoa and Bacteria: An Experimental Study

Sperm immobilization factor (SIF), the secretory protein of Staphylococcus aureus, is known to cause complete immobilization, death and morphological alterations in mouse spermatozoa in vitro. However, the present study aims to explore a newer dimension of SIF i.e., to bind to motile and non-motile bacteria and its ability to induce immobilization of motile bacteria in vitro. The results showed that 800µg of SIF caused complete immobilization of motile bacteria, however, death and morphological alterations could not be observed even with 1000µg of SIF. Furthermore, this SIF-mediated bacterial immobilization was reversed when each of the SIF-binding receptor from mouse spermatozoa and bacteria (Escherichia coli and Streptococcus pyogenes) was incubated with bacteria, thereby, providing an experimental evidence of similarity between the antigenic determinants present on spermatozoa and bacteria against a common ligand, SIF.