Enhancement of TbIII-CuII single-molecule magnet performance through structural modification

We report a series of 3d–4f complexes {Ln2Cu3(H3L)2Xn} (X=OAc−, Ln=Gd, Tb or X=NO3−, Ln=Gd, Tb, Dy, Ho, Er) using the 2,2′-(propane-1,3-diyldiimino)bis[2-(hydroxylmethyl)propane-1,3-diol] (H6L) pro-ligand. All complexes, except that in which Ln=Gd, show slow magnetic relaxation in zero applied dc field. A remarkable improvement of the energy barrier to reorientation of the magnetisation in the {Tb2Cu3(H3L)2Xn} complexes is seen by changing the auxiliary ligands (X=OAc− for NO3−). This leads to the largest reported relaxation barrier in zero applied dc field for a Tb/Cu-based single-molecule magnet. Ab initio CASSCF calculations performed on mononuclear TbIII models are employed to understand the increase in energy barrier and the calculations suggest that the difference stems from a change in the TbIII coordination environment (C4v versus Cs)

Sociobiological Control of Plasmid copy number

Background:
All known mechanisms and genes responsible for the regulation of plasmid replication lie with the plasmid rather than the chromosome. It is possible therefore that there can be copy-up mutants. Copy-up mutants will have within host selective advantage. This would eventually result into instability of bacteria-plasmid association. In spite of this possibility low copy number plasmids appear to exist stably in host populations. We examined this paradox using a computer simulation model.

Model:
Our multilevel selection model assumes a wild type with tightly regulated replication to ensure low copy number. A mutant with slightly relaxed replication regulation can act as a “cheater” or “selfish” plasmid and can enjoy a greater within-host-fitness. However the host of a cheater plasmid has to pay a greater cost. As a result, in host level competition, host cell with low copy number plasmid has a greater fitness. Furthermore, another mutant that has lost the genes required for conjugation was introduced in the model. The non-conjugal mutant was assumed to undergo conjugal transfer in the presence of another conjugal plasmid in the host cell.

Results:
The simulatons showed that if the cost of carrying a plasmid was low, the copy-up mutant could drive the wild type to extinction or very low frequencies. Consequently, another mutant with a higher copy number could invade the first invader. This process could result into an increasing copy number. However above a certain copy number within-host selection was overcompensated by host level selection leading to a rock-paper-scissor (RPS) like situation. The RPS situation allowed the coexistence of high and low copy number plasmids. The non-conjugal “hypercheaters” could further arrest the copy numbers to a substantially lower level.

Conclusions:
These sociobiological interactions might explain the stability of copy numbers better than molecular mechanisms of replication regulation alone

Electrochemistry at nanoscale electrodes : individual single-walled carbon nanotubes (SWNTs) and SWNT-templated metal nanowires

Individual nanowires (NWs) and native single-walled carbon nanotubes (SWNTs) can be readily used as well-defined nanoscale electrodes (NSEs) for voltammetric analysis. Here, the simple photolithography-free fabrication of submillimeter long Au, Pt, and Pd NWs, with sub-100 nm heights, by templated electrodeposition onto ultralong flow-aligned SWNTs is demonstrated. Both individual Au NWs and SWNTs are employed as NSEs for electron-transfer (ET) kinetic quantification, using cyclic voltammetry (CV), in conjunction with a microcapillary-based electrochemical method. A small capillary with internal diameter in the range 30–70 μm, filled with solution containing a redox-active mediator (FcTMA+ ((trimethylammonium)methylferrocene), Fe(CN)64–, or hydrazine) is positioned above the NSE, so that the solution meniscus completes an electrochemical cell. A 3D finite-element model, faithfully reproducing the experimental geometry, is used to both analyze the experimental CVs and derive the rate of heterogeneous ET, using Butler–Volmer kinetics. For a 70 nm height Au NW, intrinsic rate constants, k0, up to ca. 1 cm s–1 can be resolved. Using the same experimental configuration the electrochemistry of individual SWNTs can also be accessed. For FcTMA+/2+ electrolysis the simulated ET kinetic parameters yield very fast ET kinetics (k0 > 2 ± 1 cm s–1). Some deviation between the experimental voltammetry and the idealized model is noted, suggesting that double-layer effects may influence ET at the nanoscale

A comparison between the efficacy of methylphenidate and cocaine for nasal vasoconstriction before nasal surgery—A randomized prospective study

Objectives: Cocaine is regularly utilized topically to give the vasoconstriction to nasal medical procedure; However, it is said to create intraoperative cardiovascular unfriendly impacts. Methylphenidate was considered in the place of cocaine as a substitute to look at the vasoconstriction in nasal medical procedure. Methods: Outcome of the study will be examining the vasoconstriction based on a 5-point scale (1 = unacceptable, 5 = excellent), followed by the administration of either 20–30 mg per day methylphenidate or 4% cocaine randomly to the adult patients subjected to nasal septoplasty. Results: Methylphenidate and cocaine were administered with 38 and 28 patients respectively. The quality of vasoconstriction was noticed to be good in both the groups with the median rating of 4.0 and a P value of 0.85. With both the gatherings, the median blood loss was 46 and 58 ml with a p estimation of 0.48. A non-mediocrity delta of 1 point with a p estimation of 0.009 and non-inadequacy delta of 24 ml with a p esteem 0.026 concerning vasoconstriction and blood loss individually is seen which demonstrates methylphenidate is comparable to cocaine. Non importance is noted with the recurrence of ventricular ectopy, ST section changes after nasal packing with the gatherings. Conclusions: With the results obtained, methylphenidate can be very well replaced for cocaine for vasoconstriction in septoplasty. As there are lot many underlying chances for cocaine abuse and administrative issues related to its handling, methylphenidate may serve as a substitute

Combinatorial inhibition of Angiotensin converting enzyme, Neutral endopeptidase and Aminopeptidase N by N-methylated peptides alleviates blood pressure and fibrosis in rat model of dexamethasone-induced hypertension

Angiotensin converting enzyme (ACE), neutral endopeptidase (NEP) and aminopeptidase N (APN) are responsible for generation of vasoactive peptides that regulates vasoconstriction, vasodilation and natriuresis, which altogether regulate blood pressure. Cumulative inhibition of ACE, NEP and APN effectively blocks the progression of respective pathways. In this study, N-methylated peptide inhibitors F-N(Me)H-L, V-N(Me)F-R and R-N(Me)V-Y were synthesized against ACE, NEP and APN respectively, using their respective physiological substrates. F-N(Me)H-L inhibited ACE activity with an IC50 of 83 nmol/L, V-N(Me)F-R inhibited NEP activity with an IC50 of 1.173 mu mol/L and R-N(Me)V-Y inhibited APN activity with an IC50 of 3.94 nmol/L respectively. Further, the anti-hypertensive effect of N-methylated peptides was evaluated using rat model of dexamethasone-induced hypertension. Individual peptides and their cocktail treatment were started from day 6 of the study period and blood pressure was measured on every alternate day during 15 day study. Administration of F-N(Me) H-L (138 +/- 3 mmHg) and cocktail of all the three peptides at a dose of 100 mg/kg significantly reduced systolic blood pressure (SBP) compared to dexamethasone group (SBP of Groups-dexamethasone; (167 +/- 5 mmHg), F-N (Me)H-L (138 +/- 3 mmHg), and Cocktail (122 +/- 3 mmHg). Anti-hypertensive, anti-hypertrophic and anti-fibrotic effects of N-methylated peptides and cocktail was further reflected by the decreased levels of circulating Ang II and increased ANP levels in sera of hypertensive rats along with decrease in collagen deposition in heart and kidney. Though, ACE inhibition is adequate to reduce SBP, targeting NEP and APN along with ACE is beneficial in tackling hypertension and associated fibrosis of heart

International Veterinary Epilepsy Task Force recommendations for a veterinary epilepsy-specific MRI protocol

Epilepsy is one of the most common chronic neurological diseases in veterinary practice. Magnetic resonance imaging (MRI) is regarded as an important diagnostic test to reach the diagnosis of idiopathic epilepsy. However, given that the diagnosis requires the exclusion of other differentials for seizures, the parameters for MRI examination should allow the detection of subtle lesions which may not be obvious with existing techniques. In addition, there are several differentials for idiopathic epilepsy in humans, for example some focal cortical dysplasias, which may only apparent with special sequences, imaging planes and/or particular techniques used in performing the MRI scan. As a result, there is a need to standardize MRI examination in veterinary patients with techniques that reliably diagnose subtle lesions, identify post-seizure changes, and which will allow for future identification of underlying causes of seizures not yet apparent in the veterinary literature. There is a need for a standardized veterinary epilepsy-specific MRI protocol which will facilitate more detailed examination of areas susceptible to generating and perpetuating seizures, is cost efficient, simple to perform and can be adapted for both low and high field scanners. Standardisation of imaging will improve clinical communication and uniformity of case definition between research studies. A 6–7 sequence epilepsy-specific MRI protocol for veterinary patients is proposed and further advanced MR and functional imaging is reviewed

Green Entrepreneurs Challenges and Innovation: The Struggles They Face

Purpose:  A green entrepreneur's enterprise prioritises environmental protection by minimising the negative impact of existing products, services, or processes. It contributes to the beneficial transformation of society. This study discusses green entrepreneur challenges and innovations in Tamil Nadu's Salem District.  The intention of this study is to determine what factors determine the obstacles they experience in their business and how to transform those obstacles into opportunities   Design/methodology/approach:  Snowball sampling is employed to choose the population for this study from Salem's vast population, and the total number of respondents chosen is 50.   Findings: Simple Percentage Analysis, Chi-Square, and the Henry Garrett Ranking Method are utilised for measuring the factors. The result of testing the hypothesis indicates that there is no correlation between age and the influence to start a business using technical or professional knowledge and skill   Future Implications: Our work presents a range of theoretical and practical implications, as previously said, but it is not without limitations. In order to ascertain the direct and indirect effects of stakeholder demands, green dynamic capacity, green innovation, and firm performance, we first propose that future research make use of our framework and conduct a comparison study of small and large enterprise

A Study on Occupational Stress among Arts and Science College Faculties in Kanyakumari District, Tamil Nadu

Purpose:The goal of this research is to explore the occupational stress level of faculties working in Arts and Science College in Kanyakumari District, Tamil Nadu, India. Teachers of any country are respectable and they are valuables to their country. Tomorrow’s nation is in the hands of the teachers who sculpt the students. Among all the profession in the world, there is a significant place for teaching profession. Recent days, teacher’s job is also like a managerial job as they play a multi-dimensional work commitment. In that case, the stress of the teacher’s can’t be avoided, but it can be nullified when they know how to control it.   Theoretical framework:The theoretical framework highlights the directions in carrying out the research. It shows the factors of occupational stress are independent variables and the facilities of Arts and Science colleges are dependent variables. The relationships between the variables are studied in this research.   Design/Methodology/Approach:The primary sources of the data are collected through personal interview and structured questionnaire and the statistical analysis is carried out through Percentage analysis, T-test and correlation.   Findings:From the study it is found that occupational stress of female faculties is high when compared with male teachers. The study shows the significant difference was observed among male and female faculties on occupational stress. The factors that cause occupational stress is also discussed in the study. A significant and positive correction is observed among the varieties of occupational stress.   Research, practical &  social  implications: The college management should look for some aid from psychologists to direct faculties freeing from their frustration and anger. College management can provide training and workshops which helps to enhance the skills of faculties and develop a rapport among co-workers.    Originality/value:The variables of the studies are analysed and it shows the meaningful effect on the occupational stress of faculties. Then the research is concluded with the certainty that occupational stress of the facilities is nullified and the performance will be increased

Design of an Intelligent Controller for Armature Controlled DC Motor using Fuzzy Logic Technique

This paper presents a fuzzy control approach to the speed control of DC shunt motor using armature control. This paper presents concept of development of conventional controller and the design of a fuzzy logic controller applicable to DC Motor Speed Control System (MSCS) with high performance of the FL controller. Since armature voltage supply has a major influence in controlling speed, therefore one of the inputs to the proposed FL Controller will be actual armature voltage supply (Va) while another input will be error (e) in speed. The transfer function model of the DC shunt motor has been obtained via experimentation and calculations and simulated and then as per requirement and specification, the proposed fuzzy logic controller has been designed and simulated using Fuzzy Logic and Simulink Toolboxes of MATLAB 7. Results show robustness against changing loading conditions