Oligorotaxane radicals under orders

A strategy for creating foldameric oligorotaxanes composed of only positively charged components is reported. Threadlike components-namely oligoviologens-in which different numbers of 4,4'-bipyridinium (BIPY(2+)) subunits are linked by p-xylylene bridges, are shown to be capable of being threaded by cyclobis(paraquat-p-phenylene) (CBPQT(4+)) rings following the introduction of radical-pairing interactions under reducing conditions. UV/vis/NIR spectroscopic and electrochemical investigations suggest that the reduced oligopseudorotaxanes fold into highly ordered secondary structures as a result of the formation of BIPY(\u2022+) radical cation pairs. Furthermore, by installing bulky stoppers at each end of the oligopseudorotaxanes by means of Cu-free alkyne-azide cycloadditions, their analogous oligorotaxanes, which retain the same stoichiometries as their progenitors, can be prepared. Solution-state studies of the oligorotaxanes indicate that their mechanically interlocked structures lead to the enforced interactions between the dumbbell and ring components, allowing them to fold (contract) in their reduced states and unfold (expand) in their fully oxidized states as a result of Coulombic repulsions. This electrochemically controlled reversible folding and unfolding process, during which the oligorotaxanes experience length contractions and expansions, is reminiscent of the mechanisms of actuation associated with muscle fibers

Pyrrole studies part 47. C NMR Spectroscopic characterisation of the products of the reaction of formylpyrroles with aniline and diaminobenzenes

Pyrrole-3, 4-dicarboxaldehydes react with aniline to produce" bis-imines" having a 3H-pyrrole structure, 3b. In contrast, pyrrole-2-carboxaldehyde and pyrrole-2, 5-dicarboxaldehydes produce 1H-pyrrolylmethylenimines. Benzimidazolyl derivatives, are formed exclusively from the reaction of β-formylpyrroles with 1, 2-diaminobenzene, while α-formylpyrroles form 2: 1 bisimines or benzimidazoles depending upon the reaction conditions. Pyrrole-2, 4-dicarboxaldehydes react with aniline preferentially at the 4-CHO group. With an excess of aniline, the bis-imine is produced

Letrozole: A Steroid-Free Estrous Synchronization Method

Most bovine estrous synchronization protocols utilize progesterone plus estrogen to control ovulation timing. A drug that inhibits estrogen production (Letrozole) may be an alternative, steroid-free synchronization method (not yet commercially available). However, low estrogen can negatively affect the health of follicles/oocytes and impact fertility. To determine its effects, Letrozole was administered intramuscularly while tracking follicle growth and circulating hormones. Letrozole response was variable. Two of three cows experienced delayed luteolysis/ovulation and extended progesterone production. This preliminary data indicates that Letrozole treatment allows normal follicle progression but drug response may vary and little is known about effects on oocyte quality

Pancreatic cancer: Incidence, clinical profile, and frequency of associated factors in Kuwait

Background: Pancreatic cancer is an uncommon tumor, but because the mortality rate approaches 100%, this form of cancer has now become a common cause of cancer mortality. Diabetes has been postulated to be both a risk factor and a consequence of pancreatic cancer, but the degree of risk and associated clinical factors remain unclear.Objectives: The objectives of this study were to investigate the incidence, clinical profile, and the frequency of associated factors of pancreatic cancer in Kuwait.Methods: The study design was a retrospective hospital-based record study in which records of 251 pancreatic cancer patients registered, evaluated and treated at Kuwait cancer control center from January 2004 through December 2010 were studied.Results: The overall pancreatic cancer incidence was 0.9/100000 population. Pancreatic cancer was more frequent in older, obese, smoker, diabetic Kuwaiti males with family history of pancreatic cancer. Metastasis was diagnosed in 67.7% of patients at diagnosis of pancreatic cancer.Conclusions: Pancreatic cancer in Kuwait is diagnosed in late stages. Screening for this disease was indicated specially in diabetic patients. A comprehensive comparative study is required for determination of risk factors that could be associated with the disease.Keywords: Pancreatic cancer; Profile; Diabetes mellitu

Therapeutic efficacy of intravenously administered transferrin-conjugated dendriplexes on prostate carcinomas

Aim: Improved treatments for prostate cancer are critically needed in order to overcome metastasis and lethal recurrence. Intravenously administered gene therapy would be an attractive anticancer treatment strategy; however, the lack of suitable carrier systems able to selectively deliver therapeutic genes to tumors has so far limited this investigation. Given that transferrin receptors are overexpressed on prostate cancer cells, the purpose of this study is to determine whether transferrin-conjugated dendriplexes encoding TNF-α, TNF-related apoptosis-inducing ligand and IL-12 would suppress the growth of prostate cancer cell lines in vitro and in vivo. Materials & methods: Transferrin-conjugated dendriplexes encoding TNF-α, TNF-related apoptosis-inducing ligand and IL-12 were intravenously administered to mice bearing subcutaneous PC-3 and DU145 tumors. Results: The administration of the transferrin-conjugated generation 3 diaminobutyric polypropylenimine dendriplex encoding TNF-α resulted in tumor suppression for 60% of PC-3 and 50% of DU145 prostate tumors. Conclusion: These dendriplexes hold great potential as a novel approach for prostate cancer therapy

Physical fitness and physical self-concept of male and female young adults in Qatar

Background Physical inactivity is high within the Qatari population, particularly within females, and school-based environments, contributing to increased morbidity and mortality. School-based physical activity (PA) outcomes may be mediated by physical self-concept. Low physical self-concept may negatively impact PA engagement, compromising childhood and adolescent physical fitness, which may translate into adulthood. Normative physical fitness data for the Qatari population is unavailable. Stratifying normative physical fitness appears prudent, to not only allow comparisons to be made worldwide, but enable informed decisions for public health policy and future interventions in the Qatari population.Scopu

Nonlinear Optical Properties of Polythiophene and Iodine Doped Thin Films by Aerosol Assisted Plasma Jet Polymerization at Atmospheric Pressure

In this work, the nonlinear optical properties of pure Polythiophene and in situ iodine doping Polythiophene thin films on glass substrate, prepared by aerosol assisted plasma jet polymerization at atmospheric pressure, thin films were studied through open and closed Z-scan technique under laser excitation at 532 nm, CW solid state laser with an output power of 100 mW. The nonlinear optical properties of pure Polythiophene thin films prepped at different gas flow rate and Polythiophene thin films iodine doped at constant gas flow rate 1lm-1 and different iodine weight concentration 1, 3, 5, and 7%were studied. the closed aperture Z-scan data indicates that the sign of the refraction nonlinearity is negative for thin films prepared at gas flow rate 1lm-1, 2lm-1 n2 0.938×10-5 and 1.247×10-5 cm2/mw .and positive nonlinearity for thin films prepared at other gas flow rate, n2 1.409×10-5 and 1.547×10-5 cm2/mw for gas flow rate 3 and 4 lm-1 respectively. And the open Z-scan measurements show two photon absorption β cm/mW, 2.797cm/mW for gas flow rate 4lm-1 show saturated absorption β cm/mW, 0.993, 1.25 and 0.3 cm/mW for all gas flow rate1, 2 and 3 lm-1 respectively. For Polythiophene thin films iodine doped at constant gas flow rate the closed aperture Z-scan measurements shows positive nonlinearity for thin films prepared at iodine concentration 1,3 and 7% n2 2.510×10-5, 2.101×10-5and  1.638×10-5 cm2/mw respectively.While thin films prepared with iodine concentration 5% shows negative nonlinearity n2 2.343×10-5 cm2/mW respectively. The open aperture Z-scan measurements for Polythiophene thin films doped with iodine by different concentration 1, 3, 5, and 7% and constant gas flow rate show saturated absorption β cm/mW, 2.140 and 2.001 cm/mW at iodine concentration 5 and 7% for all for all gas flow rate show two photon absorption β cm/mW, 1.763 and 2.037 cm/mW. It can be concluding that, the possibility of obtaining direct and inexpensive method to prepare saturated absorption thin films material, by aerosol assisted plasma jet polymerization at atmospheric pressure.

Spectrum investigation for sharing analysis between BWA system and FSS receiver

In this research, testing the compatibility between Fixed Broadband Wireless Access (BWA) as a case study for the International Mobile Telecommunication (IMT-Advanced) and Fixed Satellite Services (FSS) networks in 3400-4200MHz range (C-band) has been studied and discussed in details. The interference between Fixed Satellite Service earth station(FSS ES) and Broadband Wireless Access(BWA) is considered and the aim of the article is to avoid interference between FSS ES and BWA by using minimum separation distance. Possibility of coexistence and sharing analysis were obtained by taking into account the detailed calculations of the most useful formulas for path loss effect and clutter loss by using the existing parameters of FSS and the BWA base station parameters located in the wireless communication center, Universiti Teknologi Malaysia (UTM). In-band interference has been concluded, analyzed and simulated (using Matlab) for several environments (rural, suburban, urban and densurban) in response to different clutter altitude. Channel prediction for two scenarios (rural and suburban) as a trail map was delineated by ATDI software. Simulation results indicate that the proposed mitigation scheme is highly efficient in terms of reducing the separation distances. Comparing the measurements with simulated result has also been done with high percentage of accuracy to show the amount of closeness or similarity between both results

Attainment and maintenance of pubertal cyclicity may predict reproductive longevity in beef heifers

We hypothesized the manner that heifers achieve puberty may indicate their future reproductive longevity. Heifers with discontinued or delayed cyclicity during puberty attainment may have irregular reproductive cycles, anovulation, and infertility in their first breeding season contributing to a shorter reproductive lifespan. Therefore, plasma progesterone (P4) was measured from weaning to breeding on 611 heifers born 2012–2017 and four pubertal classifications were identified: (1) Early; P4 ≥ 1 ng/ml \u3c March 12 with continued cyclicity, (2) Typical; P4 ≥ 1 ng/ml ≥ March 12 with continued cyclicity, (3) Start-Stop; P4 ≥ 1 ng/ml but discontinued cyclicity, and (4) Non-Cycling; no P4 ≥ 1 ng/ml. Historical herd records indicated that 25% of heifers achieved puberty prior to March 12th in the 10 years prior to the study. Start-Stop and Non-Cycling yearling heifers were lighter indicating reduced growth and reproductive maturity traits compared with Early/Typical heifers. In addition, Non-Cycling/Start-Stop heifers were less responsive to prostaglandin F2 alpha (PGF2α) to initiate estrous behavior and ovulation to be artificially inseminated. Non-Cycling heifers had fewer reproductive tract score-5 and reduced numbers of calves born in the first 21-days-ofcalving during their first breeding season. Within the Start-Stop classification, 50% of heifers reinitiated cyclicity with growth traits and reproductive parameters that were similar to heifers in the Early/Typical classification while those that remained non-cyclic were more similar to heifers in the Non-Cycling group. Thus, heifers with discontinued cyclicity or no cyclicity during puberty attainment had delayed reproductive maturity resulting in subfertility and potentially a shorter reproductive lifespan