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Farnesol is a C15 isoprenyl alcohol generated from the hydrolysis of farnesyl diphosphate under the action of farnesol synthase in plants. Although this sesquiterpenoid alcohol has been exploited in a wide variety of industrial applications, serious discussions on the possible use of this agent in disease treatment have been scant until now. In this article, we review the current understanding of the physiological properties of farnesol and the potential use of the agent as a candidate for treatment development. In fact, since the turn of the last century, farnesol has been found not only to trigger apoptosis in tumor cells but also to be able to function as a quorum-sensing molecule in Candida albicans to influence infection dynamics. By offering a snapshot of recent advances in research on farnesol, it is expected that this article can provide more insights into future research on farnesol for the development of different treatment strategies. [ABSTRACT FROM AUTHOR]

Aim: This retrospective cohort study aimed to evaluate the association between body weight and oral cGVHD (chronic graft versus host disease). Methods: Patients with oral cGVHD were compared with an age and gender-matched non-GVHD cohort in terms of demographic information, body mass index (BMI), date of transplant, length of hospitalization, and oral complications. Weight was stratified in pre-and post-transplant weight, mean weight after acquiring cGVHD for the first year, and post-oral cGVHD BMI. Each patient was matched and compared with two controls at a 1:2 ratio. Firth's penalized likelihood logistic regression was used to investigate the association between oral complications and weight loss greater than 5% in the oral cGVHD group. Results: This study included 137 patients (n = 42 oral cGVHD, n = 12 non oral-cGVHD and n = 83 non-GVHD). The oral cGVHD cohort had a 1.44 times higher risk (RR) of being underweight (BMI<18.5 kg/m2) compared to the non-GVHD cohort. Oral mucositis was an independent predictor of weight loss above 5% in the oral cGVHD cohort (p < 0.001) Conclusion: The weight loss was more prevalent among oral cGVHD, and oral mucositis was linked to significant weight loss. Weight loss may indicate the need to initiate early and aggressive symptomatic oral cGVHD treatment. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship of serum homocysteine, folic acid, and vitamin-B12 levels with recurrent pregnancy loss (RPL). Methods: A case-control study was conducted in the Department of Gynecology and Obstetrics, Dr. Ruth Pfau Civil Hospital, Karachi from July 2021 to June 2022. Total 124 participants were recruited from gynecology outpatient department after taking informed consent. The participants included 62 females with two or more consecutive unexplained RPLs and 62 healthy women having at least two successful deliveries without any pregnancy loss. Serum folic acid and vitamin-B12 levels were measured by chemiluminescent method and serum homocysteine was measured by enzyme-linked immunosorbent assay (ELISA). Comparison of quantitative variables with RPL cases and control was done by Mann-Whitney U-test (for non-normally distributed data) and independent sample t-test (for normally distributed data), while Pearson’s chi-square test was used for the association of qualitative variables with RPL cases and control. Correlation of homocysteine with vitamin-B12 and folic acid was assessed in RPL cases. Results: The median age of the study population was 27 (IQR 25-32) years. The median body mass index (BMI) was 26.25 (IQR 22-29) kg/m2. Cases had significantly lower serum folic acid (p-value=0.022), while vitamin-B12 was decreased in cases as compared to controls (p-value=0.295). Mean concentration of serum homocysteine was higher in RPL cases as compared to controls (p-value=0.094). There was significant association of serum vitamin B12 (p-value=0.001) and folic acid levels (p-value=0.004) with RPL. The homocysteine was not significantly correlated with vitamin-B12 (r=0.124, p=0.338) and folic acid (r=0.067, p=0.606) in the RPL group. Conclusion: Reduced level of serum folic acid and vitamin B12 was significantly associated with RPL cases, while homocysteine was marginally raised however the difference was not significant. Folic acid and vitamin B12 supplementation before next pregnancy in RPL patients is likely to be beneficial in improving pregnancy outcomes. [ABSTRACT FROM AUTHOR]

The aim of the present work is to apply the fractional derivative to the heat transformation of a nanofluid along with ramped wall temperature. The flow is analyzed under the effect of magnetohydrodynamic together with heat transfer. A nanofluid under the application of fractional-order differential equations by Caputo–Fabrizio derivatives with respect to time has the ability to explain the behavior of nanofluid under the influence of memory concept. For the same purpose, Caputo–Fabrizio time-fractional derivative is applied to investigate the behavior of nanoparticles on the thermal conductivity of a fluid. Appropriate nondimensional variables are engaged in the equation which governs the problem and guides us to obtain the exact solutions for the fields of velocity and temperature. These obtained solutions for the nondimensional set of governing equations are found by extracting them from the governing equations by applying Laplace transform techniques along with Caputo–Fabrizio time-fractional derivative. The influence of the fractional variable on the velocity, temperature, and Nusselt number is graphically exposed and discussed. The velocity for the state of wall temperature as ramped falls down with the enlarging values of the fractional parameter. Variation in Nusselt number is shown in the tabular form. Solutions are visualized graphically to make an analysis of how the variation is taking place in the physical behavior of the nanofluid flow with respect to the change in distinct physical parameters. The obtained results here will have useful industrial and engineering implementations. It is found that fluid velocity in the flow direction decreases with the increase in the magnetic parameter. The relationship of fractional parameter with the velocity and temperature of the nanofluid is found as direct proportional for a smaller time. However, this direct proportionality converts into inverse proportionality for larger values of time. It is observed that the increase in the nanoparticles volume fraction causes an increase in temperature distribution. It is due to lower specific heat of nanoparticles and its higher thermal conductivity than that of the base fluid. [ABSTRACT FROM AUTHOR]

From the rare species that cause urinary tract infections, seven different types of coagulation-negative Staphylococcus bacteria were isolated (9.82%) Staphylococcus epidermidis (8.9%) Staphelococcus haemolyticus, (3%) Staphylococcus xylosus (0.89%) for each bacteria Staphylococcus auricularis, Staphylococcus simulans, Staphylococcus hominis, and Staphylococcus lugduensis, as all isolates were 100% producers of biofilms by tube method and (40%) of Congo Red by Staphelococcus. haemolyticus, while the rest of the species were not producers by the Congo Red method and all isolates were fully resistant to the antibiotics. Amoxicillin/Clavulanic Acid, Oxacillin, Cefotaxim, Cefepime, Levofloxacin, and in a high percentage of cases highly sensitivite to the antibiotics Rifampcin and Amikacin. [ABSTRACT FROM AUTHOR]

BACKGROUND & OBJECTIVE: Piperacillin is an antibiotic that belongs to the ureidopenicillin family. Piperacillintazobactam provides cover against gram-positive, gram-negative bacteria and some bacteria of anaerobic nature. It is an extended-spectrum antibiotic and is used along with tazobactam which is an inhibitor of beta-lactamase. The main objective of our research was to identify the hypersensitivity reactions of piperacillin-tazobactam in pharmaceuticals factory and office workers. METHODOLOGY: A Cross-sectional study was conducted at Stallion Pharmaceuticals (Pvt) Ltd located at Sundar Industrial Estate Lahore, Pakistan, from March to April 2018, after approval from the institutional research committee. All the workers, including factory workers and office workers at Stallion Pharmaceuticals (Pvt) Ltd were included in this study. Data was collected from each respondent by immediate-type skin testing. Data analysis was done by SPSS version 25, the demographic data was evaluated by descriptive statistics, Fisher Exact test was used for comparison and p≤0.05 was taken as significant. RESULTS: The results of the study presented that hypersensitivity reaction was present in (7.5%) of males and (3.8%) of females. It was also observed that (8.8%) of factory workers had hypersensitivity reactions when they are gone through skin tests, and only (2.5%) of office workers were skin test positive. From the above results (11.2%) of all the respondents developed hypersensitivity reactions and (88.8%) showed no reaction when they were gone through skin tests, which contain 0.1 ml of piperacillin and tazobactam. Fisher exact test was applied, and results showed no significant difference between hypersensitivity reactions among factory and office workers as the p-value was 01. CONCLUSION: Hypersensitivity reaction to piperacillin-tazobactam was minimal in the factory & office workers, and this was not significant. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor L.) is ranked five cereal crop worldwide. It belongs to the Poaceae family and is formally part of plant-derived food. Nutritionally, it is composed of carbohydrates, kafirin (protein), polyunsaturated fatty acids (PUFA), fibers and resistant starch. Sorghum is used in three different fields: food, feed, and biomass production. Phenolic compounds including phenolic acid, flavonoids, stilbenes and tannins, vitamins including B-complex, A, D, E and K and the minerals (potassium, phosphorus, magnesium and zinc) were involved in the bioactivity of sorghum. The functional composition of sorghum plays an essential role in human health by inhibiting the risk of chronic diseases. Available epidemiological evidence suggests that tannin (proanthocyanidins) in sorghum acts as an antioxidant protecting from inflammation and cancer. Its fiber content can reduce blood cholesterol and glucose level, and is also helpful in celiac disease. Phytochemicals in sorghum enhance cardiovascular health in animals. These properties have not been reported in humans, which needs investigation. This review aims to describe the available information on the bioactive characteristics of sorghum, how it is used in different functional foods, and how it has the potential to combat various disorders. The literature has been collected from Google Scholar, Science Direct, PubMed and Web of Science. [ABSTRACT FROM AUTHOR]

An active attitude control system using a novel six-layer electromagnetic embedded printed magnetorquer for a 3-U nanosatellite is presented in this paper. The proposed design was optimized in terms of size, dissipated power, torque produced, and generated magnetic dipole moment. The designed printed magnetorquer is the optimum choice for a 3-U small-satellite attitude stabilization in terms of reconfigurability, modularity, lower space occupation, low mass, and lower cost. The printed magnetorquer was designed and analyzed for a 3-U nanosatellite with CubeSat standard dimensions of 10×10×30 cm3. The design was implemented with commercial off-the-shelf (COTS) high-performance microdevices that are reliable and easily accessible for reducing procurement cost. The printed magnetorquer was embedded in internal layers of a printed circuit board (PCB) that does not require additional space on the satellite. Time-varying rotational analyses were performed for various coil arrangements to test the rotation times for spin-stabilized 3-U nanosatellites. Thermal analysis of the 3-U nanosatellite was done to sustain thermal operation and satisfy the feasibility requirements of the system. Essential performance parameters like magnetic moment generated, resultant torque, and power dissipation were examined for comparison with the existing commercial state of the art. The proposed printed magnetorquer with more configurability (2×3 , 3×2 , 1×18 , 18×1 , 9×2 , 6×3 hybrid) features provides versatility to the design aspects by changing the configuration through the onboard computer according to mission needs. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is one of the most common neurodegenerative diseases. There is accumulating evidence that link gut microbiota to symptomatology and pathophysiology of PD. The aim of this study was to describe the pattern of gut microbiota and its association with PD and identify the effect of environmental factors on gut microbiota. This case–control study included 46 patients diagnosed as Parkinson's disease (PD) and 31 healthy volunteers age and sex matched. Detailed history including age of onset, duration of disease, environmental risk factors, diet data, treatment, Unified Parkinson's Disease Rating Scale (UPDRS), and gastrointestinal tract (GIT) domain of Non‐Motor Symptoms Scale (NMSS) were assessed. After extraction of bacterial DNA from the fecal samples, bacterial abundance was quantified by qPCR using 16S rRNA group-specific primers. Results: Significant high abundance of Clostridium cluster IV, Akkermansia, Bifidobacterium, and lactic acid bacteria were found in the PD group compared with the control group (P < 0.001, 0.04, 0.02 and < 0.001, respectively), while Firmicutes were significantly less abundant in the PD group (P < 0.001) compared with the control group. The naive PD patients had significant abundance of Bifidobacterium, and lactic acid compared with control group. Interestingly, Akkermansia was more abundant in treated than untreated patients. There were significant associations between pesticide exposure and Bifidobacterium (P = 0.002), while no significant correlations between different gut microbiota and demographic, environment data, different rating scores or dominant type of PD. There was a significant negative correlation between the Bifidobacterium with the duration of illness (P = 0.012). Conclusion: The present study highlighted a significant connection between PD and levels of certain types of gut microbiota, in support of a possible link between gut microbiota and a neurodegenerative cascade of PD. [ABSTRACT FROM AUTHOR]

Background: This research aimed to assess the current care management processes for COVID-19 and determine patient outcomes. Methods: An analytical cross-sectional study was conducted at Saidu group of teaching hospital, a tertiary care hospital with more than a thousand-bed capacity. The target population was all patients admitted to the corona isolation ward and the hospital's critical unit. All the patients admitted through the emergency and inpatient department with Positive PCR, and respiratory symptoms were included in the study. Results: In total, data of 151 patients were collected. Of these, 90 (59.6%) were male and 61 (40.4%) were female with a mean age of 59.17±13.79. The most common presenting symptoms were difficulty in breathing (n=147, 97.4%) and dry cough (n=104, 68.9%), followed by aches and pain (n=71, 47%) and fever (n=60, 39.7%). Most of the patients had an underlying health condition (n=96, 63.6%). The most common underlying conditions were hypertension (n=65, 43%) and diabetes (n=56, 37.1%). The mean time for the hospital stay was 11.68±15.31. About 64% of the patients recovered with the treatment and care protocols (n=97, 64.2%), while the remaining (n=54, 35.8%) died. Conclusion: This study provides an overview of the clinical presentation and treatment protocol for COVID-19. Most of the patients received supportive treatment comprising of antivirals, steroids, and oxygen therapy. However, the mortality rate was low compared to other hospitals across the country. [ABSTRACT FROM AUTHOR]

To assess the efficacy of butorphanol–azaperone–medetomidine (BAM) and butorphanol–midazolam–medetomidine (BMM) protocols for immobilization of wild common palm civets (Paradoxurus musangus) with subsequent antagonization with atipamezole. Prospective, randomized, blinded clinical trial. A total of 40 adult wild common palm civets, 24 female and 16 male, weighing 1.5–3.4 kg. The civets were randomly assigned for anesthesia with butorphanol, azaperone and medetomidine (0.6, 0.6 and 0.2 mg kg–1, respectively; group BAM) or with butorphanol, midazolam and medetomidine (0.3, 0.4 and 0.1 mg kg–1, respectively; group BMM) intramuscularly (IM) in a squeeze cage. When adequately relaxed, the trachea was intubated for oxygen administration. Physiological variables were recorded every 5 minutes after intubation. Following morphometric measurements, sampling, microchipping and parasite treatment, medetomidine was reversed with atipamezole at 1.0 or 0.5 mg kg–1 IM to groups BAM and BMM, respectively. Physiological variables and times to reach the different stages of anesthesia were compared between groups. Onset time of sedation and recumbency was similar in both groups; time to achieve complete relaxation and tracheal intubation was longer in group BAM. Supplementation with isoflurane was required to enable intubation in five civets in group BAM and one civet in group BMM. All civets in group BAM required topical lidocaine to facilitate intubation. End-tidal carbon dioxide partial pressure was lower in group BAM, but heart rate, respiratory rate, rectal temperature, peripheral hemoglobin oxygen saturation and mean arterial blood pressure were not different. All civets in both groups recovered well following administration of atipamezole. Both BAM and BMM combinations were effective for immobilizing wild common palm civets. The BMM combination had the advantage of producing complete relaxation that allowed intubation more rapidly. [ABSTRACT FROM AUTHOR]

Production of hydrogen fuel from water splitting driven by solar energy is an effective technique to overcome the energy crisis and environmental problems in coming decades. To explore low cost and efficient photocatalysts is highly desired. In this work, we study the electronic, optical and photocatalytic properties of MoSSe/BSe (Model-1 and Model-2) vdW heterostructures by PBE and HSE06 functionals using first-principle calculations. The stabilities of these heterostructures are confirmed through phonon spectra and ab initio molecular dynamic simulations. The Model-1 and Model-2 heterostructures have indirect band gaps of 1.95 and 1.54 eV respectively by HSE06 hybrid functional. Interestingly, the transition from indirect to direct band gap occurs in Model-1 after including spin-orbit coupling effect. Remarkably, the high carrier mobilities are quantitatively explored by means of deformation potential theory. Furthermore, the transition from type-I to type-II band alignment happens at compressive strain in both Model-1 and Model-2, which effectively slows down the recombination of electron-hole pairs. Compared to the isolated monolayers, the MoSSe/BSe (Model-1 and Model-2) heterostructures harvest maximum portion of visible spectrum, revealing the outstanding paybacks of high efficiency utilization of solar spectrum. Most intriguingly, the band edges of MoSSe/BSe vdW heterostructures meet the redox potential requirements for water splitting. Our results will be valuable for easing the investigation and applications of MoSSe/BSe heterostructures for optoelectronics and photocatalytic water splitting. [Display omitted] • MoSSe/BSe (Model-1 and Model-2) heterostructures are predicted from first-principles. • Heterostructures are dynamical and thermally stable and with high carrier mobilities. • Heterostructures are promising photocatalysts for water splitting. • Strain induces type-II band alignment for better photocatalytic activity. • The heterostructures harvest maximum portion of visible light. [ABSTRACT FROM AUTHOR]

In this work, a sufficient condition required for the presence of positive solutions to a coupled system of fractional nonlinear differential equations of implicit type is studied. To study sufficient conditions essential for the existence of unique solution degree theory is used. Two examples are given to illustrate the established results. [ABSTRACT FROM AUTHOR]

This paper is devoted by developing sufficient condition required for the existence of solution to a nonlinear fractional order boundary value problem Dγu(ℓ)=ψ(ℓ,u(λℓ)),ℓ∈Z=[0,1],with fractional integral boundary conditions p1u(0)+q1u(1)=1Γ(γ)∫01(1−ρ)γ−1g1(ρ,u(ρ))dρ,and p2u′(0)+q2u′(1)=1Γ(γ)∫01(1−ρ)γ−1g2(ρ,u(ρ))dρ,where γ ∈ (1, 2], 0 < λ < 1, D denotes the Caputo fractional derivative (in short CFD), ψ,g1,g2:Z×R→R are continuous functions and pi,qi(i=1,2) are positive real numbers. Using topological degree theory sufficient results are constructed for the existence of at least one and unique solution to the concerned problem. For the validity of our result, a concrete example is presented in the end. [ABSTRACT FROM AUTHOR]

Objective: The study was performed to investigate the association of hypertension in pregnancy with prostasin gene polymorphism in Pakistani females. Methods: This case-control study was performed at University of Karachi, Pakistan from April 2018 to May 2019. A total of 160 females, including 90 hypertensives and 70 healthy pregnant females, were recruited by purposive sampling after obtaining informed written consent. Genotyping was performed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: The frequencies of the TC and CC genotypes were higher in hypertensive pregnant females compared to healthy controls. A significant difference was evident for CC (P=0.012) genotype; however, no significant difference was observed for TC (P=0.49) and TT genotypes (P=0.06) between control and hypertensive groups. The adjusted odds ratio for CC genotype was 6.2 (P=0.025) and 1.48 (P=0.44) for TC genotype compared to the TT genotype. There was a significantly higher prevalence of the C allele of the prostasin gene at rs12597511 in the hypertensive group, suggesting that this allele is a risk factor for hypertension and cardiovascular diseases. Conclusion: C allele at rs12597511 of prostasin gene demonstrate as a risk factor for having hypertension in pregnancy. [ABSTRACT FROM AUTHOR]

The effects of various vacancies and group‐VIB and VIIB transition metal substitutional doping on the structural, electronic, and magnetic properties of monolayer HfS2 are studied by first‐principles calculations. The results show that pristine monolayer HfS2 is a nonmagnetic semiconductor; it becomes a metal on creating a single V1Hf or V1S vacancy, whereas it is still a semiconductor on creating V1Hf+1S divacancy or V1Hf+2S trivacancy. The V1Hf single vacancy and V1Hf+1S divacancy induce magnetic moments of 3.265 and 2.000 μB, respectively, whereas the V1S single vacancy and V1Hf+2S trivacancy do not induce any magnetic moments. One of the group‐VIB and VIIB transition metal atoms substituting for one Hf atom in the monolayer HfS2 induces magnetic moments of about 2.000 and 3.000 μB, respectively. Furthermore, the spin‐polarized band structures show that the Cr‐doped monolayer HfS2 is a magnetic metal, whereas the Mn‐, Tc‐, and Re‐doped monolayer HfS2 are magnetic semiconductor. The Mo‐ and W‐doped monolayer HfS2 are magnetic half metal with wide spin‐down bandgaps of 0.975 and 1.074 eV, respectively, and thus can be used in nanoelectronics and spintronics devices. [ABSTRACT FROM AUTHOR]

This study attempts to develop an allometric model for biomass estimation of Chirpine (Pinus roxberghii) an important species of subtropical pine ecosystems in the Himalayas. Data was collected through destructive sampling of 32 sample trees growing in subtropical pine forests of Hazara Forest Region, Khyber Pakhtunkhwa (KP), Pakistan. Diameter at Breast Height (DBH) of the selected sample trees ranged from (12-93 cm) and height (H) varied between 9.50-40.10 m. Allometric equation was developed through testing different allometric models. The best fit model was obtained through logarithmic transformation of response and explanatory variables. It was found that square of DBH and H (D²H) was the best independent variable for predicting above ground biomass of an individual tree. The equation was also evaluated and compared with the existing generic allometric equations. Results showed that the allometric equation developed in this study gave more reliable estimates of aboveground biomass. A strong relationship (r² = 0.99) found for tree biomass as response variable and DBH with height as explanatory variables. The significance of the model was demonstrated by F and P values. The model was found a good fit on the basis of values of sum of square (SS) of the residuals and standard error. Homogeneity of variance and normality of residuals were also validated for checking accuracy of the model. The result can be used for estimation of the above ground biomass and carbon stocks in subtropical pine forests of the Khyber Pakhtunkhwa and other areas which represent similar ecological conditions. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is a chronic progressive neurodegenerative disabling disease and involves about 1–3% of the worldwide population over the age of 60. A significant prevalence of psychopathological symptoms has been recorded as most patients with PD developed over their disease course neuropsychiatric symptoms such as depression, anxiety, sleep disorders, psychosis, and cognitive and behavioral abnormalities. These non-motor symptoms, which could appear decades before motor ones, become disturbing symptoms during the later phases of the disease. Hence, the current research aims to study depressive symptoms in Parkinson's disease patients. Thirty-six patients with Parkinson's disease aged from 40 to 65 years (20 males and 16 females) and 36 age and sex-matched controls (19 males and 17 females) were included in the study. Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn and Yahr scale, Schwab and England's scale, Mini-Mental State Examination, Cognitive Ability Screening Instrument, and Hamilton Depression Rating Scale were applied to assess depression in both groups. Results: Patients were 20 males and 16 females (mean age 52.44 ± 7.45), mean duration of Parkinsonism was 3.88 years. The mean value for Hoehn and Yahr scale was 1.97 ± 1.42, for UPDRS T was 42.41 ± 20.91 and Schwab England's scale was 74.77 ± 17.78. Concerning cognition, MMSE was significantly lower among patients 25.33 ± 3.63, than in the control group and CAS total was significantly lower in patients (16 ± 71.35) than in the control group 9.81 ± 84.62. Conclusion: Depressive symptoms are widespread in Parkinson's disease. Depression should be strictly determined and addressed, particularly in patients with more advanced cognitive impairment who are at a higher risk of developing or worsening depression. [ABSTRACT FROM AUTHOR]

Abstract Background Takotsubo syndrome (TS) is an acute cardiac syndrome characterized by regional myocardial akinesia that is not caused by coronary artery occlusion. Exogenous as well as endogenous excess catecholamines can induce TS. The aim of this study was to explore the effects of pharmacological cardio-simulative and cardio-depressing drugs on the development of isoprenaline-induced takotsubo-like cardiac dysfunction, a rat model of TS. Methods We randomized 295 rats into twelve groups. The animals were randomized to pre-treatment with either a low or high dose of metoprolol, propranolol, ICI 118551 (beta 2 -receptor antagonists), milrinone (phosphodiesterase inhibitor), levosimendan or saline (control) before induction of TS with isoprenaline. In one additional group, high dose of milrinone was administered alone. We measured invasively blood pressure and heart rate over a period of 90 min. Cardiac function and morphology were evaluated with high-resolution echocardiography. Results Milrinone alone induced apical ballooning similar to isoprenaline. Pretreatment with propranolol and metoprolol but not with ICI 118551 attenuated takotsubo-like akinesia in a dose-dependent manner. Pretreatment with metoprolol decreased mortality. Pretreatment with levosimendan resulted in higher incidence of apical ballooning while pretreatment with milrinone did not change the degree of akinesia. Conclusion The phosphodiesterase inhibitor milrinone induces takotsubo-like dysfunction in the absence of exogenous catecholamines. This finding challenges the concept that high levels of circulating catecholamines or excessive stimulation of adrenergic receptors are necessary for the development of takotsubo syndrome. Our study provides experimental evidence for the concept of avoidance of inotropes and that selective beta 1 -blockade may be beneficial in the treatment of TS-patients. Highlights • Cardiostimulants exacerbate whereas cardiodepressants attenuate isoprenaline-induced takotsubo-like cardiac dysfunction in rats. • Milrinone administration can induce takotsubo-like dysfunction in rats without concomitant administration of catecholamine. • High levels of circulating catecholamine may not be necessary for the development of takotsubo. [ABSTRACT FROM AUTHOR]

In recent years, the development market for low-cost nanosatellites has grown considerably. It has been made possible due to the availability of low-cost launch vectors and the use of "commercial off-the-shelf components" (COTS). The satellite design standardization has also helped a great deal to encourage subsystem reuse over a number of space missions. This has created numerous opportunities for small companies and universities to develop their own nanosatellite or satellite subsystems. Most COTS components are usually not space qualified. In order to make them work and withstand the harsh space environment, they need extra effort in circuit redesign and implementation. Also, by adopting the modularity concept and the design reuse method, the overall testing and nonrecurring development cost can be significantly reduced. This can also help minimize the subsystem testing times. The RF front-end design presented in this paper is also considered one of the better and feasible choices based on the above approach. It consists of an S-band transceiver that is fully implemented using COTS components. In the transmit chain, it is comprised of the transmitting CC2510 RF matching network and a power amplifier (PA) with an RF output power of up to 33 dBm which connects to an antenna using two RF switches. The receive chain starts from the antenna that is connected through two RF switches to the low-noise amplifier (LNA) that further connects to the receiving CC2510 via the RF matching network. The receiver sensitivity is -100 dBm. This is a half-duplex system using the same antenna for transmitting and receiving. The receiver and transmitter chains are isolated together using two RF switches which together provide an isolation of up to 90 dB at 2.4 GHz. The concept behind using two RF switches is to provide better isolation from the transmit chain to the LNA. The matching network of CC2510 has been designed in a symmetric fashion to avoid any delays. All the RF COTS used have been selected according to link budget requirements. The LNA, PA, and RF switches were tested individually for compliance. The passive components used in the overall design of the matching network are chosen on the basis of minimum dimension, least parasitic behaviour, and guaranteed optimum RF matching. Also, the RF COTS used are non-CMOS which makes them more robust against space radiations associated with the LEO environment and enables them to provide a radio communication data rate of up to 500 kbps in both uplink and downlink. The vacant spaces on the implemented PCB are shielded with a partial ground plane to avoid RF interference. [ABSTRACT FROM AUTHOR]

The Electric Power System (EPS) and attitude control system (ACS) are the essential components of any satellite. EPS and ACS efficiency and compactness are substantial for the proper operation and performance of the satellite's entire mission life. So, realizing the significance of EPS and ACS subsystems for any satellite, they have been assimilated and developed in modular forms focusing on efficiency and compactness. The EPS is comprised of three modules called the solar panel module (SPM), power conditioning module (PCM), and power distribution module (PDM) while the ACS has an embedded magnetorquer coil. For compactness and miniaturization purposes, the magnetorquer coil is embedded inside the SPM. The components used are commercial off-the-shelf (COTS) components emphasizing on their power efficiency, small dimensions, and weight. Latch-up protection systems have been designed and analyzed for CMOS-based COTS components, in order to make them suitable for space radioactive environment. The main design features are modularity, redundancy, power efficiency, and to avoid single component failure. The modular development of the EPS and ACS helps to reuse them for future missions, and as a result, the overall budget, development, and testing time and cost are reduced. A specific satellite mission can be achieved by reassembling the required subsystems. [ABSTRACT FROM AUTHOR]

Spacecrafts need to maneuver their solar panels towards the sun and antennas towards the ground station for maximum solar power harvesting and communication with the ground station. For tracking purpose, usually magnetorquer rods, reaction wheels and permanent magnets are used, but they are heavier, expensive, and occupy extra space on the spacecraft. Keeping in mind the dimension, budget and mass constraints of small satellites, a system compatible with small satellite is worth consideration. Consequently, this paper focuses on designing and analyzing a solar panel module with embedded Air-Coil. Such an Air-Coil is an innovative idea for the replacement of heavier, bulky and expensive attitude control systems. The proposed Air-Coil is integrated in the internal layers of an eight layers solar panel PCB module. Complete degradation analyses of the solar panel have been done to ensure that it will meet the satellite power requirements at BOL (beginning of life) and EOL (end of life). The proposed embedded Air-Coil has been analyzed for the generated magnetic moment, resultant torque, power consumption and temperature increase of the complete solar panel unit. A steady state thermal model is proposed to measure the thermal resistance between top and bottom layers of the solar panel module, which gives an idea about the heat trapped inside the solar panel module. The designed embedded Air-Coil is fully reconfigurable where coil in each layer can be operated as a separate coil. The four coils in different layers can be attached or detached through switches in different configurations i.e. single coil, four in series, four in parallel, and their hybrid combinations. The analyses of power consumption, heat dissipation, temperature rise, magnetic moment and torque generation by different configurations of the designed Air-Coil have been performed. The generated magnetic moment is very high i.e. around 12Am2, which is enough to rotate a microsatellite by 90° in 200s. The efficacy of the proposed module is significantly higher than the already available systems with respect to mass, price, power dissipation, heat generation, and dimension. [ABSTRACT FROM AUTHOR]

Interaction of cationic surfactants, tetradecyltrimethylammium bromide (TTAB) and tetradecyltrimethylammonium chloride (TTAC) with anionic dye, tartrazine in aqueous solution has been investigated employing conductometric technique. The free energy of transfer of hydrophobic chain, ΔGHPo, surface contribution, ΔGSo and their transfer values, ΔGHP;tro and ΔGS;tro, free energy, ΔGmo, enthalpy, ΔHmo, and entropy, ΔSmo of micellisation have been calculated. A marked decrease in the critical micelle concentration for TTAB compared to TTAC indicates dramatic role of the smaller counterion Br- over the bigger counterion Cl-. Formation of dye-surfactant ion-pairs which behave as nonionic surfactant has been proposed. Higher negative ΔGHPo and positive ΔGSo values for TTAB than TTAC are attributed to difference in the size and nature of the counterions Br- and Cl-. Negative ΔGmo and ΔHmo values clearly suggest that micellisation of TTAB and TTAC is thermodynamically spontaneous and exothermic in nature. As (-TΔSmo) » ΔHmo), it suggests that the process of micellisation is entropy dominated for the two surfactants. [ABSTRACT FROM AUTHOR]

Reliable biomass and carbon stock estimation are central to obtain reference levels for quantifying carbon emissions. Forest inventory data combined with remote sensing data provides opportunities to map and monitor forest areas at various spatiotemporal scales. The current research is a pilot study focussed on the biomass and carbon estimation and mapping of subtropical scrub forests of Khanpur range, Haripur Forest Division, Pakistan considering 20 inventory plots using Sentinel-2A and Landsat-8 data. Six forest areas (Garamthun, Chhoi, Moharagutta, Sanaba, Dobandi and Saradana) were considered covering a total area of 697.3 ha. Average biomass of the assessed plots was 104.6 t/ha and mean carbon stock was 49.7 t/ha. Garamthun forest had the highest values for both biomass (187.30 t/ha) and carbon (87.98 t/ha) followed by Choi with 148.22 t/ha of biomass and 69.6 t/ha carbon respectively. The total estimated carbon stock for these six forest types was 43570.9 t. The biomass was then correlated with spectral indices computed from Sentinel 2 image (NDVI, SAVI, DVI, PVI and MSAVI). NDVI performed significantly well among five other indices with the values of R2 of 0.81 followed by 0.7 and 0.58 for SAVI and DVI respectively. PVI and MSAVI responded poorly to biomass as compared to the other indices with the value of R2 of 0.20 and 0.11 respectively. Spatial distribution of biomass was mapped using NDVI, which was selected as the best model based on the values of R2. Further, Landsat-8 was also used and the similar five indices were derived for Landsat-8 imagery. Finally, both the indices derived from Sentinel-2A and Landsat-8 were compared. Scrub forests of Khanpur showed the largest potential for carbon sequestration and storage. It is suggested that this method is not only used for the Haripur district in Khyber Pakhtunkhwa, whose forest division extends merely over the area of 42491 ha; rather it should be applied to the entire forest area of Pakistan for national forest inventory. The research concluded that Sentinel 2 has the best combination of spectral capabilities and broad spectrum of applicability. [ABSTRACT FROM AUTHOR]

The paper discusses the comparison of different shapes of embedded air coils for the attitude control of small satellites. Various systems are available in the market for the attitude control of small satellites such as reaction wheels, permanent magnets, magnetic rods and thrusters. The available systems have large size, heavier weight and relatively higher power consumption. A miniaturized system with less power consumption and heat dissipation is required that can provide the anticipated torque. This paper focuses on the design and comparison of square and circular air coils embedded in four internal layers (i.e. 2nd, 3rd, 4th, and 5th) of the eight layer CubeSat power management tile (CubePMT) PCB. Each layer has 50 turns of copper traces and four layers have a total of 200 turns. The four embedded coils are reconfigurable and can be connected in different configurations (single, series, parallel, and hybrid) through switches. The two shapes are compared on the basis of dipole moment, torque generated, power dissipated, time of rotation and thermal heat generation. [ABSTRACT FROM AUTHOR]

Spectroscopic and conductometric approach was employed to study the effect of aromatic amino acid-tyrosine on the micellisation of hexadecyltrimethylammonium bromide and sodium dodecyl sulphate in aqueous medium. Tyrosine was used as an additive as well as a probe while recording the UV-visible spectrum. A simple experiment was performed were the conductivity and UV-visible spectrum of amino acid was utilised to determine the effect of increasing amphiphile concentration. The critical micelle concentration and various thermodynamic parameters such as Gibbs free energy of micellisation,, enthalpy of micellisation,, entropy,, Gibbs free energy of transfer values,, hydrophobic free energy,, free energy associated with surface contribution,, etc. were calculated to find the effect of this amino acid on the solubilisation, interaction, and aggregation process in aqueous medium. [ABSTRACT FROM PUBLISHER]

The interaction of cresol red (CR) with cetylpyridinium bromide (CPB), sodium dodecyl sulphate (SDS), and Triton X-100 (TX-100) was studied in aqueous solutions employing conductometric, tensiometric, and spectroscopic methods. Various micellar and interfacial parameters were calculated in absence and in presence of CR. The interactions suggest the formation of a CR-CPB adduct, an association of CR with the micelle of TX-100 while no adduct is formed between CR and SDS. Appreciably low critical micelle concentration, CMC value of TX-100 compared with those of CPB and SDS in pure water and drastic reduction of CMC of CPB (about one-twelfth of its value in pure water) than SDS and TX-100 in the presence of CR were observed. Higher negative values of Gibbs free energy of micellization, ΔGm0, for all the three surfactants indicate that micellization process is spontaneous. The values of maximum surface excess concentration, Γmax, and minimum area per molecule, Amin, suggest that in the presence of CR, the air-solution interface is closely packed and the orientation of surfactant molecules is almost perpendicular to the surface. UV-visible spectra suggest the formation of ion-pair complex between the dye CR and the monomers of CPB in the pre-micellar region, while above the CMC a breaking up of the ion-pair complex takes place and the dye is solubilized in the micelles of CPB. In the case of SDS the absorption spectra indicate weak interaction between CR and SDS molecules formation of H-bonding, short range dispersive forces, and hydrophobic interactions between CR and TX-100 molecules in the solution. [ABSTRACT FROM AUTHOR]

Interaction of imidazolium based surface-active ionic liquid (SAIL), 1-decyl-3-methylimidazolium chloride [C 10 mim][Cl], with cationic surfactant cetrimide (CET) has been studied by using conductometric, tensiometric, and spectroscopic methods in pure water and in presence of diethylene glycol (DEG)–water binary mixtures. Addition of DEG has marked effect on the thermodynamic and aggregation behavior of these studied systems. From conductometric approach various parameters have been calculated such as critical micelle concentration, ( cmc ), micellar mole fraction, X 1 , of component 1 (CET), micellar interaction parameter, β , activity coefficients ƒ 1 and ƒ 2 of component 1 and component 2 (SAIL), standard Gibbs energy of micellization (Δ G m 0 ), and degree of counter ion dissociation ( g ). Rubingh's non-ideal solution theory confirms the attractive and non-ideal behavior among the surfactant molecules in the mixed micelles. From the tensiometric studies different parameters such as surface tension reduction efficiency ( pC 20 ), maximum surface excess concentration ( Γ max ), minimum area per surfactant molecule ( A min ) and standard Gibbs free energy of adsorption Δ G ad 0 at the interface were evaluated. The packing parameters of amphiphiles in the micelles, P , volume contribution of the hydrophobic chain, v , and its effective length, l C have also been evaluated for the pure and mixed systems. The micelles/mixed micelles formed have spherical geometry. Cresol red, an anionic dye, was used as a probe for UV–visible spectra of pure and mixed systems, which supports the role of SAIL in the mixed micellization process. [ABSTRACT FROM AUTHOR]

The interaction of cationic surfactants, namely dodecyltrimethyl ammonium bromide (DTAB) and cetrimide (CET) with tricyclic antidepressant drug, nortryptyline hydrochloride (NH) (used for depression related illness, nocturnal enuresis, chronic fatigue syndrome, irritable bowel syndrome, chronic pain or neuralgia, and migraine) were studied employing conductometric and tensiometric techniques. From these techniques, various micellar and interfacial parameters such as critical micelle concentration, cmc, micellar mole fraction, X 1 , micellar interaction parameter, β , activity coefficients ƒ 1 and ƒ 2 in the mixed micelles, excess Gibbs free energy of micellization, Δ G ex 0 , standard Gibbs free energy, Δ G m 0 , surface excess concentration, Г max , minimum surface area per molecule, A min , and standard Gibbs free energy of adsorption Δ G ad 0 at the interface were evaluated. In addition to this, various other parameters such as, packing parameters of amphiphiles in the micelles, P , volume contribution of the hydrophobic chain, v , and its effective length, l C have also been calculated for pure and mixed systems. From packing parameters it was confirmed that the micelle/mixed micelles formed have spherical geometry. The Δ G m 0 and Δ G ad 0 values for all studied systems were found to be negative and this shows that both micellization as well as adsorption processes are energetically favorable. Furthermore, the values of Δ G ad 0 were more negative than their corresponding Δ G m 0 , showing that work is done in transferring the amphiphilic monomers from interface to the micellar stage across the aqueous solution to form micelles. The interaction parameters, β , calculated by using regular solution theory were also observed to be negative suggesting synergistic interaction for the proposed mixed systems. [ABSTRACT FROM AUTHOR]

Introduction Rap1, a member of Ras superfamily of small GTP-binding proteins, is involved in cardiovascular biology in numerous ways. It is an evolutionary conserved regulator of adhesion, polarity, differentiation and growth. Aims Our aim was to analyze Rap1-activated rat bone marrow mesenchymal stem cells ( MSCs) for their potential role in adhesion and cardiac differentiation. Methods Myocardial infarction ( MI) was produced in Sprague Dawley ( SD) rats through occlusion of the left anterior descending coronary artery. MSCs were treated with 8- pCPT-2′-O-Me- cAMP ( CPT) to activate Rap1. Normal (untreated) and CPT-treated MSCs were transplanted through intramyocardial injection in respective groups. Cardiac function was assessed by echocardiography at 2 and 4 weeks after cell transplantation. Histological analysis was performed to observe changes at tissue level. Results Homing of CPT-treated MSCs was significantly (*** P<.001) higher as compared to normal MSCs in the infarcted hearts. This may be due to increase in the gene expression of some of the cell adhesion molecules as evident by qRT- PCR analysis. Significant (*** P<.001) improvement in the restoration of heart function in terms of left ventricular diastolic and systolic internal diameters ( LVIDd, LVIDs), % ejection fraction, % fraction shortening and end-systolic and end-diastolic volumes were observed in CPT-treated MSCs as compared to the MI model. Histological analyses showed significant (*** P<.001) reduction in scar formation in the CPT-treated group. Differentiation of treated MSCs into functional cardiomyocytes was evident through immunohistochemical staining. LV wall thickness was also preserved significantly (*** P<.001). Blood vessel formation was more pronounced in CPT-treated group although both cell therapy groups showed significant increase as compared to MI model. Conclusion Our findings showed that pharmacological activation of Epac-Rap1 improves cardiac function through better survival, adhesion and differentiation of transplanted cells. Transplantation of these MSCs in the infarct area restored functional myocardium. [ABSTRACT FROM AUTHOR]

Physicochemical properties of aqueous surfactant solutions can be suitably modified by the addition of room temperature surface-active ionic liquids (SAILs). As green solvents, these SAILs are used as the ideal additives for modifying the aqueous surfactant properties. Such mixed surfactant + SAIL systems in aqueous solutions find enormous applications in several technological fields. The changes in the micellar behavior of cationic surfactants cetylpyridinium chloride (CPC) and cetylpyridinium bromide (CPB) have been investigated in the presence of SAIL 1-decyl-3-methylimidazolium chloride [C 10 mim][Cl] employing conductometric and tensiometric methods. Micellar and interfacial parameters such as critical micelle concentration, cmc micellar mole fraction, X 1, of component 1 (CPC/CPB), micellar interaction parameter, β , activity coefficients ƒ 1 and ƒ 2 of component 1 and component 2 (SAIL) in the mixed micelles, excess Gibbs free energy of micellization, ΔG ex 0 , standard Gibbs free energy, ΔG mic 0 , enthalpy, ΔH mic 0 , and entropy, ΔS mic 0 of micellization, surface excess concentration, Г max , minimum surface area per molecule, A min , and standard Gibbs free energy of adsorption ΔG ad 0 at the interface were evaluated. In addition, packing parameters of amphiphiles in the micelles, P , volume contribution of the hydrophobic chain, v , and its effective length, l C have also been evaluated for the pure and mixed systems. The interactions between CPC/CPB and SAIL in the mixtures are found to be non-ideal and synergistic, and that mixed micelles are richer in CPC/CPB monomers. Of the several interactive interactions, hydrophobic interaction seems to be dominant between the components of the mixed systems. Adsorption of SAIL molecules at air-solution interface is found to be richer in SAIL than CPC/CPB molecules, which is also supported by the higher negative ΔG ad 0 values than ΔG mic 0 values. The micelles/ mixed micelles formed have spherical geometry. [ABSTRACT FROM AUTHOR]

Aims The aim of this study is to determine if preconditioning of bone marrow derived mesenchymal stem cells (MSCs) with 2,4-dinitrophenol (DNP) improves survival of transplanted stem cells in a rat model of myocardial infarction (MI), and to asses if this strategy has measurable impact on cardiac function. Main methods MSCs were preconditioned with DNP. In vitro cell adhesion assay and qRT-PCR were performed to analyze the expression of genes involved in cardiomyogenesis, cell adhesion and angiogenesis. MI was produced by occlusion of left anterior descending coronary artery. One million cells were transplanted by intramyocardial injection into the infarcted myocardium. Echocardiography was performed after two and four weeks of cellular transplantation. Hearts were harvested after four weeks and processed for histological analysis. Key findings DNP treated MSCs adhered to the surface more ( p < 0.001) as compared to the normal MSCs. Gene expression levels were significantly upregulated in case of DNP treatment. The number of viable MSCs was more ( p < 0.001) in animals that received DNP treated MSCs, leading to significant improvement in cardiac function. Histological analysis revealed significant reduction in scar formation ( p < 0.001), maintenance of left ventricular wall thickness (p < 0.001), and increased angiogenesis ( p < 0.01). Significance The study evidenced for the first time that MSCs preconditioned with DNP improved cardiac function after transplantation. This can be attributed to improved survival, homing, adhesion, and cardiomyogenic and angiogenic differentiation of DNP treated MSCs in vivo. [ABSTRACT FROM AUTHOR]

• Propose multi-objective optimization and decision-making framework. • Considers risk attitudes of decision-makers under uncertain consequences. • Assess consequences by establishing surrogate-based Gaussian process models. • Illustrates the framework on a community building portfolio. The performance of community building portfolios under extreme events is increasingly been assessed in terms of socioeconomic and environmental consequences. These multiple consequences are expensive to be evaluated, uncertain in nature, and it requires an efficient optimization and decision-making tool for performance enhancements on a community level. In this paper, an efficient multi-objective performance-based optimization and decision-making framework is proposed to assess and enhance the performance of community building portfolios under uncertain consequences. The proposed approach includes (1) performance-based black-box to evaluate the socioeconomic and environmental consequences given community building portfolios by considering all the possible hazard scenarios, (2) surrogate-based multi-objective optimization to efficiently approximate the Pareto-optimal solutions by exploiting Gaussian process models, spectral sampling, non-dominated crowding and sorting, and hyper improvements, among others, and (3) utility theory-based decision-making of a community building portfolios considering multiple performance-objectives over an entire hazard curve and under different risk attitudes. The proposed methodology is illustrated on community building portfolio under seismic hazards of varying intensities and occurrence probabilities. A performance-based black box is utilized along with a proposed optimization technique to assess community-level consequences. Finally, the utility for Pareto-optimal solutions is assessed and discussed for possible performance enhancements and decision-making. [ABSTRACT FROM AUTHOR]

Conductometric and surface tension techniques were employed to study the different mole fractions of nonionic surfactants (TX-100 and Brij-35) with cetrimide. The standard Gibbs energies of micellization ( $$\Delta G_{\text{m}}^{0}$$ ) and the Gibbs energies of transfer ( $$\Delta G_{\text{trans}}^{0}$$ ) in the mixture of surfactants were also calculated; the micellization becomes more spontaneous on increasing the amount of nonionic surfactants in the mixture. It was observed that the values of excess surface concentration (Γ) in surfactant mixtures decrease in comparison to the pure surfactants but the values of minimum area per surfactant molecule ( A) increase in surfactant mixtures than in the pure ones. It was also observed that the values of the interaction parameter ( β) are negative at all mole fractions. A gradual decrease in β with temperature is observed indicating the synergism between the two components and is attributed to the decrease in the electrostatic repulsion between the charged heads of the cationic surfactant as the nonionic surfactant is being intercalated into the micelle. The activity coefficients were found out to be less than unity confirming nonideality of the system and the negative values of excess free energy of mixing confirm that the mixed micelles formed were stable. [ABSTRACT FROM AUTHOR]

Conductivity measurements were employed to investigate Kraft temperature ( T K ) of aqueous solution of hexadecylpyridinium bromide (HPyBr) and HPyBr + glycine with added counter-ions. The pseudophase ion exchange model was adopted for HPyBr in pure water, glycine (Gly) and potassium bromide (KBr). The T K values for HPyBr increase with the increase in concentration of Gly and KBr. However, the experimental results show that the degree of counter-ion dissociation or ionization (α) remains nearly constant as the total surfactant concentration or counter-ion concentrations of salt are varied at the slower rate of micellar growth. Although the (α) is dependent on micellar shapes and changes as the micellar shape changes. The T K measurements for ionic micelles can be used to estimate counter-ion dissociation (α). The T K increase with increase in the counter-ion concentration because the solubility of surfactant is reduced at faster rate than critical micellar concentration (CMC). Kraft temperature measurements were employed to find the interaction between HPyBr and Glycine. [ABSTRACT FROM AUTHOR]

Krafft temperature ( T k ) and thermodynamics of micellization of Hexadecylpyridinium chloride (HPyCl) and Hexadecylpyridinium bromide (HPyBr) were carried out in the absence and in the presence of amino acids-glycine, diglycine and triglycine. Thermodynamic parameters of micellization — Gibbs free energy of micellization, enthalpy, entropy, free energy related with hydrophobic part and surface contribution were calculated from the specific conductance data. Transfer values of Gibbs free energy and enthalpy were also calculated. T k of HPyCl and HPyBr were determined in aqueous as well as in presence of aqueous-glycine, diglycine and triglycine. Effect of polar head group, counter-ions, additives, T k , and micellization parameters on micelle formation of the surfactants are the main points taken into consideration while explaining and interpreting the results to get an insight into the interactions of these additives with the cationic surfactants. [ABSTRACT FROM AUTHOR]

Densities $$\rho $$ and ultrasonic speeds u for pure diethylene glycol, 1-butanol, 2-butanol, and 1,4-butanediol and for their binary mixtures over the entire composition range were measured at 298.15 K, 303.15 K, 308.15 K, and 313.15 K. Using these data, the excess molar volumes, $$V^{E}_\mathrm{m}$$ , deviations in isentropic compressibilities, $${\varDelta }k_{s}$$ , apparent molar volumes, $$V_{\phi ,i} $$ , partial molar volumes, $$\overline{V}_{m,i} $$ , and excess partial molar volumes, $$\overline{V}_{m,i}^E $$ , have been calculated over the entire composition range, and also the excess partial molar volumes of the components at infinite dilution, $$\overline{V}_{m,i}^{E,\infty }$$ have been calculated. The excess functions have been correlated using the Redlich-Kister equation at different temperatures. The variations of these derived parameters with composition and temperature are presented graphically. [ABSTRACT FROM AUTHOR]

A reconfigurable magnetorquer coil has been designed and implemented for the CubeSat power management, attitude determination, and control tile (CubePMT) module of CubeSat-standard nanosatellites. Magnetorquer coil is a good choice for attitude control and stabilization of nanosatellites. The goal of this work is to provide CubeSat with a magnetorquer coil, which has small dimensions, low weight, and low heat dissipation. The designed magnetorquer coil is reconfigurable and integrated within the printed circuit board internal layers, occupying no extra space on CubeSat. Coils in each layer are treated separately and can be attached and detached through straps. Changing the arrangement of these straps, one can use 1, 2, 3, or 4 coils in series, parallel, or any hybrid combination. This reconfigurable design provides an option for generating different amounts of magnetic moment and resultant torque to stabilize and rotate the satellite. Emissivity of the CubePMT module was found through lab experiments. Power dissipation and the corresponding temperature increase of the CubePMT module are evaluated by thermal modeling. [ABSTRACT FROM PUBLISHER]

Synergistic interactions between cetrimide and sodium dodecyl sulfate (SDS) were studied at three different temperatures. Aqueous solutions of pure cetrimide, SDS and their mixtures were investigated conductometrically. The mixed surfactants exhibited nonideal behavior as the CMCs are less than the ideal CMC values calculated by using Clint's equation. In addition, Rubingh's model was used and various parameters such as the activity coefficients f and f, micelllar mole fraction, X, interaction parameter, β, excess Gibbs energy and enthalpy of mixing, $$ \Delta G_{\text{ex}} $$ and $$ \Delta H_{\text{ex}} $$ , respectively, were calculated. The values of f, f, and β indicate strong interaction between cetrimide and SDS and the interaction increases with increasing mole fraction of SDS in the mixture. Negative β values and | β| > |ln( CMC /CMC)| clearly confirm synergism in the surfactant mixture. Negative $$ \Delta G_{\text{ex}}^{{}} $$ and $$ \Delta H_{\text{ex}}^{{}} $$ values of the mixed systems at different bulk mole fractions also reflect the behaviors of β and f. The values of the standard Gibbs energy and enthalpy of mixed micelle formation are negative, suggesting that micellization is thermodynamically favorable and exothermic in nature. Larger positive contributions of the entropic component, $$ T\Delta S_{\text{m}}^{ 0} $$ , than the enthalpic component, $$ \Delta H_{\text{m}}^{ 0} $$ , to $$ \Delta G_{\text{m}}^{ 0} $$ are ascribed to the destruction of the structured water surrounding the hydrophobic groups of the surfactants when these groups are transferred from the bulk into the interior of the micelle. [ABSTRACT FROM AUTHOR]

By virtue of their complete spin polarization at the Fermi level, two-dimensional (2D) magnetic half-metallic materials are emerging as one of the latest wonder building blocks for spintronic applications. Using first-principles calculations, we explored how vacancy defects affect the electronic structure and magnetic properties of CrSI semiconductor monolayer. Our results indicate that the magnetic semiconductor monolayer becomes metallic with the presence of single Cr vacancies, V Cr , or paired vacancies made up of Cr and nearby S atoms, V Cr-S , while by introducing V S , V I , V Cr-I and V S-I vacancies, the monolayer becomes a half-metallic ferromagnet with Curie temperature T C above room temperature. Compared with the pristine case that exhibits an intrinsic in-plane magnetic anisotropy with an easy axis along the [100] direction, the six types of vacancies considered in this study either enhance the in-plane anisotropy or switch it to out-of-plane. Our work implies that vacancy engineering could be a viable approach for achieving both half-metallicity and perpendicular magnetic anisotropy in structurally similar magnetic semiconductor monolayers as well as in relevant designer van der Waals heterostructures for 2D spintronic applications. • Pristine CrSI monolayer is a 2D magnetic semiconductor with a total magnetic moment M tot of 3.000 μ B per unit cell. • Pristine CrSI monolayer has Curie temperature well above room temperature. • We predict vacancy-induced half-metallicity in magnetic CrSI semiconductor monolayer. • The six types of vacancies considered can either enhance the in-plane anisotropy or switch it to out-of-plane. [ABSTRACT FROM AUTHOR]

Various preconditioning strategies influence regeneration properties of stem cells. Preconditioned stem cells generally show better cell survival, increased differentiation, enhanced paracrine effects, and improved homing to the injury site by regulating the expression of tissue-protective cytokines and growth factors. In this study, we analyzed gene expression pattern of growth factors through RT-PCR after treatment of mesenchymal stem cells (MSCs) with a metabolic inhibitor, 2,4 dinitrophenol (DNP) and subsequent re-oxygenation for periods of 2, 6, 12 and 24 h. These growth factors play important roles in cardiomyogenesis, angiogenesis and cell survival. Mixed pattern of gene expression was observed depending on the period of re-oxygenation. Of the 13 genes analyzed, ankyrin repeat domain 1 (Ankrd1) and GATA6 were downregulated after DNP treatment and subsequent re-oxygenations. Ankrd1 expression was, however, increased after 24 h of re-oxygenation. Placental growth factor (Pgf), endoglin (Eng), neuropilin (Nrp1) and jagged 1 (Jag1) were up-regulated after DNP treatment. Gradual increase was observed as re-oxygenation advances and by the end of the re-oxygenation period the expression started to decrease and ultimately regained normal values. Epiregulin (Ereg) was not expressed in normal MSCs but its expression increased gradually from 2 to 24 h after re-oxygenation. No change was observed in the expression level of connective tissue growth factor (Ctgf) at any time period after re-oxygenation. Kindlin3, kinase insert domain receptor (Kdr), myogenin (Myog), Tbx20 and endothelial tyrosine kinase (Tek) were not expressed either in normal cells or cells treated with DNP. It can be concluded from the present study that MSCs adjust their gene expression levels under the influence of DNP induced metabolic stress. Their levels of expression vary with varying re-oxygenation periods. Preconditioning of MSCs with DNP can be used for enhancing the potential of these cells for better regeneration. [ABSTRACT FROM AUTHOR]

The densities, ς and viscosities, η of glycine (Gly), L-alanine (Ala), L-phenylalanine (Phe) and glycylglycine (Gly-Gly) in aqueous Triton X-100 (TX-100) solutions have been measured as a function of amino acid/peptide concentration at 298.15, 303.15, 308.15 and 313.15 K. The experimental data have been utilized to evaluate various thermodynamic parameters, viz., apparent molar volumes, V2, partial molar volumes at infinite dilution, V20, partial molar isobaric expansibilities, φE0, partial molar volumes of transfer, ΔtrV20 and A and B-coefficients of viscosity, respectively. The hydration numbers have also been calculated. The results have been discussed in terms of interactions taking place in the present systems. The structure-making/-breaking ability of the solute (amino acid/peptide) in the presence of surfactant, Triton X-100 has also been considered. [ABSTRACT FROM AUTHOR]

This is the 12th in a series of articles exploring international trends in health science librarianship. This issue describes developments in health science librarianship in the first decade of the 21st century in South Asia. The three contributors report on challenges facing health science librarians in India, Pakistan and Sri Lanka. There is consensus as to the need for education, training and professional development. Starting in the next issue, the focus will turn to Africa, starting with countries in southern Africa. JM [ABSTRACT FROM AUTHOR]

To alter the physicochemical properties of ILs with green cosolvents, molecular level understanding of the resultant mixtures is hotbed of the current research. In the present study, changes in the physicochemical properties of the IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf 2 N]) on the addition of different polyethylene glycols (PEGs) (average MW 200, 400, 600, and 1500) by means of solvatochromic probes are investigated. The addition of the PEGs to IL [bmim][Tf 2 N] changes the physicochemical properties of the solvent mixtures in unusual and favorable fashion. The response of the solvatochromic probes Reichardt dye 33 and Nile Red hints about the “hyperpolarity” of the IL + PEG mixtures which is rare in the literature. The Kamlet–Taft parameters, hydrogen bond donor ability (HBD) ( α ), hydrogen bond acceptor ability (HBA) ( β ), and dipolarity/polarizability ( π* ) display nonideality, and show strong and unusual “hyperpolarity” behavior on the addition of PEGs to [bmim][Tf 2 N]. A solvent–solvent along with solute–solvent interaction hypothesis is proposed to explain the “hyperpolarity” of the mixtures. Further, the solvation models are used to delineate the solute–solvent/solvent–solvent interactions present in the binary mixtures. Combined nearly ideal binary solvent/Redlich–Kister (CNIBS/R–K) equation was demonstrated to predict the solvatochromic parameters satisfactorily. [ABSTRACT FROM AUTHOR]

Interactions between the cationic surfactant cetyltrimethyl ammonium bromide, dimethylsulphoxide and lauric acid, have been studied in detail using volumetric and viscometric techniques. The critical micelle concentration (cmc) values have been determined using two different methods. The experimental data have been correlated against temperature and concentration using standard relations. From the density of the surfactant, the change of the apparent molar volumes at infinite dilution, $$ V_{\phi }^{\text{o}} $$ , apparent molar volumes at the cmc, $$ V_{\phi }^{\text{cmc}} $$ , and apparent molar volumes upon micellization, $$ \Delta V_{\phi }^{\text{m}} $$ , have been calculated. The viscosity data have been analyzed by means of the Jones-Dole equation in the pre-micellar region and the Einstein equation in the post-micellar region. The values of Falkenhagen coefficient and Jones-Dole coefficient thus obtained are used to interpret the solute-solute interactions in the pre-micellar region whereas Einstein's equation is used to explore solute-solvent interactions in post micellar regions. Transition-state theory was applied to obtain the activation parameters of viscous flow, i.e., Gibbs energy of activation $$ \Delta G^{\text{o*}} $$ , per mole of solvent and solute. Moreover, the enthalpy $$ \Delta H^{\text{o*}} $$ and entropy of activation of viscous flow $$ \Delta S^{\text{o*}} $$ were computed in the pre-micelle regions. The obtained results indicate that the cmc strongly depends on the composition of the mixture. The results have been interpreted in the light of various interactions occurring among the components of the mixtures under the applied experimental conditions. [ABSTRACT FROM AUTHOR]

The critical micelle concentration (CMC) of sodium dodecyl sulphate (SDS) in pure water and in the presence of amino acids (0.01, 0.02 and 0.03 mol kg−1), L-valine (Val) and L-leucine (Leu) was determined from conductometric and fluorometric methods using pyrene as luminescence probe. Depression in the CMC at low concentration of amino acids is attributed to the increased hydrophobic–hydrophobic interaction between the non-polar groups of the surfactant, while, at high concentration, amino acids bind strongly with the anion, DS−, head groups of SDS, thereby, delaying the micelle formation, resulting in increased CMC. A pronounced decrease in the CMC, while a marked increase in λ0+, with decrease in the solvated radius (rather than crystal radius) of the counterions is observed. Negative values of ΔG0mand ΔH0mindicate that micellisation of SDS in the presence of amino acids is thermodynamically spontaneous and exothermic. Highest negative value of ΔH0min 0.01 m Val, with lowest CMC value, shows that 0.01 m aqueous Val is the most suitable medium favouring the micellisation of SDS. Decrease inI1/I3from Val to Leu confirms the relative hydrophobicity of two amino acids. The observed values of the packing parameter,P, of SDS in water and in aqueous amino acids suggest that micelles formed are spherical in nature. [ABSTRACT FROM PUBLISHER]

Abstract: Interaction of anionic dye, cresol red (CR), with cationic surfactants, dodecyltrimethylammonium bromide (DTAB) and cetyltrimethylammonium bromide (CTAB), in aqueous solution in the submicellar and micellar concentration ranges has been investigated by using thermodynamic and spectroscopic methods. The equilibrium model has been used to calculate the standard free energy (∆G m o), enthalpy (∆H m o), and entropy (∆S m o) of micelle formation. The increase in the critical micelle concentration (cmc) with rise in temperature is attributed to the disruption of the structured water surrounding the hydrophobic groups of the surfactants. A marked decrease in the cmc is observed as the number of carbon atoms in the hydrophobic group increases from DTAB to CTAB. Higher values of the degree of ionization (α) of the micelles of DTAB and CTAB are obtained in the presence of CR than in its absence. Negative values of ∆G m o and ∆H m o for the surfactants in aqueous and in aqueous CR solutions show that the process of micellization is thermodynamically spontaneous and exothermic. The values of −T∆S m o are much higher than the ∆H m o values, indicating that the micellization process is governed primarily by the entropy gain associated with it. The heat capacity of micellization (ΔC p,m ο ) is negative which is mainly due to the change in the exposure of the hydrophobic groups to the water molecules. UV–visible spectra suggest interaction between dye and surfactant monomers forming ion-pair complex in the pre-micellar region whereas above the cmc solubilization of dye in the micelle dominates over ion-pair formation. [Copyright &y& Elsevier]

After deployment from a rocket, a CubeSat is detumbled using magnetorquer rods bringing the norm to the point where the reaction wheels take over to reduce the angular velocity to null. Therefore, utilizing reaction wheels for satellite detumbling at higher initial velocities is vital but they are heavy and occupy significant space on a spacecraft having challenging control. To address this challenge, this paper features a disruptive approach that conducts the control only by the PCB-integrated magnetorquers with various geometries using a diverse non-unity track width ratio. The trace widths are parametrized such that the optimal torque to power dissipation ratio is investigated. The optimizations are then simulated for various geometric distributions and validated through comprehensive measurement setups that establish a framework for selecting the best-case coil configuration according to mission requirements. The detumbling rates of multiple asymmetric coil configurations are compared with the embedded designs in published literature and state of the art. It is found that the proposed asymmetric embedded magnetorquers can detumble the vehicle at high initial angular velocities. Lastly, the simulation results of thermal analysis are validated for selecting the application-specific optimal coils configuration. At the end, the proposed system is compared with the embedded magnetorquers available in the literature and commercial attitude control systems. [ABSTRACT FROM AUTHOR]