The 2021 room-temperature superconductivity roadmap

Designing materials with advanced functionalities is the main focus of contemporary solid-state physics and chemistry. Research efforts worldwide are funneled into a few high-end goals, one of the oldest, and most fascinating of which is the search for an ambient temperature superconductor (A-SC). The reason is clear: superconductivity at ambient conditions implies being able to handle, measure and access a single, coherent, macroscopic quantum mechanical state without the limitations associated with cryogenics and pressurization. This would not only open exciting avenues for fundamental research, but also pave the road for a wide range of technological applications, affecting strategic areas such as energy conservation and climate change. In this roadmap we have collected contributions from many of the main actors working on superconductivity, and asked them to share their personal viewpoint on the field. The hope is that this article will serve not only as an instantaneous picture of the status of research, but also as a true roadmap defining the main long-term theoretical and experimental challenges that lie ahead. Interestingly, although the current research in superconductor design is dominated by conventional (phonon-mediated) superconductors, there seems to be a widespread consensus that achieving A-SC may require different pairing mechanisms.In memoriam, to Neil Ashcroft, who inspired us all.

Efficacy and Safety of Systemic and Locoregional Cisplatin Chronotherapy in Rats with Ovarian Carcinoma

Aim

Alterations in circadian rhythms caused by tumor growth are thought to be clinically relevant as they affect the prognosis and treatment response. We aimed to evaluate the chronotherapeutic approach in rats with ovarian cancer receiving cisplatin intravenously (IV) or with hyperthermic intraperitoneal chemoperfusion (HIPEC) and to assess daily variations in tumor and intestinal epithelium proliferation.

Methods

In the pilot study, we used 12 intact rats and 12 rats with transplantable ovarian cancer, which were euthanized at ZT0 (08:00, lights on), ZT6, ZT12 and ZT18. In the main study, we used 45 rats with transplantable ovarian cancer. Animals were randomized into five groups: control, HIPEC with cisplatin at ZT0 (08:00), HIPEC with cisplatin at ZT12 (20:00), IV cisplatin at ZT0 and IV cisplatin at ZT12. We assessed the proliferation rate of tumor and small intestinal epithelium, apoptosis in small intestinal epithelium, and levels of γ-H2AX (DNA damage/repair marker) in kidneys and liver. Survival was calculated in each group.

Results

Ascitic ovarian cancer disrupted daily variations in intestinal epithelium proliferation and DNA damage/repair in rats. Ovarian carcinoma exhibited no daily variation in mitotic activity. In animals receiving IV cisplatin, massive cell damage in the renal medulla and cystic changes within renal tubules were observed, unlike in rats receiving HIPEC. Tumor mitotic activity was lower in morning-treated groups. The median survival of rats in the control group was 8.5 days (95% CI 6.0–22.0), in HIPEC at ZT0 40.5 days (95% CI 28.0–47.0, p<0.001) and in HIPEC at ZT12 32.0 days (95% CI 28.0–37.0, p<0.001).

Conclusion

In a rat model, ovarian tumor growth disrupted daily variations in intestinal epithelium proliferation and caused genotoxic stress in tumor-free tissues. HIPEC with cisplatin at ZT0 had a better efficacy/toxicity profile than HIPEC with cisplatin at ZT12 and IV administration at both time points.

Aging delay: of mice and men

The evaluation of the safety of a drug in rodents that may be used as geroprotectors is a challenge of current times. In the paper, we discuss approaches to long-term assays for selection of potent aging delay drugs for humans. Priority is given to methods combining evaluation of carcinogenic safety and life-spanning potential. The use of such methods will be time-efficient and economically feasible. (www.actabiomedica.it)

PSYCHOPHYSIOLOGICAL INDICATORS OF FLOW STATE

Aim. The study aims to reveal objective psychophysiological indicators that are related to flow state. Materials and methods. Thirty-one (31) athletes of different competitive levels (20 females and 11 males, mean age 19.1 ± 4.59 years) participated in the study. The dynavision D2 training device was applied for creating optimal flow state conditions during the experiment. Physiological indicators were recorded by the Thought Technology hardware and software system. Heart rate variability, respiration rate (thoracic and abdominal), finger temperature, skin conductance were analyzed. Flow state depth was estimated based on the participants’ answers during the semi-structured interview that followed the experiment. Results. According to the results of the interview, all athletes were divided into two groups: the first group included athletes experiencing flow state (“flow” group), the second group composed of athletes who did not manage to experience flow state (“no-flow” group). When comparing these two groups after the experiment, it was revealed that the first group had higher levels of standard deviations of heart rate compared with the second group. In the first group (flow), the following indicators were significantly higher after the experiment: standard deviation of the RR-intervals (SDRR), skin conductance, and finger temperature. In the second group (no-flow), only skin conductance increased significantly. Conclusion. The results allow us to conclude that the flow state is characterized by a marked increase in the sympathetic nervous system (a higher level of stress compared to the same activity without flow). 

NWChem: Past, present, and future

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

Applying parametric models to survival data: tradeoffs between statistical significance, biological plausibility, and common sense

Parametric models for survival data help to differentiate aging from other lifespan determinants. However, such inferences suffer from small sizes of experimental animal samples and variable animals handling by different labs. We analyzed control data from a single laboratory where interventions in murine lifespan were studied over decades. The minimal Gompertz model (GM) was found to perform best with most murine strains. However, when several control datasets related to a particular strain are fitted to GM, strikingly rigid interdependencies between GM parameters emerge, consistent with the Strehler-Mildvan correlation (SMC). SMC emerges even when survival patterns do not conform to GM, as with cancer-prone HER2/neu mice, which die at a log-normally distributed age. Numerical experiments show that SMC includes an artifact whose magnitude depends on dataset deviation from conformance to GM irrespectively of the noisiness of small datasets, another contributor to SMC. Still another contributor to SMC is the compensation effect of mortality (CEM): a real tradeoff between the physiological factors responsible for initial vitality and the rate of its decline. To avoid misinterpretations, we advise checking experimental results against a SMC based on historical controls or on subgroups obtained by randomization of control animals. An apparent acceleration of aging associated with a decrease in the initial mortality is invalid if it is not greater than SMC suggests. This approach applied to published data suggests that the effects of calorie restriction and of drugs believed to mimic it are different. SMC and CEM relevance to human survival patterns is discussed.

Using Poisson-gamma model to evaluate the duration of recruitment process when historical trials are available

At the design of clinical trial operation, a question of a paramount interest is how long it takes to recruit a given number of patients. Modelling the recruitment dynamics is the necessary step to answer this question. Poisson-gamma model provides very convenient, flexible and realistic approach. This model allows predicting the trial duration using data collected at an interim time with very good accuracy. A natural question arises: how to evaluate the parameters of recruitment model before the trial begins? The question is harder to handle as there are no recruitment data available for this trial. However, if there exist similar completed trials, it is appealing to use data from these trials to investigate feasibility of the recruitment process. In this paper, the authors explore the recruitment data of two similar clinical trials (Intergroupe Francais du Myélome 2005 and 2009). It is shown that the natural idea of plugging the historical rates estimated from the completed trial in the same centres of the new trial for predicting recruitment is not a relevant strategy. In contrast, using the parameters of a gamma distribution of the rates estimated from the completed trial in the recruitment dynamic model of the new trial provides reasonable predictive properties with relevant confidence intervals. Copyright © 2017 John Wiley & Sons, Ltd.

Comparing oncology clinical programs by use of innovative designs and expected net present value optimization: Which adaptive approach leads to the best result?

Designing an oncology clinical program is more challenging than designing a single study. The standard approaches have been proven to be not very successful during the last decade; the failure rate of Phase 2 and Phase 3 trials in oncology remains high. Improving a development strategy by applying innovative statistical methods is one of the major objectives of a drug development process. The oncology sub-team on Adaptive Program under the Drug Information Association Adaptive Design Scientific Working Group (DIA ADSWG) evaluated hypothetical oncology programs with two competing treatments and published the work in the Therapeutic Innovation and Regulatory Science journal in January 2014. Five oncology development programs based on different Phase 2 designs, including adaptive designs and a standard two parallel arm Phase 3 design were simulated and compared in terms of the probability of clinical program success and expected net present value (eNPV). In this article, we consider eight Phase2/Phase3 development programs based on selected combinations of five Phase 2 study designs and three Phase 3 study designs. We again used the probability of program success and eNPV to compare simulated programs. For the development strategies, we considered that the eNPV showed robust improvement for each successive strategy, with the highest being for a three-arm response adaptive randomization design in Phase 2 and a group sequential design with 5 analyses in Phase 3.

Proposed best practice for projects that involve modelling and simulation

Modelling and simulation has been used in many ways when developing new treatments. To be useful and credible, it is generally agreed that modelling and simulation should be undertaken according to some kind of best practice. A number of authors have suggested elements required for best practice in modelling and simulation. Elements that have been suggested include the pre-specification of goals, assumptions, methods, and outputs. However, a project that involves modelling and simulation could be simple or complex and could be of relatively low or high importance to the project. It has been argued that the level of detail and the strictness of pre-specification should be allowed to vary, depending on the complexity and importance of the project. This best practice document does not prescribe how to develop a statistical model. Rather, it describes the elements required for the specification of a project and requires that the practitioner justify in the specification the omission of any of the elements and, in addition, justify the level of detail provided about each element. This document is an initiative of the Special Interest Group for modelling and simulation. The Special Interest Group for modelling and simulation is a body open to members of Statisticians in the Pharmaceutical Industry and the European Federation of Statisticians in the Pharmaceutical Industry. Examples of a very detailed specification and a less detailed specification are included as appendices.

The A2iA Intercheque System: Courtesy Amount and Legal Amount Recognition for French Checks

We developed a check reading system, termed INTERCHEQUE, which recognizes both the legal (LAR) and the courtesy amount (CAR) on bank checks. The version presented here is designed for the recognition of French, omni-bank, omni-scriptor, handwritten bank checks, and meets industrial requirements, such as high processing speed, robustness, and extremely low error rates.

We give an overview of our recognition system and discuss some of the pattern recognition techniques used. We also describe an installation which processes of the order of 70,000 checks per day. Results on a data base of about 170,000 checks show a recognition rate of about 75% for an error rate of the order of 1/10,000 checks.

Epitalon and colon carcinogenesis in rats: proliferative activity and apoptosis in colon tumors and mucosa

The effect of the synthetic pineal peptide Epitalon (Ala-Glu-Asp-Gly) on proliferative activity in colon tumors, and in mucosal epithelial cells adjacent to and located far from tumors was studied in rats. To evaluate the effect of Epitalon on different stages of carcinogenesis, different treatment regimens were used: during the tumor initiation stage, during the tumor-promotion stage, or during the entire process of tumor development. Eighty 2-month-old male LIO rats were exposed weekly to five subcutaneous injections of 1,2-dimethylhydrazine (DMH) at a single dose of 21 mg/kg body weight. Rats were divided into four groups. Control rats (group 1) received saline at a dose of 0.1 ml during the entire experiment. Rats in group 2 were treated with Epitalon at a dose of 1 micro g, five times a week, for 6 months, from the first injection of DMH till the end of the experiment. Rats in group 3 were treated with Epitalon after termination of the carcinogen injections. Rats in group 4 were treated with Epitalon only during the period of DMH exposure (for the first 5 weeks of the experiment). DMH induced proliferation of the secretory epithelium, and this phenomenon was accompanied by a decrease in the size of the stromal area and the area of lymph infiltration in colon tumors and in the colon mucosa adjacent to the tumors (group 1). Epitalon attenuated this effect, especially when the treatment was continued throughout the experiment (group 2). It increased the stromal areas, as well as that of lymphoid infiltration in the colon mucosa adjacent to the tumors. The intensity of lymphoid infiltration was activated in both the colon mucosa adjacent to a tumor and in the tumor. Mitotic activity of tumor cells was significantly inhibited by Epitalon when the treatment was given throughout the experiment (group 2). In parallel, a high level of apoptosis was seen in the same group. Thus, the strongest inhibitory effect of Epitalon on carcinogenesis in the colon mucosa was manifested when the treatment was continued throughout the experiment.

Gut neuroendocrine cells: relationship to the proliferative activity and apoptosis of mucous epitheliocytes in aging

OBJECTIVES

Diffuse neuroendocrine system (DNES) cells regulate homeostasis via neurocrine, endocrine and paracrine mechanisms. Extensive effects of peptide hormones and biogenic amines necessitate studying of DNES cell biology in aging. In this connection, the functional morphology of gut neuroendocrine cells (NEC), proliferative activity and apoptosis of mucous epithelial cells in aging have been studied.

MATERIAL AND METHODS

The study was performed on BALB/c-nu mice of 4, 21 and 34 months of age. NEC, proliferative activity and apoptosis of mucous epitheliocytes in stomach and duodenum have been studied by histochemical, immunohistochemical and morphometrical methods.

RESULTS

The total number of NEC shows an increasing trend with advancing age. However, the different types of NEC elicit differential patterns. The total number of epithelial cell nuclei does not show any statistically significant difference during aging. The proliferative activity of mucous epitheliocytes also shows no difference among the three animal groups studied. On the contrary, the apoptotic index increases with advancing age.

CONCLUSIONS

The results demonstrate that various gut NEC show differential behavior with age and their time-courses are dependent on the site of location (stomach or duodenum). The picture seems quite complex to allow a comprehensive interpretation, nonetheless it gives us some useful indications for further investigation. In fact, since the gut does not show evident gross age-related physiological changes, modifications with age in specific biological parameters can suggest the key mechanisms of compensative regulatory processes possibly acting during aging.

Melatonin and colon carcinogenesis. IV. Effect of melatonin on proliferative activity and expression of apoptosis-related proteins in the spleen of rats exposed to 1,2-dimethylhydrazine

The suppression of 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis by melatonin was previously demonstrated. The objective of the present work was to evaluate histologically and immunohistochemically the splenic immune response to the induced cancer and to melatonin. Spleens from rats, either untreated, injected with DMH, fed with melatonin or treated with both carcinogen and melatonin, were studied. The exposure to the carcinogen and the consequential carcinogenesis resulted in splenic changes that reflected the insufficiency of the immune response, as manifested in significant reduction of the white pulp and the simultaneous expansion of the red pulp. The effects of melatonin on most splenic components were inverse to those of DMH. The anti-carcinogenic properties of melatonin were evidenced from the reversal of the inhibitory effects of DMH, especially when the densities of lymphocytes in different parts of the spleen were compared. The combined treatment of the rats with DMH and melatonin resulted in the expansion of the splenic zones by 106% to 125%, compared to those from DMH-treated rats, and the numbers of CD8+ lymphocytes and Fas-positive cells increased sharply. Therefore we conclude that anti-carcinogenic effects of melatonin are related to activation of several elements of the host's lymphatic system.

Orbitally degenerate spin-1 model for insulating V2O3

Motivated by recent neutron, x-ray absorption, and resonant scattering experiments, we revisit the electronic structure of V2O3. We propose a model in which S = 1 V3+ ions are coupled in the vertical V-V pairs forming twofold orbitally degenerate configurations with S = 2. Ferro-orbital ordering of the V-V pairs gives a description which is consistent with all experiments in the antiferromagnetic insulating phase.

Inactivation of O6-alkylguanine-DNA alkyltransferase in the rat liver due to an intraperitoneal administration of methylated DNA

Intraperitoneal administration of 6.5 mg of in vitro methylated DNA (meDNA) containing 1.5 x 10(-4) mM of O6-methylguanine (6MG) to male outbred rats weighing 150 g led to a considerable decrease in the activity of liver O6-alkylguanine-DNA alkyltransferase (AT). One hour after treatment there occurred a 4- to 5-fold decrease in the AT activity followed by its slow recovery. However, after 48 h, AT activity considerably exceeded control levels. A 5-fold decrease in the amount of administered meDNA resulted in the absence of its effect, whereas administration of higher amounts produced a further AT inactivation. A similar treatment with non-methylated DNA did not change AT activity. The possibility of AT exhaustion under in vivo conditions and thereby inhibition of repair of O6-alkylguanine in DNA, playing a key role in mutagenic, carcinogenic and antineoplastic effects of certain alkylating agents, might be helpful in increasing susceptibility of animals to such compounds.

Persistence of carcinogenic effect in intact progeny of mice treated transplacentally with 7,12-dimethylbenz[a]anthracene

Pregnant SHR mice were treated once with 7,12-dimethylbenz[a]anthracene (DMBA) on days 17-19 of gestation. F1 and F2 descendants of these mice received multiple skin applications of 12-O-tetradecanoylphorbol-13-acetate (TPA) twice a week for 24 weeks beginning at 12 weeks of age, or applications of solvent alone. The increase in the frequency of skin tumours in F1 and F2 descendants was reported elsewhere. In addition, we report here an increase in overall numbers of tumor-bearing animals, independently of TPA treatment both in F1 and F2 groups compared to respective control groups. Separate statistical analyses were performed for lung tumours, mammary gland tumours, leukaemias and lymphomas. In both generations of descendants of DMBA-treated mothers lung tumour incidence was considerably increased and differed significantly (maximal P-value = 0.003) from control values. Local applications of TPA resulting in strong skin tumour promoting effect described in our previous paper (Napalkov et al., Carcinogenesis, 8(3) (1987) 381) did not produce any significant change in the rates of other types of tumours. The results of the present study provide additional evidence in support of the hypothesis on possibility of hereditary transmission of carcinogenic action of certain chemical compounds.

Promotion of skin tumours by TPA in the progeny of mice exposed pre-natally to DMBA

Pregnant SHR mice were treated once with 7,12-dimethylbenz[a]anthracene (DMBA) on day 17-19 of gestation, and F1 and F2 descendants received multiple skin applications of 12-O-tetradecanoylphorbol-13-acetate (TPA) twice a week for 24 weeks beginning at 12 weeks of age. Post-natal promoter treatment resulted in a high incidence of skin tumours in F1 and F2 mice (37.3 and 19.7%, respectively), whereas only 6.6% of control animals treated with TPA only developed skin tumours. DMBA was shown previously to be capable of initiating skin carcinogenesis transplacentally; however, our results on the second generation provide suggestive evidence of hereditary transmission of at least part of the initiating action of this carcinogen.

Effect of exogenous beta-glucuronidase on the carcinogenicity of 1,2-dimethylhydrazine in rats: evidence that carcinogenic intermediates form conjugates and act through their subsequent enzymatic release

Albino, outbred 3-month-old rats were given a single s.c. dose of 1,2-dimethylhydrazine dihydrochloride (DMH; 100 mg/kg) and, 6 or 24 h later, an i.v. dose of bovine liver beta-glucuronidase (3 X 10(4) Fishman units). After this treatment, the incidence of tumours of the large intestine and Zymbal gland, and of cystocholangiomas was similar to that found in rats treated with DMH alone; the incidence of malignancies in various other tissues was considerably higher than that in rats treated only with DMH, especially in animals exposed to beta-glucuronidase 24 h after administration of DMH. beta-Glucuronidase itself had no carcinogenic activity. The broadening of the spectrum of malignant tumours produced in DMH-treated rats by administration of beta-glucuronidase indicates that the carcinogenic effect of DMH may be exerted through formation of comparatively stable conjugates of its metabolites and their enzymic release in target tissues. The approach used in this study could be helpful in investigating the formation of conjugates from other carcinogens.