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Simulating strongly correlated systems with incommensurate order poses significant challenges for traditional finite-size-based approaches. Confining such a phase to a finite-size geometry can induce spurious frustration, with spin spirals in frustrated magnets being a typical example. Here, we introduce an Ansatz based on infinite projected entangled-pair states which overcomes these limitations and enables the direct search for the optimal spiral in the thermodynamic limit, with a computational cost that is independent of the spiral's wavelength. Leveraging this method, we simulate the Heisenberg model on the anisotropic triangular lattice, which interpolates between the square and isotropic triangular lattice limits. Besides accurately reproducing the magnetically ordered phases with arbitrary wavelength, the simulations reveal a quantum spin liquid phase emerging between the Néel and spin spiral phases.

We introduce a new paradigm for scaling simulations with projected entangled-pair states (PEPS) for critical strongly correlated systems, allowing for reliable extrapolations of PEPS data with relatively small bond dimensions D. The key ingredient consists of using the effective correlation length ξ for inducing a collapse of data points, f(D,χ)=f(ξ(D,χ)), for arbitrary values of D and the environment bond dimension χ. As such we circumvent the need for extrapolations in χ and can use many distinct data points for a fixed value of D. Here, we need that the PEPSs have been optimized using a fixed-χ gradient method, which can be achieved using a novel tensor-network algorithm for finding fixed points of 2D transfer matrices, or by using the formalism of backwards differentiation. We test our hypothesis on the critical 3D dimer model, the 3D classical Ising model, and the 2D quantum Heisenberg model.

Doubts have been raised on the representation of chiral spin liquids exhibiting topological order in terms of projected entangled pair states (PEPSs). Here, starting from a simple spin-1/2 chiral frustrated Heisenberg model, we show that a faithful representation of the chiral spin liquid phase is in fact possible in terms of a generic PEPS upon variational optimization. We find a perfectly chiral gapless edge mode and a rapid decay of correlation functions at short distances consistent with a bulk gap, concomitant with a gossamer long-range tail originating from a PEPS bulk-edge correspondence. For increasing bond dimension, (i) the rapid decrease of spurious features-SU(2) symmetry breaking and long-range tails in correlations-together with (ii) a faster convergence of the ground state energy as compared to state-of-the-art cylinder matrix-product state simulations involving far more variational parameters, prove the fundamental relevance of the PEPS ansatz for simulating systems with chiral topological order.

Possible causal relationship between development of atherosclerosis and Chlamydia pneumoniae infection is discussed. If the hypothesis is verified, antibiotics will play important role in the treatment of this artery disease.

An effect of a 14-day drinking of coffee on some blood serum indices of lipid metabolism was investigated in 20 healthy volunteers and 20 patients with hyper lipoproteinemia (type IIb). The study was carried out in two subgroups: healthy volunteers or patients with hyperlipoproteinemia assigned to the first subgroup drank ordinary coffee and patients assigned to the second subgroup drank coffee deprived of irritant substances (4 glasses daily). It was found that ordinary coffee significantly increased total serum cholesterol and decreased serum HDL-cholesterol in healthy volunteers. Such effects were not seen in subgroup drinking coffee deprived of irritant substances. More significant increase in serum total cholesterol and decrease in serum HDL-cholesterol were found in patients with hyperlipoproteinemia. Drinking of modified coffee does not cause any significant changes in serum lipid metabolism. The authors concluded that drinking of the ordinary coffee should be restricted in patients with hyperlipoproteinemia and use of coffee deprived of irritant substances might be recommended to patients with this disease.

Effect of 14 days coffee drinking upon some blood serum indices of lipid metabolism was studied on 20 healthy volunteers and 20 patients with hyperlipoproteinemia (type IIb). The study was done in two subgroups: healthy volunteers or patients with hyperlipoproteinemia which had belonged to the first subgroup drank ordinary coffee and the ones which belonged to the second subgroup drank coffee deprived of irritant substances. (4 glasses per day). It was found that in healthy volunteers ordinary coffee had given rise to a significant increase of serum total cholesterol and to a decrease of serum HDL-cholesterol. These changes were not observed in subgroup drinking coffee deprived of irritant substances. More significant rise of serum total cholesterol and decrease of serum HDL-cholesterol were found in patients with hyperlipoproteinemia. Drinking of modified coffee does not cause any significant changes in serum indices of lipid metabolism. The authors concluded that drinking of ordinary coffee should be restricted in patients with hyperlipoproteinemia and coffee deprived of irritant substances might be recommended to patients with this disease.

Gastric cancerogenesis is a multistage process. Dietary studies may contribute to elucidation of that complex problem.

Our first stage 3-week trial (6) and second stage up to 6 weeks (7) showed that ranitidine provides the highest healing rate of 97% for duodenal and 95% for gastric ulcer. The study has been now prolonged for one year to assess the efficacy of maintenance therapy. Out of 258 patients who completed the second stage 232 voluntarily entered the open stage 3 in which they were given a single dose R 150 mg nocte, and were endoscopied after 4, 8 and 12 months. There were 153 duodenal and 79 gastric ulcers. 191 patients completed the study; no undesired effects were found and there was no medical reason to withdraw the drug from the long term use. Recurrent ulcer was found in 33.3% out of 126 duodenal ulcer cases, and in 29.2% out of 65 gastric ulcer patients who completed stage three. Sixteen percent of recurrent gastric ulcers and 26% of duodenal ulcers were asymptomatic. Recurrence rate was about twice as high in smokers as in non-smokers. These findings were compared with our long-term endoscopic survey of the natural history of peptic ulcer disease (8) in which yearly recurrence rate of duodenal ulcer was 68.4% and of gastric ulcers 73.5%, 14% of them being painless. This indicates that R is fairly well tolerated in long term use and may be useful to curb the ulcer recurrence rate.

The aspiration biopsy with thin-needles controlled by computer tomography permits an aimed, safety and nearly not dangerous investigation of patients with liver and pancreas diseases. The cytologic examination allows the differentiation of neoplastic tumors from other processes.

After a time of overstated diet prescriptions nowadays the individual nutrition of the patient with ulcer with a diet of high quality is striven for. Such a diet must guarantee the intake of an adequate quantity of calories, with regard to the main nutrient media protein, fats and carbohydrates it must be well composed and must meet the requirements of minerals, vitamins and fluid. The diet shall be varied, and more frequent smaller meals are to be recommended.

Compared with the intravenous cholangiography the infusion cholangiography is the more effective and unambiguous investigation method of the gallbladder and the bile ducts. It considerably enlarges the diagnostic possibilities in the area of the bile ducts. A serum bilirubin level of more than 2 mg/100 ml allows positive cholangiograms by means of the infusion method, but is nearly always the cause for negative findings in intravenous application. In a hypalbuminaemia lower than 3 g/100 ml, in an increase of the alkaline serum phosphatase, of the serum transaminase and a pathological retention of bromsulphalein the bile ducts cannot be demonstrated also in the infusion cholangiography. A 20% glucose solution is sufficient as solvent in the infusion cholangiography. In the negative case the cholecystography and the intravenous cholangiography may be supplemented and enlarged by application of the infusion cholangiography as a more evident method of X-ray examination.

The purpose of present investigations was to evaluate the effect of peptide diet upon clinical and metabolic course of chronic pancreatitis. Nitrogen, potassium and sodium balances were done for 24 days in 4 patients with chronic pancreatitis fed with peptide diet as well as in 5 patients fed with normal low fat diet. Administration of peptide diet improved protein nutritional status of all patients, due to better absorption of aminoacid components and increased nitrogen retention. On the basis of obtained results the authors discuss possibility of dietary treatment of chronic pancreatitis with peptide diet.

In 26 patients with the classical clinical picture of an ulcerous colitis and in 8 healthy control persons in the course of a rectoscopy in about 15 cm depth tissue was taken bioptically and underwent an electron-microscopic investigation. Moreover, enzyme-histological examinations were performed. Summarizingly, clear references to immune-pathological processes for development and course of ulcerous colitis are the result.

The study was carried out in 168 patients treated in 5 Departments of Gastroenterology according to a standardized design. All were diagnosed and followed-up by panendoscopy: they were give similar diet and antacids ad libitum, and were urged not to smoke. Such basic therapy in our studies resulted in 30-40% of gastric, and about 50% of duodenal ulcers coded packages of the tested drug. Tablets contained wither 150 mg of Ranitidine or placebo They were taken twice a day. Spontaneous healing under such conditions occurred in the present study in 37% of gastric, and 45% of duodenal, ulcers, while in patients taking Ranitidine 62% of gastric (P less than 0.05) and 82% of duodenal ulcers (p less than 0.01) were cicatrized after 3 weeks. There were no drop-outs, and no undesired effects were observed.