bluuebunny/crossref_metadata_2025 huggingface dataset:
Brazilian universities and graduate programmes in Geography: Institutional developments and political challenges
Authors: Reyes Novaes André , Araújo Lamego Mariana
Published: October 2021

This piece examines the spread of Geography graduate programmes in Brazil, demonstrating how political contexts affect geographical research and teaching. Four periods are identified, considering changes in Brazilian politics and our own experience as students and professors at public universities. The creation of the first Geography graduate programmes during the dictatorship in the 1970s, the introduction of neoliberal policies during the 1990s, the expansion of Brazilian universities during the 2000s, and the contemporary challenges and threats to public universities characterised different periods that influenced the practices of making Geography in Brazil. Considering the territorial diffusion and the social composition of graduate programmes in Geography during different periods, we would like to emphasise the importance of an accessible, public, and inclusive university in the Global South.
Requests in Indian and Sri Lankan English
Authors: Degenhardt Julia
Published: October 2021

Despite notable exceptions, research on requests in world Englishes has so far largely involved role plays, questionnaires and discourse completion tasks. Moreover, research on requests in South Asian varieties of English is rather scarce. Therefore, the present study employs a multifactorial approach towards requests in Indian and Sri Lankan English as compared to their historical input variety British English by investigating the spoken components of the International Corpus of English, hence involving authentic, non‐intuition‐based empirical data. Based on a conditional inference tree and a random forest extended via the integration of interaction predictors, the present article concludes that quantitative differences in the realisation patterns of requests in British, Indian and Sri Lankan English can be observed.
The Newtonian gravity of irregular shapes using STL files and 3D printing
Authors: Rossi Eduardo
Published: October 2021

The gravitational interactions of irregular shapes are rarely discussed in the compulsory schooling system and sometimes even ignored at the university level. This omission is due to the complexities encountered in extending Newton's law of gravitation to bodies that are not spherical. However, a deep understanding of the link between the gravity and the shape is quite important to interpret some basic facts of nature. In this paper, we show how simple concepts can be used to create a more general algorithm that has been implemented in matlab to compute the gravity of irregular bodies. Shapes are described in terms of Standard Tessellation Language files, the standard format for 3D printing. This approach to teaching allows students to model physical bodies, and the 3D representation of complex problems can help students acquire a more complete understanding of physics.
Socioeconomic and Gender Inequalities in Leisure-Time Physical Activity and Access to Public Policies in Brazil From 2013 to 2019
Authors: Wendt Andrea , Ricardo Luiza I.C. , Costa Caroline S. , Knuth Alan G. , Tenório Maria C.M. , Crochemore-Silva Inácio
Published: October 2021

Background: This study aims to describe changes in gender and wealth inequalities in leisure-time physical activity (PA) of Brazilians during a 6-year interval. It also aims to evaluate inequalities regarding PA public programs awareness, participation, and access to public spaces for PA. Methods: Data from 2 population-based surveys conducted in 2013 and 2019 were used. Leisure-time PA prevalence was assessed considering those reporting ≥150 minutes per week. The authors evaluated gender inequalities calculating differences and ratios, and wealth inequalities using the slope index of inequality and the concentration index— assessing changes over time. Results: National levels of leisure-time PA increased from 2013 to 2019, and an increase in inequalities was observed; women and the poorest groups still presented lower prevalence. A decline in socioeconomic inequalities was observed from 2013 to 2019 regarding the availability of public spaces and awareness about public programs. However, outcomes remained more common among the richest group. Inequalities did not vary for participation in public programs. Conclusion: Although leisure-time PA increased from 2013 to 2019 at a national level, there were no improvements in gender inequalities, and wealth inequalities worsened over time. Indicators of public strategies for PA increased for the population, but inequalities remain.
Correction
Authors: Bern Howard A.
Published: October 2021

The article "Antifolliculoid Activity of Vitamin A" (Kahn, Raymond H. and Bern, Howard A.,
Science
, 1950, 111, 516) contains an error. The words ". . . and inactivate," at the end of the first line, paragraph 2, p. 516, should be deleted.
Tetragonal Iron Sulfide
Authors: Berner Robert A.
Published: October 2021

Studies of synthetic iron sulfides formed from aqueous solution at 25°C and atmospheric pressure have revealed the existence of a new phase, tetragonal FeS. This phase is formed as the initial corrosion product of metallic iron or steel in solutions of hydrogen sulfide. It has been discovered as an iron corrosion product in the sediments of the Mystic River at Boston, Massachusetts.
Intercellular Connection between Smooth Muscle Cells: the Nexus
Authors: Dewey Maynard M. , Barr Lloyd
Published: October 2021

High-resolution electron microscopy has revealed that the regions of contact between smooth muscle cells from dog intestine are areas of fusion of adjacent cell membranes. For morphological and functional reasons this type of contact between excitable cells has been termed a nexus.
α-D-Glucose: Precise Determination of Crystal and Molecular Structure by Neutron-Diffraction Analysis
Authors: Brown George M. , Levy Henri A.
Published: October 2021

This analysis provides the first precise crystal and molecular structural parameters for α-D-glucose. The C—C, C—H, and O—H bond lengths deviate only slightly from their means of 1.523 Å, 1.098 Å, and 0.968 Å. The C(1)—O(1) bond length, 1.389 Å, is significantly shorter than the mean value, 1.420 Å, of the other C—O bonds. The valence angle of the ring oxygen is 113.8 degrees.
Cestode in North Dakota:
Echinococcus
in Field Mice
Authors: Leiby Paul D.
Published: October 2021

Field mice (
Microtus pennsylvanicus
and
Peromyscus maniculatus
) are naturally infected with
Echinococcus multilocularis
. Thus, the sylvatic cycle (fox to field mice to fox) has been established in North Dakota. This cestode is expected to extend its range to other agricultural regions of the continental United States where similar conditions favorable for the completion of its life cycle exist.
Antibodies in Gastric Juice
Authors: Fisher June Marion , Rees Carolyn , Taylor Keith B.
Published: October 2021

The presence in gastric juice of specific antibody has been demonstrated. It is mainly an IgG antibody reacting with the cytoplasm of gastric cells; it has been detected in patients with atrophic gastritis, with or without pernicious anemia, whose serums contain antibodies to parietal-cell cytoplasm. Evidence is presented that associated circulating antibody to cytoplasm of thyroid acinar cell does not appear in the gastric juice.
Relative Turgidity of Leaves: Temperature Effects in Measurement
Authors: Millar B. D.
Published: October 2021

The technique generally used for measuring relative turgidity may lead to large errors. This error arises when there is a difference between the in situ leaf temperature and the arbitrary constant temperature used in the determination of uptake. Similar errors may occur in methods for measuring leaf water potential.
Anticholinergic Blockade of Centrally Induced Thirst
Authors: Levitt Robert A. , Fisher Alan E.
Published: October 2021

A cholinergic antagonist applied to many of the limbic and diencephalic structures, cholinergic stimulation of which induces thirst, prevents drinking in response to cholinergic stimulation of other parts of the system. Thus, the elicitation of drinking after chemical stimulation of a particular site seems to be dependent on the functional state of other structures in the circuit.
Milk and Lactose Intolerance in Healthy Orientals
Authors: Huang Shi-Shung , Bayless Theodore M.
Published: October 2021

Nineteen of 20 healthy Oriental adults living in the United States developed abdominal cramps and diarrhea after ingesting an amount of lactose equivalent to that in one quart of milk; 14 reported similar symptoms after one or two glasses of milk; all had consumed milk as infants without having such symptoms. Two of 20 Caucasians tested were intolerant to milk and lactose. Many Orientals therefore may have a genetically determined lactase deficiency that may lead to intolerance to milk. Since lactase deficiency is also common among Negroes, the bulk of the world's adult population is probably intolerant to milk.
Thermally Driven Rossby-Mode Dynamo for Solar Magnetic-Field Reversals
Authors: Gilman Peter A.
Published: October 2021

There is increasing interest in the possible existence of large eddies or "Rossby waves" in Sun's convection zone and photosphere. It is shown that many flows of this type, driven by an equator-pole temperature difference, act as hydromagnetic dynamos to produce magnetic fields that periodically reverse. The periods and field amplitudes agree with solar phenomena within an order of magnitude.
Amoebic Meningoencephalitis: Axenic Culture of
Naegleria
Authors: Červa L.
Published: October 2021

A medium consisting of 2 percent Bacto-Casitone (Difco) and 10 percent fresh horse serum in distilled water ensures axenic growth of two pathogenic isolates of
Naegleria
species.
General method for iron-catalyzed multicomponent radical cascades–cross-couplings
Authors: Liu Lei , Aguilera Maria Camila , Lee Wes , Youshaw Cassandra R. , Neidig Michael L. , Gutierrez Osvaldo
Published: October 2021

Iron links a trio

Iron holds particular appeal as a catalytic metal—it is safe and abundant, as well as a mainstay of enzymatic reactivity. Nonetheless, in synthetic construction of carbon-carbon bonds, modern chemists have largely had to rely on rarer metals such as palladium. Liu
et al
. now report that coordination of iron by a bulky chelating phosphine ligand enables efficient mutual coupling of three different reactants—an alkyl halide, an aryl Grignard, and an olefin—to form two carbon-carbon bonds (see the Perspective by Lefèvre). A combination of Mössbauer spectroscopy, crystallography, and computational simulations illuminates the mechanism. —JSY
Integrase Inhibitor Resistance Mechanisms and Structural Characteristics in Antiretroviral Therapy-Experienced, Integrase Inhibitor-Naive Adults with HIV-1 Infection Treated with Dolutegravir plus Two Nucleoside Reverse Transcriptase Inhibitors in the DAWNING Study
Authors: Underwood Mark , Horton Joe , Nangle Keith , Hopking Judy , Smith Kimberly , Aboud Michael , Wynne Brian , Sievers Jörg , Stewart Eugene L. , Wang Ruolan
Published: October 2021

At week 48 in the phase IIIb DAWNING study, the integrase strand transfer inhibitor (INSTI) dolutegravir plus 2 nucleoside reverse transcriptase inhibitors demonstrated superiority to ritonavir-boosted lopinavir in achieving virologic suppression in adults with HIV-1 who failed first-line therapy. Here, we report emergent HIV-1 drug resistance and mechanistic underpinnings among dolutegravir-treated adults in DAWNING.
Synergy Mechanisms of Daptomycin-Fosfomycin Combinations in Daptomycin-Susceptible and -Resistant Methicillin-Resistant Staphylococcus aureus:
In Vitro
,
Ex Vivo
, and
In Vivo
Metrics
Authors: Mishra Nagendra N. , Lew Cassandra , Abdelhady Wessam , Lapitan Christian K. , Proctor Richard A. , Rose Warren E. , Bayer Arnold S.
Published: October 2021

Increased usage of daptomycin (DAP) for methicillin-resistant
Staphylococcus aureus
(MRSA) infections has led to emergence of DAP-resistant (DAP-R) strains, resulting in treatment failures.
Plasmodium falciparum Cysteine-Rich Protective Antigen (CyRPA) Elicits Detectable Levels of Invasion-Inhibitory Antibodies during Natural Infection in Humans
Authors: Mian Syed Yusuf , Somanathan Anjali , Chaddha Kritika , Pandey Alok K. , Singh Hina , Krishna Sri , Chaturvedi Neha , Uchoi Seemalata , Shukla Man Mohan , Bharti Praveen K. , Singh Neeru , Chauhan Virander Singh , Gaur Deepak
Published: October 2021

Plasmodium falciparum
cysteine-rich protective antigen (CyRPA) is a conserved component of an essential erythrocyte invasion complex (RH5/Ripr/CyRPA) and a target of potent cross-strain parasite-neutralizing antibodies. While naturally acquired human RH5 antibodies have been functionally characterized, there are no similar reports on CyRPA.
Women with kidney disease can be given a personal risk assessment for pregnancy
Authors: Saul Helen , Gursul Deniz
Published: October 2021

The study

Wiles K, Webster P, Seed PT, et al. The impact of chronic kidney disease Stages 3-5 on pregnancy outcomes.
Nephrol Dial Transplant
2020;gfaa247.

To read the full NIHR Alert go to:
https://evidence.nihr.ac.uk/alert/women-kidney-disease-given-risk-assessment-pregnancy/
Telemedicine as an alternative way to access abortion in Italy and characteristics of requests during the COVID-19 pandemic
Authors: Brandell Karin , Vanbenschoten Hannah , Parachini Mirella , Gomperts Rebecca , Gemzell-Danielsson Kristina
Published: October 2021

Introduction

Induced abortion is legal in Italy but with restrictions. The online abortion provider Women on Web (WoW) serves as an alternative way to access abortion. The COVID-19 pandemic has affected sexual and reproductive health worldwide. Italy was one of the first countries hit by the pandemic and imposed strict lockdown measures. We aimed to understand why women requested WoW abortion in Italy and how this was affected by the pandemic.

Methods

We conducted an observational study analysing requests made to WoW before and during the pandemic. We analysed 778 requests for medical abortion from Italy between 1 March 2019 to 30 November 2020 and compared the characteristics of requests submitted before and during the pandemic. We also performed subgroup analysis on teenagers and COVID-19-specific requests.

Results

There was an increase in requests during the COVID-19 pandemic compared with the previous year (12% in the first 9 months). The most common reasons for requesting a telemedicine abortion through WoW were privacy-related (40.9%); however, this shifted to COVID-19-specific (50.3%) reasons during the pandemic. Requests from teenagers (n=61) were more frequently made at later gestational stages (p=0.003), had a higher prevalence of rape (p=0.003) as the cause of unwanted pregnancies, and exhibited less access to healthcare services compared with adult women.

Conclusions

There was an increase in total demand for self-managed abortion during the pandemic and reasons for requesting an abortion changed, shifting from privacy-related to COVID-19-specific reasons. This study also highlighted the uniquely vulnerable situation of teenagers with unwanted pregnancies seeking self-managed abortion.
Accumulation of Strontium-90 in Human Teeth as a Result of Nuclear Fall-Out
Authors: Starkey Will
Published: October 2021

Strontium-90, resulting from nuclear fall-out, is taken up by bone and tooth during periods of calcification. The results are reported of a dental survey carried out by the Royal Navy since 1959. There is a time lag of three to four years between the development of the roots and the development of the crowns in relation to the total period of calcification which allows the probable rate of uptake to be determined from tooth assays. Since there is close correlation between tooth and bone levels, tooth assays may be used to monitor bone levels in living subjects.
A Survey of Recent Motion Sickness Research
Authors: Brand J. J.
Published: October 2021

The only drugs which appear to give consistently reliable protection against symptoms are hyoscine, diphenhydramine, cyclizine and promethazine. Field trials have indicated dose levels of hyoscine and cyclizine which can be expected to afford good protection with a minimum of side effects. Human and animal studies are described which have helped to clarify the mechanism and site of action of motion sickness drugs. Experiments carried out in life-rafts at sea indicate that nausea and vomiting can be controlled by a dose of 0.2 milligrams of hyoscine hydrobromide given intramuscularly.
Solitary Lesions of the Liver Displayed by Radioisotope Scanning
Authors: Ackery D. Melville
Published: October 2021

A short presentation to illustrate the value and simplicity of liver scanning in cases of hepatomegaly. Since scanning may be the investigation essential to precise diagnosis, it should be carried out at an early stage.
A History of Mass Radiography of the Chest in the Royal Naval Barracks, Portsmouth
Authors: Price Sydney H. R.
Published: October 2021

Mass Radiography of the chest was introduced by the Royal Naval Medical Service. The first two departments were opened in Chatham and Portsmouth in 1940. In spite of the large numbers of immigrants arriving in this country, the civilian authorities have announced their intention to phase out their mobile units. A brief summary of results obtained in the Portsmouth Naval Department for the periods 1940-1943 and 1966-1969 is included.
The Challenge of Underwater Exploration
Authors: Barnard E. E. P.
Published: October 2021

Diving is limited to a narrow range of depth and a limited radius of action, whereas submarines, submersible craft and bathyscaphes give men either a wider range of activity or, at depths where divers cannot operate, protection from the physical and physiological hazards which would otherwise prevent exploration of the deep oceans. The various factors which limit or inhibit the penetration of divers to the greatest depths arise from being air-breathing mammals adapted to living at atmospheric pressure. Each new solution brings new problems, but voice distortion and excessive loss of body heat are current problems nearing solution.

The analysis of present trends is presented in the context of the author’s definition of diving as ‘the use of engineering and physiological knowledge to carry out underwater tasks’.
The Use of Scinti-Scanning in the Diagnosis of Pulmonary Embolism
Authors: Macleod Murdoch A.
Published: October 2021

It is becoming increasingly evident that in many patients with pulmonary embolism, diagnosis is made difficult by minimal or absent symptoms and normal appearance of the chest X-ray, especially in the earlier stages. In this paper 30 cases of suspected pulmonary embolism are presented, 23 of whom were radiologically normal and whose symptoms ranged from that of severe to minor. It is concluded that lung scanning is a highly sensitive indicator for, and the investigation of first choice in, the diagnosis of pulmonary embolism.
Naval Medical Ceramics
Authors: Pugh P. D. Gordon
Published: October 2021

Only comparatively recently has interest been taken in medical ceramics. Because of this examples are few and far between. Some naval pharmacy jars, leech jars and infusion jugs have survived and are described.
Hypersensitivity Reaction to Lignocaine
Authors: Walker R. T.
Published: October 2021

A case is described of a hypersensitivity reaction resulting from the administration of a dental local anaesthetic.
Patellectomy for Chondromalacia Patellae
Authors: Chakraverty A. C.
Published: October 2021

Chondromalacia patellae presents a challenge to the orthopaedic surgeon, especially in the Royal Navy, where this condition is found to be very common. The disability from this condition often outweighs the usefulness of the patella as a bone and, not infrequently, a surgeon has to resort to an ablative procedure like patellectomy when other methods of treatment have failed. The overall results of pateilectomy are good, but they often tend to be disappointing in the adolescent, eg, the Royal Marine recruit, which explains the surgeon’s hesitation in performing total excision of the patella in this young group of patients. The causes of the failures have been discussed. The initial results of patelloplasty have been promising.
The Physiology of Cold/Wet Survival
Authors: Hervey G. R.
Published: October 2021

The physiology and effectiveness of the body’s thermoregulatory mechanisms are studied. The working of the control system is discussed and its effects demonstrated. The general effect of this thermoregulation on the likelihood of survival is considered, together with the principles of treatment for those suffering from immersion or exposure.
Non-Narcotic Analgesics — Their use and Abuse
Authors: Cliff J. M.
Published: October 2021

There is now available a considerable range of non-narcotic analgesics; many are still supplied in the form of compound tablets although true synergy is rare in clinical pharmacology. The value of these analgesics is discussed and their many other uses outlined. Drug toxicity and drug interaction constitute an important part of modern clinical therapeutics and the rapidly expanding literature is reviewed in an attempt to both clarify and summarise the present position.
Inhalation of the Crown of a Tooth by a Conscious Patient
Authors: Radford R. , Rudge G. H. A. , Scanlan S. G. , Smith A. F. J.
Published: October 2021

This communication is presented to: (a) Stress that inhalation of a foreign body can occur whilst the patient is conscious. (b) To illustrate the problems of anaesthetising a bronchoscopy patient.
Obesity in Childhood
Authors: Bennett A. N.
Published: October 2021

Obesity is the most important nutritional disease in the developed countries of the world. Since there is no internationally agreed criterion for diagnosis, either for adults or children, an exact figure for prevalence cannot be quoted but surveys suggest that, in highly developed countries, about one third of the population is overweight to an extent associated with d’minished life expectancy. (Office of Health Economics, 1969.)
Fibreoptic Endoscopy of the Upper Gastrointestinal Tract and its Application in the Royal Navy
Authors: Hunt Richard H.
Published: October 2021

Fibreoptic endoscopy of the gastrointestinal tract is now a well established technique and an invaluable diagnostic tool in the dyspeptic patient. In this paper the experience of 137 examinations carried out over a six month period at the Royal Naval Hospital Haslar is presented together with a discussion of the implications of this examination in the Royal Navy.
A Case of Grossly Infected Fracture of the Mandible
Authors: Hall T. J. C.
Published: October 2021

In Naval dental practice the great majority of the patients who have received a fractured jaw attend for treatment shortly after injury. A case is presented here of a patient who acquired a compound and displaced fracture of the mandible some two or three weeks before seeking assistance, by which time gross infection was established.
Delayed Wound Closure
Authors: Watt James
Published: October 2021

Although first practised by a naval surgeon during the Crimean War, the principles of delayed wound closure have had to be relearned in every subsequent conflict. Recent studies of missile ballistics have revealed their potential for extensive tissue injury and widespread contamination beyond the limits of the missile track. Radical wound debridement with delayed wound closure at the optimal time are mandatory.
47Ca and 85Sr Absorption and Excretion Compared in Normal Controls
Authors: Macleod Murdoch A.
Published: October 2021

The absorption and excretion of 47Ca and 85Sr, measured by an arm counting technique is compared, and the effect of increasing carrier loads of stable calcium demonstrated. The net absorption of 47Ca was found to be greater than that of 85Sr, at all levels of calcium intake although the net absorption of both isotopes fell as the calcium carrier loud was increased.

The excretion of 85Sr, measured by arm counting, was 3.36 times greater than that of 47Ca. This compares favourably with figures of 3.34 (Nordin, Smith and Nisbet 1964) and 3.5 (Barnes, Bishop, Harrison and Sutton, 1961) derived from plasma, urinary and faecal measurements made over a period of seven days in a hospital metabolic unit.
Trans-rectal Prolapse of Ileum from the Anus
Authors: Taylor E. W.
Published: October 2021

A case of prolapse of ileum from the anus after spontaneous rupture of the rectum is presented. This, like some others suffering this rare event, followed a fall which presumably raised the intra-abdominal pressure. The aetiological factors and management of the case are discussed.
Globus Hystericus and Cervical Osteophytes
Authors: Counter R. T.
Published: October 2021

Globus hystericus is an unfortunate name. As with most functional diagnoses it has become a medical dustbin. This paper attempts to show that with increasing knowledge the diagnosis becomes rarer. An emphasis is placed upon cervical osteophytes as a not uncommon cause.
A Comparison of Two Quantitative Methods of Analysing Thyroid Dynamic Studies in Nuclear Medicine
Authors: Houston A. S. , Thorpe N. R.
Published: October 2021

Two quantitative methods of analysing thyroid dynamic studies using 99mTc O-4 are compared for 33 patients (22 euthyroid, 8 hyperthyroid and 3 hypothyroid). A physiological model based on pertechnetate uptake by the thyroid is compared with principal components analysis. Both methods gave good separation between euthyroid and hvperthyroid in all but one case, while the separation between euthyroid and hypothyroid, although based on a small sample, appeared to be better for principal components analysis.
Anatomy of the lumbar interspinous ligament: findings relevant to epidural insertion using loss of resistance
Authors: Lawrence Sue , Llewellyn Stacey , Hunt Helen , Cowin Gary , Sturgess David J , Reutens David
Published: October 2021

Background and objectives

The ‘loss of resistance’ technique is used to determine entry into the epidural space, often by a midline needle in the interspinous ligament before the ligamentum flavum. Anatomical explanations for loss of resistance without entry into the epidural space are lacking. This investigation aimed to improve morphometric characterization of the lumbar interspinous ligament by observation and measurement at dissection and from MRI.

Methods

Measurements were made on 14 embalmed donor lumbar spines (T12 to S1) imaged with MRI and then dissected along a tilted axial plane aligned with the lumbar interspace.

Results

In 73 interspaces, median (IQR) lumbar interspinous plus supraspinous ligament length was 29.7 mm (25.5–33.4). Posterior width was 9.2 mm (7.7, 11.9), with narrowing in the middle (4.5 mm (3.0, 6.8)) and an anterior width of 7.3 mm (5.7, 9.8).

Fat-filled gaps were present within 55 (75%). Of 51 anterior gaps, 49 (67%) were related to the ligamenta flava junction. Median (IQR) gap length and width were 3.5 mm (2.5, 5.1) and 1.1 mm (0.9, 1.7).

Detection of gaps with MRI had 100% sensitivity (95% CI 93.5 to 100), 94.4% specificity (72.7, 99.9), 98.2% (90.4, 100) positive predictive value and 100% (80.5, 100) negative predictive value against dissection as the gold standard.

Conclusions

The lumbar interspinous ligament plus supraspinous ligament are biconcave axially. It commonly has fat-filled gaps, particularly anteriorly. These anatomical features may form the anatomical basis for false or equivocal loss of resistance.
Aggregate stability after 25 years of organic, conventional, and grassland management
Authors: Stainsby April , Entz Martin H.
Published: October 2021

Aggregate stability (AS) was measured in the 25th year of a long-term organic — conventional comparison field study. Located in southern Manitoba, the study includes two, four-year crop rotations under conventional and organic management, plus a grassland. The forage-grain rotation includes alfalfa (Medicago sativa)–alfalfa–wheat (Triticum aestivum)–flax (Linum usitatissimum). The grain only rotation includes wheat–flax–oat (Avena sativa)–soybean (Glycine max); hairy vetch (Vicia villosa) is substituted for soybean in the organic system. Composted manure was added every 4 yr to half of the organic forage-grain rotation to correct a phosphorus deficiency. The wheat and flax phases were sampled at depths (0–10 cm; 10–20 cm) in spring 2017, and wet aggregate stability was measured using the Yoder method with stacked sieves. Mean weight diameter (MWD) was calculated. AS in the organic systems was never lower than that of comparable conventional systems, but had more large aggregates in only a few cases. Our hypothesis that including alfalfa would increase AS was supported in only a few instances. The largest aggregates (1–2 mm and 2–6.3 mm) and the fewest smallest aggregates (0.25–0.5 mm) were observed in the grassland. For the intermediate aggregate size class (0.5–1 mm), the organic forage-grain systems had levels similar (P > 0.05) to the grassland. While adding manure increased plant growth by about 40% in the organic forage-grain rotation, no AS differences were observed. Limited AS response in the arable systems may be due to suboptimal soil C contents; only the grassland had a C content above the minimum 35 g·kg−1 postulated for Vertisols.
EFFICIENT INCREMENTAL SIMULATION OF “1/f” NOISES
Authors: VOSS RICHARD F.
Published: October 2021

Large-scale simulations and analysis of the original powers of 2 geometric source sum algorithm for simulating [Formula: see text] noise confirm that it provides a reasonably accurate approximation to an exact [Formula: see text] spectral density with a Gaussian amplitude distribution over any arbitrarily large frequency range. This incremental algorithm is computationally efficient with a computation time, after initialization, that varies linearly with the number of samples generated. A new variation allows non-integer and random ratios for the geometric sequence that reduces variations about the exact power-law spectral density and, by varying individual source amplitudes, produces generalized [Formula: see text] noises.
Scalar positive immersions
Authors: Florit Luis A. , Hanke Bernhard
Published: October 2021

As shown by Gromov–Lawson and Stolz the only obstruction to the existence of positive scalar curvature metrics on closed simply connected manifolds in dimensions at least five appears on spin manifolds and is given by the non-vanishing of the [Formula: see text]-genus of Hitchin. When unobstructed we shall realize a positive scalar curvature metric by an immersion into Euclidean space whose dimension is uniformly close to the classical Whitney upper bound for smooth immersions. Our main tool is an extrinsic counterpart of the well-known Gromov–Lawson surgery procedure for constructing positive scalar curvature metrics.
Power concavity for elliptic and parabolic boundary value problems on rotationally symmetric domains
Authors: Ishige Kazuhiro , Salani Paolo , Takatsu Asuka
Published: October 2021

We study power concavity of rotationally symmetric solutions to elliptic and parabolic boundary value problems on rotationally symmetric domains in Riemannian manifolds. As applications of our results to the hyperbolic space [Formula: see text], we have

The first (positive) Dirichlet eigenfunction of the Laplacian on a ball in [Formula: see text] raised to some power [Formula: see text] is strictly concave; Let [Formula: see text] be the heat kernel on [Formula: see text]. Then [Formula: see text] is strictly log-concave in [Formula: see text] for [Formula: see text] and [Formula: see text].
A New Estimation of Failure Analysis in Fuzzy Environment, Case Study: The Electrical Model Failure for the Football Stadium
Authors: Allahviranloo T. , Abbasi F.
Published: October 2021

In this paper, we propose the new fuzzy arithmetic operations based on transmission average on pseudo-hexagonal fuzzy numbers from [F. Abbasi, T. Allahviranloo and S. Abbasbandy, A new attitude coupled with fuzzy thinking to fuzzy rings and fields, Journal of Intelligent and Fuzzy Systems 29 (2015) 851–861]. The properties of these propose operations and their fundamental qualities are discussed in detail. Several illustrative examples were given to show the accomplishment and ability of the proposed method. Finally, as a applied rudimentary case study an electric network model of a football stadium is considered in fuzzy environment. The reliability of components for the proposed model is considered as pseudo-hexagonal fuzzy number.
A Recommendation Model for College Career Entrepreneurship Projects Based on Deep Learning
Authors: Feng Yuan , Huang Weixian
Published: October 2021

The recommendation system is an active, personalized, and real‐time technology platform proposed in the 1990s to solve the problem of information overload. The recommendation system can constantly adjust the recommendation results according to the real‐time behaviors of users. In other words, if the user’s interest changes, the recommendation system can present different information to the user. Therefore, the recommendation system is the best way to solve the problem of information overload in entrepreneurial projects. Based on the ConvMF algorithm, this paper proposes an entrepreneurial project recommendation algorithm based on a deep neural network and matrix decomposition. A deep neural network was established for the extraction of the hidden features of entrepreneurial projects, and a convolution neural network was used to process the text description information of entrepreneurial projects. One‐hot coding was used to process the regional characteristics and financing round characteristics of entrepreneurial projects, and word embedding was used to process the label features of entrepreneurial projects. The implicit features of users are extracted from the user’s rating matrix using matrix decomposition technology. Finally, recommendations are made according to the implicit characteristics of users and the items learned.
Nonfragile Synchronization of Semi-Markovian Jumping Neural Networks with Time Delays via Sampled-Data Control and Application to Chaotic Systems
Authors: Sivaranjani K. , Sivakumar M. , Dharani S. , Loganathan K. , Ngmgyel Ngawang
Published: October 2021

This study discusses the synchronization problem for delayed neural networks with semi-Markovian jumping parameters. With the support of Jenson’s inequality and Writinger-based integral inequality, a suitable Lyapunov–Krasovskii functional was constructed, and a synchronization criterion for the considered system was derived in the form of LMIs. In order to cope with system uncertainties, the nonfragile controller was taken into account. Also, sampled-data controller is used to improve the effectiveness of the bandwidth usage. In order to achieve the benefits of both control techniques, the nonfragile sampled-data controller was considered for synchronization of semi-Markovian jumping neural networks and to assure that the error system is asymptotically stable. At last, numerical simulations are exhibited to validate the proposed technique.
Analysis of Contact Characteristics of Carbon Brush/Slip Ring under Eccentric Oscillation of Hydrogenerator Rotor
Authors: Zhao Xinze , Nie Yunfeng , Chen Ming , Qin Hongling , Xu Xiang
Published: October 2021

In this paper, the contact characteristics of the carbon brush/slip ring of the hydrogenerator under the eccentric vibration of the rotor are studied. The influence of spring parameters on the contact loss of the carbon brush/slip ring was studied by establishing the motion model of the carbon brush/slip ring for theoretical calculation and fitting the motion trajectory curve with MATLAB software. Studies have shown that the loss of contact is mainly related to the spring damping coefficient and the precompression. By optimizing these two parameters, the contact stability of the carbon brush on the ring surface of the slip ring can be improved. It provides a theoretical reference for the design and optimization of the parameters of the carbon brush/slip ring spring.
Association of Myocardial Enzyme Abnormality with Clinical Outcomes of Patients with COVID-19: A Retrospective Study
Authors: Zhang Qilin , Zheng Ziming , Zhang Yu
Published: October 2021

Background. It has been observed that COVID-19 may cause myocardial damage, but there are few detailed reports on myocardial enzyme abnormalities. Methods. In this retrospective study, we analyzed data from 157 consecutive laboratory-confirmed and hospitalized COVID-19 patients from Wuhan. We collected information on demographic and clinical characteristics, laboratory findings, and clinical outcomes. Logistic regression analysis was used to explore the risk factors associated with the severity of COVID-19. The association between myocardial enzyme abnormalities and the mortality was also investigated. Results. The mortality in abnormal myocardial enzyme group was obviously higher than the normal group (

P
<
0.001

). The majority of patients (

n
=
72

, 97.3%) with normal cardiac enzyme group were of the common novel coronavirus pneumonia (NCP) type, whereas half of the patients with cardiac enzyme abnormalities (

n
=
40

, 48.2%) developed critical and severe NCP type. The multivariable logistic regression analysis indicated that COVID-19 patients with increasing age (

P
=
0.035

), higher levels of CRP (

P
=
0.038

), and TNI (

P
=
0.036

) were associated with increased death than other patients. Conclusions. Myocardial enzyme abnormality and myocardial injury were associated with the severity and fatal outcomes of COVID-19. Clinicians should pay attention to the markers of myocardial injury in COVID-19 patients, especially those with older age, comorbidities, and inflammation.
Metolazone Add-On Therapy in Heart Failure: A Cohort Study from Persian Registry of Cardiovascular Disease/Heart Failure (PROVE/HF)
Authors: Rahimi Farzad , Vakhshoori Mehrbod , Heidarpour Maryam , Nouri Fatemeh , Heshmat-Ghahdarijani Kiyan , Fakhrolmobasheri Mohammad , Shafie Davood
Published: October 2021

Background. One of the strategies for overcoming diuretic resistance among heart failure (HF) patients is adding thiazide-type diuretics. The main aim of this article is to compare the adverse clinical outcomes, including death and re-hospitalization, among individuals suffering from severe acute decompensated HF (ADHF) that consumed furosemide or furosemide plus metolazone. Methods. This retrospective cohort study was done in the context of the Persian registry of cardiovascular disease (PROVE) from September 2017 to September 2018. One thousand and four hundred thirty-eight individuals (furosemide: 972 and furosemide plus metolazone: 466) with the final diagnosis of severe ADHF (left ventricular ejection fraction < 30%) were selected and followed for 10.3 ± 7.8 months. The association between two groups, as mentioned above, with the incidence of death and re-admission, was evaluated with different models. Results. The mean age of the study population was 68.19 ± 12.98 years. There was no significant relation in terms of death or re-hospitalization between patients with different diuretic regimens. After adjustment of potential confounders, we found that adding metolazone as an adjuvant HF therapy was not independently associated with death or re-hospitalization (hazard ratio (HR): 0.78,95% confidence interval (CI) = 0.59–1.03, P = 0.085, and odds ratio (OR): 0.80, 95% CI: 0.60–1.07, P = 0.135, respectively). Conclusion. Our findings revealed that adding metolazone in patients with furosemide resistance is not associated with higher morbidity and mortality. Therefore, usage of these two therapeutic agents could be a helpful strategy for severe HF patients.
Experimental Study on Vibration Reduction Technology of Hole-by-Hole Presplitting Blasting
Authors: Ma Jun , Li Xianglong , Wang Jianguo , Tao Zihao , Zuo Ting , Li Qiang , Zhang Xiaohua
Published: October 2021

In order to effectively reduce the disturbance of the precrack blasting vibration on slope rock mass, except paying attention to the damping effect of the precrack, it is also necessary to optimize the blasting parameters and initiation mode of the precrack itself. Based on the blasting theory and empirical formula, the parameters of presplitting blasting such as the hole diameter, hole spacing, charge decoupling coefficient, and line charge density were determined, and field tests of conventional pre-splitting blasting and presplitting blasting with precise delay and hole-by-hole initiation were carried out on the west slope of Buzhaoba. Regression analysis was carried out on the vibration monitoring data, and the blasting vibration attenuation regularity of slope particles was obtained. By comparing the monitored vibration velocity of the two presplitting blasting tests and the forecast results of theoretical calculation, the average reduction rate of the conventional same row blasting vibration is 26.40%, while that of the hole-by-hole blasting vibration can reach 41.45% with a half hole rate of 80.7% and an irregularity of about 130 mm. Results show that the effect of precise delay initiation between preholes based on the digital electronic detonator is better than that of the simultaneous initiation of preholes. Therefore, it is suggested that the hole-by-hole presplitting blasting technology should be applied in the excavation of boundary slope and the treatment of high and steep slope.
A Modified Transverse Process-Pedicle Approach Applied to Unilateral Extrapedicular Percutaneous Vertebroplasty
Authors: Zhuo Yunyun , Liu Liehua , Wang Haoming , Li Pei , Zhou Qiang , Liu Yugang
Published: October 2021

Objective. To introduce a modified transverse process-pedicle puncture technique applied to unilateral extrapedicular percutaneous vertebroplasty (PVP) for the treatment of osteoporotic lumbar vertebral compression fractures. Methods. A retrospective study was performed on 91 patients with osteoporotic vertebral compression fractures (OVCFs) who underwent unilateral extrapedicular PVP from June 2016 to September 2018. Lumbar and back pain was assessed through the visual analogue scale (VAS). Function recovery was assessed through the Oswestry disability index (ODI). Radiologic outcomes were assessed mainly on the basis of bone cement distribution and anterior vertebral height. Results. A total of 101 fractured vertebrae were successfully treated using the extrapedicular technique without any recognized clinical complications. The postoperative VAS and ODI values were significantly lower than the corresponding preoperative values

P
<
0.01

. Radiologic outcomes in all fractured vertebrae showed that the diffusion of bone cement could exceed the midline of the vertebral body. There was no significant difference between preoperative and postoperative anterior vertebral heights

P
<
0.05

. Conclusion. The modified transverse process-pedicle approach applied to unilateral extrapedicular percutaneous vertebroplasty is a simple, safe, and effective surgical method.
Fault Prediction of Centrifugal Pump Based on Improved KNN
Authors: Chen YunFei , Yuan Jianping , Luo Yin , Zhang Wenqi
Published: October 2021

To effectively predict the faults of centrifugal pumps, the idea of machine learning k‐nearest neighbor algorithm (KNN) was introduced into the traditional Mahalanobis distance fault discrimination, and an improved centrifugal pump fault prediction model of KNN based on the Mahalanobis distance is proposed. In this method, the Mahalanobis distance is used to replace the distance function in the conventional KNN algorithm. Grid search and cross‐validation are used to determine the optimal K value of the prediction model. A centrifugal pump test rig was established to solve three common faults of centrifugal pumps: cavitation, impeller damage, and machine seal damage, and the method was verified. The results show that this method can effectively distinguish the specific fault types of centrifugal pumps based on vibration signals, and the fault prediction accuracy of the off‐balance condition is up to 82%. This study provides a novel idea and method for centrifugal pump fault prediction and diagnosis and avoids the interaction between parameters when monitoring multiple parameters.
Characteristic Properties of Type-2 Smarandache Ruled Surfaces According to the Type-2 Bishop Frame in

E

3
Authors: Al-Dayel Ibrahim , Solouma E. M.
Published: October 2021

In this paper, we define and investigate a special kind of ruled surfaces called type-2 Smarandache ruled surfaces related to the type-2 Bishop frame in

E

3

. From this point and depending on the type-2 Bishop curvature, we provide the necessary and sufficient conditions that allow these surfaces to be developable in a minimal amount of time. Furthermore, an example is given to clear the results.
Feature Extraction of Music Signal Based on Adaptive Wave Equation Inversion
Authors: Gong Tianzhuo , Sun Sibing
Published: October 2021

The digitization, analysis, and processing technology of music signals are the core of digital music technology. There is generally a preprocessing process before the music signal processing. The preprocessing process usually includes antialiasing filtering, digitization, preemphasis, windowing, and framing. Songs in the popular wav format and MP3 format on the Internet are all songs that have been processed by digital technology and do not need to be digitalized. Preprocessing can affect the effectiveness and reliability of the feature parameter extraction of music signals. Since the music signal is a kind of voice signal, the processing of the voice is also applicable to the music signal. In the study of adaptive wave equation inversion, the traditional full-wave equation inversion uses the minimum mean square error between real data and simulated data as the objective function. The gradient direction is determined by the cross-correlation of the back propagation residual wave field and the forward simulation wave field with respect to the second derivative of time. When there is a big gap between the initial model and the formal model, the phenomenon of cycle jumping will inevitably appear. In this paper, adaptive wave equation inversion is used. This method adopts the idea of penalty function and introduces the Wiener filter to establish a dual objective function for the phase difference that appears in the inversion. This article discusses the calculation formulas of the accompanying source, gradient, and iteration step length and uses the conjugate gradient method to iteratively reduce the phase difference. In the test function group and the recorded music signal library, a large number of simulation experiments and comparative analysis of the music signal recognition experiment were performed on the extracted features, which verified the time-frequency analysis performance of the wave equation inversion and the improvement of the decomposition algorithm. The features extracted by the wave equation inversion have a higher recognition rate than the features extracted based on the standard decomposition algorithm, which verifies that the wave equation inversion has a better decomposition ability.