Use of ultrasound densitometry for the assess of structural and functional disorders of bone tissue and prediction of fractures risk

To determine the dependence of lumbar spine compression degree on BMD state and the patients’ age. The relationship of BMD state, the patients’ age and the degree of compression of the vertebrae were studied. Correlation and regression analysis of the relationship between SOS index, score of compression and patients' age have been examined. Results. The data obtained allowed us to develop a mathematical model for predicting BMD reduction and the severity of vertebral compression fractures. Conclusions. Ultrasonic indexes of bone mineral density may be used not only for its screening assessment in general population of different ages, but also in assessing the degree of structural and functional changes of BT, predicting the severity of low-energy osteoporosis fractures. It will help to assign treatment in preclinical stage, and carry out prevention of compression fractures

A next-generation inverse-geometry spallation-driven ultracold neutron source

The physics model of a next-generation spallation-driven high-current ultracold neutron (UCN) source capable of delivering an extracted UCN rate of around an-order-of-magnitude higher than the strongest proposed sources, and around three-orders-of-magnitude higher than existing sources, is presented. This UCN-current-optimized source would dramatically improve cutting-edge UCN measurements that are currently statistically limited. A novel "Inverse Geometry" design is used with 40 L of superfluid $^4$He (He-II), which acts as a converter of cold neutrons (CNs) to UCNs, cooled with state-of-the-art sub-cooled cryogenic technology to $\sim$1.6 K. Our design is optimized for a 100 W maximum heat load constraint on the He-II and its vessel. In our geometry, the spallation target is wrapped symmetrically around the UCN converter to permit raster scanning the proton beam over a relatively large volume of tungsten spallation target to reduce the demand on the cooling requirements, which makes it reasonable to assume that water edge-cooling only is sufficient. Our design is refined in several steps to reach $P_{UCN}=2.1\times10^9\,/$s under our other restriction of 1 MW maximum available proton beam power. We then study effects of the He-II scattering kernel as well as reductions in $P_{UCN}$ due to pressurization to reach $P_{UCN}=1.8\times10^9\,/$s. Finally, we provide a design for the UCN extraction system that takes into account the required He-II heat transport properties and implementation of a He-II containment foil that allows UCN transmission. We estimate a total useful UCN current from our source of $R_{use}=5\times10^8\,/$s from a 18 cm diameter guide 5 m from the source. Under a conservative "no return" approximation, this rate can produce an extracted density of $>1\times10^4\,/$cm$^3$ in $<$1000~L external experimental volumes with a $^{58}$Ni (335 neV) cut-off potential.Comment: Submitted to Journal of Applied Physic

Therapy with vitamin D metabolits of structural and functional changes in bone tissue of working postmenopausal women with ostearcopenia

The prevalence of osteoporosis and vitamin D deficiency in postmenopausal women working under harmful labour conditions has been examined. Reduced bone mineral density was revealed in 85% of the persons under observation, the incidence of OP was 35%, sarcopenia (SP) – 35%. Vitamin D deficiency was foundin 91.3% ofthe workers, at the same time severe VD deficiency was observedin 32.9%, VD deficiency – in 7.5%,and the optimal level of vitamin D was observedin 1.2%of cases. 79 PM women with OP aged 50 – 60 y. o.(meanage – (55.7 ± 0.9) years), working at harmful conditions of the working environment with an average length of service 26.14 ± 0.91years have been examined. Clinical group A (n = 30) received cholecalciferol at a dose of 2000 IU (4 drops) per day and alfacalcidol 1 μg (1 capsule) once a dayfor a year.This resulted in a positive effect on the level of 25(OH)D. Тhe complex appointment of cholecalciferol and alfacalcidol reduced thelevel of PTH and confirmed the role of VD deficiency in the progress of secondary hyperparathyroidism.The data obtained revealed a slowing of the effect of VD onosteoclastogenesis. Decrease of bone resorption marker CTx in the women under examination confirmed the latter

ОПТИМІЗАЦІЯ ПАРАМЕТРІВ ПСЕВДОЗРІДЖЕНОГО ШАРУ З ВРАХУВАННЯМ «ЕКВІВАЛЕНТНОГО ДІАМЕТРА КАНАЛІВ»

Priority&nbsp;ways to optimize&nbsp;the parameters of&nbsp;the fluidized bed&nbsp;(FB)&nbsp;system&nbsp;solid - liquid&nbsp;(S-S) or&nbsp;solid -&nbsp;gas (S-G).&nbsp;Formulas&nbsp;6&nbsp;to optimize the&nbsp;ratio&nbsp;«equivalent&nbsp;diameter&nbsp;channels»&nbsp;in&nbsp;&nbsp;to the average&nbsp;thickness of the&nbsp;laminar&nbsp;boundary&nbsp;layer&nbsp;(LBL) arisingseparate&nbsp;solid&nbsp;particles&nbsp;around&nbsp;in&nbsp;FB.&nbsp;Presented&nbsp;also&nbsp;inequalities&nbsp;optimization&nbsp;parameters&nbsp;in FB&nbsp;for&nbsp;system&nbsp;S-S&nbsp;or&nbsp;S-G,&nbsp;in&nbsp;which comprises&nbsp;themselves&nbsp;in&nbsp;the parameter&nbsp;optimization,&nbsp;which&nbsp;&nbsp;of withdrawal&nbsp;by us&nbsp;earlier&nbsp;[1,2], as well as&nbsp;optymalnuyuinhomogeneities&nbsp;optymalnuyu&nbsp;height&nbsp;and&nbsp;FB. It is shown that&nbsp;the calculation formula&nbsp;vivedennye&nbsp;optimization parameter&nbsp;in&nbsp;diffusion processes B,&nbsp;the optimal&nbsp;average&nbsp;thickness of&nbsp;LBL&nbsp;ratios&nbsp;«equivalent&nbsp;diameter of the channels»&nbsp;in&nbsp;FB&nbsp;to the average thickness&nbsp;of LBL&nbsp;can be employed&nbsp;to minimize energy&nbsp;in a&nbsp;thermal&nbsp;mass transfer processes,&nbsp;including&nbsp;drying,&nbsp;extraction, et al.&nbsp;field&nbsp;of gravitational and&nbsp;centrifugal forces.&nbsp;Calculate&nbsp;optimization criterion&nbsp;B&nbsp;ratio&nbsp;"equivalent diameter of&nbsp;the channel" in the village&nbsp;to the average thickness&nbsp;of LBL&nbsp;in the areasof the curve&nbsp;fluidization&nbsp;OK&nbsp;and AC&nbsp;shown that&nbsp;these&nbsp;relationships&nbsp;can&nbsp;optimize the process of&nbsp;fluidization&nbsp;in the&nbsp;S-S or&nbsp;S-G,&nbsp;based on the&nbsp;numerical&nbsp;values of these&nbsp;ratios.&nbsp;Depending&nbsp;on the conditions of&nbsp;the fluidization&nbsp;inequality&nbsp;7 has&nbsp;proposed&nbsp;optimization option&nbsp;in&nbsp;FB&nbsp;&nbsp;for&nbsp;the LBL&nbsp;or&nbsp;in the field&nbsp;or&nbsp;gravitatsionnіh&nbsp;tsentrobezhnіh&nbsp;forces,&nbsp;respectively. &nbsp;Обозначены приоритетние пути оптимизации параметров псевдоожиженного слоя (ПОС)  в системе твердое тело – жидкость (ТТ-Ж) или твердое тело – газ (ТТ-Г). Виведена формула 6 для оптимизации соотношений «еквивалентного диаметра каналов» в  ПОС к средней толщине ламинарного приповерхностного слоя (ЛПС), что возникает вокруг отдельной твердой частицы в ЛПС. Представлено также неравенство параметров оптимизации в ПОС для системы ТТ-Ж или ТТ-Г, которое включет в себя параметр оптимизации В, который виведен нами раньше [1,2], а также оптимальную неоднородность и оптимальнуювисоту ПОС. Показано, что виведенные формулы расчета параметра оптимизации диффузионных процессов В, средней оптимальной толщины ЛПС, соотношений «эквивалентного диаметра каналов» в ПОС к средней толщине ЛПС могутприменяться для минимизации энергозатрат в условиях тепло- массообменных процессов, в частности сушки, экстрагирования и др. в поле гравитационных и центробежных сил. Расчитаны критерий оптимизации В, соотношения «эквивалентного диаметра каналов» в ПОС к средней толщине ЛПС на участках кривой псевдоожижения ОК и КВ и показано,что за этими соотношениями можно оптимизировать процесс псевдоожижения в системе ТТ-Ж или ТТ-Г, исходя из числовых значений этих соотношений. В зависимости от условий псевдоожижения  предложенное неравенство 7 имеет параметр оптимизации В или Вц  для ПОС в поле гравитационніх или центробежніх сил, соответственно.Визначені пріоритетні шляхи оптимізації параметрів псевдозрідженого шару (ПЗШ)&nbsp; в системі тверде тіло – рідина (ТТ-Р) або тверде тіло – газ (ТТ-Г). Виведена формула 6&nbsp;для оптимізації співвідношень «еквівалентного діаметра каналів» у ПЗШ до середньої товщини ламінарного приповерхневого шару (ЛПШ), що виникає навколо окремої твердої частинки в ПЗШ.. Представлена також нерівність параметрів оптимізації в ПЗШ для системи ТТ-Р або ТТ-Г, яка включає параметр оптимізації В, що виведений нами раніше [1,2],&nbsp;а також&nbsp;оптимальну неоднорідність і оптимальну висоту&nbsp; ПЗШ. Показано, що виведені формули розрахунку&nbsp;параметра оптимізації дифузійних процесів В, середньої оптимальної товщини ЛПШ, співвідношень «еквівалентного діаметра каналів» у ПЗШ до середньої товщини ЛПШ можуть застосовуватися для мінімізації енерговитрат в умовах тепло- масообмінних процесів, зокрема сушіння, екстрагування та інш в полі гравітаційних та відцентрових сил. Розраховані критерій оптимізації В, співвідношення «еквівалентного діаметра каналів» у ПЗШ до середньої товщини ЛПШ на ділянках кривої псевдозрідження ОК і КВ і показано, що за&nbsp; цими співвідношеннями можна оптимізувати процес псевдозрідження в системі ТТ-Р або ТТ-Г, виходячи з числових значень цих співвідношень.&nbsp;Залежно від умовпсевдозрідження&nbsp;запропонована&nbsp;нерівність&nbsp;7&nbsp;має параметр&nbsp;оптимізації&nbsp;В або&nbsp;&nbsp;Вц&nbsp;для&nbsp;ПЗШ&nbsp;в&nbsp;полі&nbsp;гравітаційних&nbsp;або&nbsp;відцентрових&nbsp;сил,&nbsp;відповідно. &nbsp

How predation and landscape fragmentation affect vole population dynamics

Background: Microtine species in Fennoscandia display a distinct north-south gradient from regular cycles to stable populations. The gradient has often been attributed to changes in the interactions between microtines and their predators. Although the spatial structure of the environment is known to influence predator-prey dynamics of a wide range of species, it has scarcely been considered in relation to the Fennoscandian gradient. Furthermore, the length of microtine breeding season also displays a north-south gradient. However, little consideration has been given to its role in shaping or generating population cycles. Because these factors covary along the gradient it is difficult to distinguish their effects experimentally in the field. The distinction is here attempted using realistic agent-based modelling. Methodology/Principal Findings: By using a spatially explicit computer simulation model based on behavioural and ecological data from the field vole (Microtus agrestis), we generated a number of repeated time series of vole densities whose mean population size and amplitude were measured. Subsequently, these time series were subjected to statistical autoregressive modelling, to investigate the effects on vole population dynamics of making predators more specialised, of altering the breeding season, and increasing the level of habitat fragmentation. We found that fragmentation as well as the presence of specialist predators are necessary for the occurrence of population cycles. Habitat fragmentation and predator assembly jointly determined cycle length and amplitude. Length of vole breeding season had little impact on the oscillations. Significance: There is good agreement between our results and the experimental work from Fennoscandia, but our results allow distinction of causation that is hard to unravel in field experiments. We hope our results will help understand the reasons for cycle gradients observed in other areas. Our results clearly demonstrate the importance of landscape fragmentation for population cycling and we recommend that the degree of fragmentation be more fully considered in future analyses of vole dynamics

Non-invasive optical method for evaluating the oxygen status in breast neoplasms

The paper presents the results from a study of the breast oxygen status by diffuse optical tomography (DOT). Detection of breast tissue at wavelengths of 684, 794, and 850 nm could provide information on the distribution of basic tissue chromophores: oxygenized and deoxygenized hemoglobin. Normal breast tissue was characterized by the even distribution of these compounds and stabilization of their level. In breast cancer, the distribution of oxy- and deoxyhemoglobin was noted for uneven distribution and blood oxygen saturation was lower in the projection of a tumor nodule. The blood oxygen saturation data obtained by DOT demonstrate physiological differ- ences between normal and tumor tissues in different tumor areas

The functional response of a generalist predator

Peer reviewedPublisher PD

An Experimental Field Study of Delayed Density Dependence in Natural Populations of Aedes albopictus

Aedes albopictus, a species known to transmit dengue and chikungunya viruses, is primarily a container-inhabiting mosquito. The potential for pathogen transmission by Ae. albopictus has increased our need to understand its ecology and population dynamics. Two parameters that we know little about are the impact of direct density-dependence and delayed density-dependence in the larval stage. The present study uses a manipulative experimental design, under field conditions, to understand the impact of delayed density dependence in a natural population of Ae. albopictus in Raleigh, North Carolina. Twenty liter buckets, divided in half prior to experimentation, placed in the field accumulated rainwater and detritus, providing oviposition and larval production sites for natural populations of Ae. albopictus. Two treatments, a larvae present and larvae absent treatment, were produced in each bucket. After five weeks all larvae were removed from both treatments and the buckets were covered with fine mesh cloth. Equal numbers of first instars were added to both treatments in every bucket. Pupae were collected daily and adults were frozen as they emerged. We found a significant impact of delayed density-dependence on larval survival, development time and adult body size in containers with high larval densities. Our results indicate that delayed density-dependence will have negative impacts on the mosquito population when larval densities are high enough to deplete accessible nutrients faster than the rate of natural food accumulation

Cognitive impairment restoration in patients suffered with stroke during the post-COVID period

Frequency of vascular complications, including strokes, in patients suffered from COVID-19 infection is known to be increased up to 8 times, especially compared with influenza. The purpose: to investigate the fundamental mechanisms of brain ischemia in the patients with mnestic dysfunctions who previously underwent COVID-19 through pharmacocorrection via Phenibut (γ-amino-β-phenylbutyric acid hydrochloride) and magnetic therapy in the early recovery period of ischemic stroke. The authors describe the possibilities of cognitive rehabilitation for people who have had ischemic stroke in the post-COVID period. Considering that the presence of mnestic dysfunctions has a negative impact on the process of rehabilitation of cerebral accidents, the fundamental mechanisms of brain ischemia in patients with mnestic dysfunctions in the early recovery period in patients who have undergone COVID-19 have been studied through pharmacocorrection via Phenibut (γ-amino- β-phenylbutyric acid hydrochloride) and magnetic therapy. 46 patients aged 40 to 60 years were examined. A comparative study of three randomized clinical groups of patients with separate and complex use of Phenibut and magnetic stimulation. The effectiveness of the proposed therapy in restoring executive functions was established on the basis of indicators of the MMSE scale, the test for the study of frontal dysfunction – FAB, regression of depressive symptoms and is characterized by a decrease in the score on the GDS scale. The authors conclude that mnestic disorders are a functional "target" in cerebral ischemia in the postCOVID period, which requires close attention in relation to pharmacocorrection methods and comprehensive rehabilitation and further research, including the elucidate the pathogenetic mechanisms of cerebral ischemia

Life path analysis: scaling indicates priming effects of social and habitat factors on dispersal distances

1. Movements of many animals along a life-path can be separated into repetitive ones within home ranges and transitions between home ranges. We sought relationships of social and environmental factors with initiation and distance of transition movements in 114 buzzards Buteo buteo that were marked as nestlings with long-life radio tags. 2. Ex-natal dispersal movements of 51 buzzards in autumn were longer than for 30 later in their first year and than 35 extra-natal movements between home ranges after leaving nest areas. In the second and third springs, distances moved from winter focal points by birds that paired were the same or less than for unpaired birds. No post-nuptial movement exceeded 2 km. 3. Initiation of early ex-natal dispersal was enhanced by presence of many sibs, but also by lack of worm-rich loam soils. Distances travelled were greatest for birds from small broods and with relatively little short grass-feeding habitat near the nest. Later movements were generally enhanced by the absence of loam soils and short grassland, especially with abundance of other buzzards and probable poor feeding habitats (heathland, long grass). 4. Buzzards tended to persist in their first autumn where arable land was abundant, but subsequently showed a strong tendency to move from this habitat. 5. Factors that acted most strongly in ½-km buffers round nests, or round subsequent focal points, usually promoted movement compared with factors acting at a larger scale. Strong relationships between movement distances and environmental characteristics in ½-km buffers, especially during early ex-natal dispersal, suggested that buzzards became primed by these factors to travel far. 6. Movements were also farthest for buzzards that had already moved far from their natal nests, perhaps reflecting genetic predisposition, long-term priming or poor habitat beyond the study area