154 research outputs found
A Comparison of c-C₃H₂ and l-C₃H₂ in the Spiral Arm Clouds
Using the IRAM 30-m telescope, we observed molecular absorption lines from c-C₃H₂ produced in diffuse clouds toward the high-mass star forming regions W51 e1/e2 and W49N to determine the abundance ratio between the cyclic and linear isomers of C₃H₂ (N_c/N_l). The abundance ratio is found to be 3-5 in the sources where l-C₃H₂ was previously detected. A possible source of uncertainty in the determination of N_c/N_l is related to the estimate of N(c-C₃H₂). The main goal of this paper is verification of this hypothesis
A Comparison of c-C₃H₂ and l-C₃H₂ in the Spiral Arm Clouds
Using the IRAM 30-m telescope, we observed molecular absorption lines from c-C₃H₂ produced in diffuse clouds toward the high-mass star forming regions W51 e1/e2 and W49N to determine the abundance ratio between the cyclic and linear isomers of C₃H₂ (N_c/N_l). The abundance ratio is found to be 3-5 in the sources where l-C₃H₂ was previously detected. A possible source of uncertainty in the determination of N_c/N_l is related to the estimate of N(c-C₃H₂). The main goal of this paper is verification of this hypothesis
A Comparison of c-C_3H_2 and I-C_3H_2 in the Spiral Arm Clouds
Using the IRAM 30-m telescope, we observed molecular absorption lines from c-C_3H_2 produced in diffuse clouds toward the high-mass star forming regions W51 e1/e2 and W49N to determine the abundance ratio between the cyclic and linear isomers of C_3H_2 (N_c/N_l). The abundance ratio is found to be 3-5 in the sources where l-C_3H_2 was previously detected. A possible source of uncertainty in the determination of N_c/N_l is related to the estimate of N(c-C_3H_2). The main goal of this paper is verification of this hypothesis
Recent progress in thermoelectric MXene-based structures versus other 2D materials
Thermoelectricity is a next-generation solution for efficient waste heat
management. Although various thermoelectric materials exist, there is still a
lot of scope for advancement. Recently, two-dimensional (2D) materials,
including MXenes, showed promise as thermoelectric materials. The progress of
MXenes as magnificent thermoelectric materials is very well established in the
form of a tailor-made review. MXenes outstanding thermoelectric activity comes
from a unique band structure created from its atomically thin layers and the
defective surface of the external layers of atoms. Furthermore, the variety of
MXenes chemical composition and MXenes-based nanostructures facilitates the
research path based on energy band engineering, optimization, carrier
concentration and mobility. The thermoelectric efficiency of MXenes has been
mapped over the landscape of other 2D and traditional thermoelectric materials.
Meanwhile, MBenes, the latest family member of the flatland, exhibits an
incredible diversity of structures with additional crystal symmetries. Owing to
the orthorhombic crystal structure, an in-plane structural anisotropy, and
hence, the in-plane dependent thermoelectric properties are plausible. As a
future prospective, certain strategies that can enhance the thermoelectric
performance of MBenes have been presented. In addition, few insights and
challenges that have to be considered to overcome the limitations in the
thermoelectric field have been debated.Comment: 22 pages, 12 figures, 1 tabl
The role of NMDA receptor‐dependent activity of noradrenergic neurons in attention, impulsivity and exploratory behaviors
Metabolic control level and glucose variability in adolescents with type 1 diabetes during low and high-intensity exercise
OBJECTIVE
The main purpose of this study was to characterize the determinants of metabolic changes in young type 1 diabetes (T1DM) and to determine glycemic variability during low and high-intensity exercise.
PATIENTS AND METHODS
20 young male T1DM patients were divided into two subgroups characterized by levels of glycated hemoglobin (HbA1c): HbA1c7.3% (worse HbA1c subgroup, n=10). All participants performed a maximal oxygen uptake test and two efforts of various intensities (45 minutes of aerobic exercise and 30 minutes of mixed aerobic-anaerobic intensity exercise). Continuous glucose monitors (CGM) were used to control the glucose concentration.
RESULTS
Changes in biomarkers describing the metabolic response were similar in both groups. A comparison of applied efforts exhibited that maximal capacity effort resulted in the highest values of blood glucose (BG) at the end (150.9-160.6 mg/dl) and 1 hour after the exercise (140.2-161.3 mg/dl). BG concentration before, during, 1 hour, and 24 hours after each exercise was insignificantly higher in the worse Hb1Ac group.
CONCLUSIONS
HbA1c levels are insufficient to confirm whether the applied effort is performed in acceptable glycemic values. The CGM monitors allow for precise control of BG variations and accurate planning of physical activity by adjusting the insulin and carbohydrate consumption dose
Postępowanie w chorobach tarczycy u kobiet w ciąży
The management of thyroid disorders during pregnancy is one of the most frequently disputed problems in modern endocrinology. It is
widely known that thyroid dysfunction may result in subfertility, and, if inadequately treated during pregnancy, may cause obstetrical
complications and influence fetal development.
The 2007 Endocrine Society Practice Guideline endorsed with the participation of the Latino America Thyroid Association, the American
Thyroid Association, the Asia and Oceania Thyroid Association and the European Thyroid Association, greatly contributed towards uniformity
of the management of thyroid disorders during pregnancy and postpartum. Despite the tremendous progress in knowledge on
the mutual influence of pregnancy and thyroid in health and disease, there are still important areas of uncertainty. There have been at
least a few important studies published in the last 3 years, which influenced the thyroidal care of the expecting mother. It should also be
remembered that guidelines may not always be universally applied in all populations with different ethnical, socio-economical, nutritional
(including iodine intake) background or exposed to different iodine prophylaxis models.
The Task Force for development of guidelines for thyroid dysfunction management in pregnant women was established in 2008. The expert
group has recognized the following tasks: development of the coherent model of the management of thyroid dysfunction in pregnant
women, identification of the group of women at risk of thyroid dysfunction, who may require endocrine care in the preconception period,
during pregnancy and postpartum – that is in other words, the development of Polish recommendations for targeted thyroid disorder case
finding during pregnancy, and the development of Polish trimester-specific reference values of thyroid hormones.
Comprehensive Polish guidelines developed by the Task Force are to systematize the management of the thyroid disorders in pregnant
women in Poland.
(Pol J Endocrinol 2011; 62 (4): 362–381)Jednym z aktualnie szeroko dyskutowanych problemów współczesnej endokrynologii jest opieka tyreologiczna nad kobietą ciężarną.
Powszechnie wiadomo, że dysfunkcja tarczycy może być przyczyną zaburzeń płodności, a nieleczona prawidłowo w czasie ciąży zwiększa
ryzyko powikłań położniczych oraz ma wpływ na rozwój płodu.
Opublikowane w 2007 roku wytyczne Towarzystwa Endokrynologicznego (Endocrine Society), opracowane przy współudziale Towarzystwa
Tyreologicznego Ameryki Łacińskiej (LATS), Towarzystwa Tyreologicznego Azji i Oceanii (AOTA), Amerykańskiego Towarzystwa
Tyreologicznego (ATA) oraz Europejskiego Towarzystwa Tyreologicznego (ETA), w dużym stopniu usystematyzowały zasady postępowania
w chorobach tarczycy w czasie ciąży i w okresie poporodowym. Pomimo ogromnego postępu wiedzy na temat wzajemnego wpływu
ciąży i funkcji gruczołu tarczowego w zdrowiu i chorobie, jaki osiągnięto w ciągu ostatnich kilkunastu lat, nadal pewne obszary wymagają
dalszych badań. W ciągu 3 lat, które minęły od publikacji wytycznych, przybyło danych, które wpłynęły na niektóre zasady prowadzenia
ciężarnej z chorobą tarczycy. Wytyczne nie zawsze mają charakter uniwersalny i nie mogą być w prosty sposób transponowane na społeczeństwa
zróżnicowane etnicznie i ekonomicznie, o odmiennych zwyczajach dietetycznych, w tym w spożyciu nośników jodu, oraz
stosujące odmienne modele profilaktyki jodowej.
W 2008 roku powołano Zespół Ekspertów do spraw Opieki Tyreologicznej w Ciąży. Za cele prac Zespołu przyjęto: opracowanie modelu
opieki nad ciężarną z zaburzeniami funkcji tarczycy, określenie grupy kobiet z ryzykiem zaburzeń funkcji tarczycy wymagających oceny
tyreologicznej podczas planowania ciąży, w trakcie jej trwania oraz w okresie poporodowym — czyli przygotowanie polskich wskazań
do badań przesiewowych oraz ustalenie wartości referencyjnych stężeń hormonów tarczycy w poszczególnych trymestrach ciąży.
Opracowane przez Zespół wytyczne systematyzują zasady opieki tyreologicznej nad kobietą ciężarną w Polsce.
(Endokrynol Pol 2011; 62 (4): 362–381
Influence of mitochondrial genome rearrangement on cucumber leaf carbon and nitrogen metabolism
The MSC16 cucumber (Cucumis sativus L.) mitochondrial mutant was used to study the effect of mitochondrial dysfunction and disturbed subcellular redox state on leaf day/night carbon and nitrogen metabolism. We have shown that the mitochondrial dysfunction in MSC16 plants had no effect on photosynthetic CO2 assimilation, but the concentration of soluble carbohydrates and starch was higher in leaves of MSC16 plants. Impaired mitochondrial respiratory chain activity was associated with the perturbation of mitochondrial TCA cycle manifested, e.g., by lowered decarboxylation rate. Mitochondrial dysfunction in MSC16 plants had different influence on leaf cell metabolism under dark or light conditions. In the dark, when the main mitochondrial function is the energy production, the altered activity of TCA cycle in mutated plants was connected with the accumulation of pyruvate and TCA cycle intermediates (citrate and 2-OG). In the light, when TCA activity is needed for synthesis of carbon skeletons required as the acceptors for NH4+ assimilation, the concentration of pyruvate and TCA intermediates was tightly coupled with nitrate metabolism. Enhanced incorporation of ammonium group into amino acids structures in mutated plants has resulted in decreased concentration of organic acids and accumulation of Glu
The influence of salinity on the effects of Multi-walled carbon nanotubes on polychaetes
Salinity shifts in estuarine and coastal areas are becoming a topic of concern and are one of the main factors influencing nanoparticles behaviour in the environment. For this reason, the impacts of multiwalled carbon nanotubes (MWCNTs) under different seawater salinity conditions were evaluated on the common ragworm Hediste diversicolor, a polychaete species widely used as bioindicator of estuarine environmental quality. An innovative method to assess the presence of MWCNT aggregates in the sediments was used for the first time. Biomarkers approach was used to evaluate the metabolic capacity, oxidative status and neurotoxicity of polychaetes after long-term exposure. The results revealed an alteration of energy-related responses in contaminated polychaetes under both salinity conditions, resulting in an increase of metabolism and expenditure of their energy reserves (lower glycogen and protein contents). Moreover, a concentration-dependent toxicity (higher lipid peroxidation, lower ratio between reduced and oxidized glutathione and activation of antioxidant defences and biotransformation mechanisms) was observed in H. diversicolor, especially when exposed to low salinity. Additionally, neurotoxicity was observed by inhibition of Cholinesterases activity in organisms exposed to MWCNTs at both salinities.publishe
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