bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abnormal red blood cell morphological changes in thalassaemia associated with iron overload and oxidative stress
Authors: Chaichompoo Pornthip , Qillah Ariz , Sirankapracha Pornpan , Kaewchuchuen Jirada , Rimthong Poramate , Paiboonsukwong Kittiphong , Fucharoen Suthat , Svasti Saovaros , Worawichawong Suchin 
Published: April 2019

AimsIron overload is a major factor contributing to the overall pathology of thalassaemia, which is primarily mediated by ineffective erythropoiesis and shorter mature red blood cell (RBC) survival. Iron accumulation in RBCs generates reactive oxygen species (ROS) that cause cellular damage such as lipid peroxidation and RBC membrane deformation. Abnormal RBCs in patients with thalassaemia are commonly known as microcytic hypochromic anaemia with poikilocytosis. However, iron and ROS accumulation in RBCs as related to RBC morphological changes in patients with thalassaemia has not been reported.MethodsTwenty-one patients with thalassaemia, including HbH, HbH with Hb Constant Spring and β-thalassaemia/HbE (splenectomy and non-splenectomy) genotypes, and five normal subjects were recruited. RBC morphology was analysed by light and scanning electron microscopy. Systemic and RBC iron status and oxidative stress were examined.ResultsDecreased normocytes were observed in the samples of patients with thalassaemia, with RBC morphological abnormality being related to the type of disease (α-thalassaemia or β-thalassaemia) and splenic status. Target cells and crenated cells were mainly found in splenectomised patients with β-thalassaemia/HbE, while target cells and teardrop cells were found in non-splenectomised patients. Patients with thalassaemia had high levels of serum ferritin, red cell ferritin and ROS in RBCs compared with normal subjects (p<0.05). Negative correlations between the amount of normocytes and serum ferritin (rs=−0.518, p=0.011), red cell ferritin (rs=−0.467, p=0.025) or ROS in RBCs (rs=−0.672, p<0.001) were observed.ConclusionsIron overload and its consequent intracellular oxidative stress in RBCs were associated with reduce normocytes in patients with thalassaemia.
Prevalence of antenatal depression in South Asia: a systematic review and meta-analysis
Authors: Mahendran Rahini , Puthussery Shuby , Amalan Mahendran 
Published: April 2019

ObjectiveTo estimate the prevalence of antenatal depression in South Asia and to examine variations by country and study characteristics to inform policy, practice and future research.MethodsWe conducted a comprehensive search of 13 databases including international databases and databases covering scientific literature from South Asian countries in addition to Google Scholar and grey sources from 1 January 2007 to 31 May 2018. Studies reporting prevalence estimates of antenatal depression using a validated diagnostic/screening tool were identified, screened, selected and appraised. Primary outcome was proportion (%) of pregnant women identified as having antenatal depression.ResultsThirty-three studies involving 13 087 pregnant women were included in the meta-analysis. Twelve studies were rated as high quality and 21 studies were of moderate quality. Overall pooled prevalence of antenatal depression was 24.3 % (95% Confidence Interval (CI) 19.03 to 30.47). Studies showed a high degree of heterogeneity (I2=97.66%) and evidence of publication bias (p=0.668). Prevalence rates for India (17.74%, 95% CI 11.19 to 26.96) and Sri Lanka (12.95%, 95% CI 8.29 to 19.68) were lower compared with the overall prevalence, whereas prevalence rates for Pakistan (32.2%, 95% CI 23.11 to 42.87) and Nepal (50%, 95% CI 35.64 to 64.36) were higher.ConclusionsWhile robust prevalence studies are sparse in most South Asian countries, available data suggest one in four pregnant women is likely to experience antenatal depression in the region. Findings highlight the need for recognition of the issue in health policy and practice and for resource allocation for capacity building at regional and national levels for prevention, diagnosis and treatment.
Preparing for PrEP: estimating the size of the population eligible for HIV pre-exposure prophylaxis among men who have sex with men in England
Authors: Mitchell Holly D , Desai Sarika , Mohammed Hamish , Ong Koh Jun , Furegato Martina , Hall Victoria , Desai Monica , Saunders John Michael , Hughes Gwenda , Field Nigel , Gill O Noel 
Published: April 2019

ObjectivesThe size of the population of men who have sex with men (MSM) who may be eligible for HIV pre-exposure prophylaxis (HIV-PrEP) in England remains unknown. To plan for a national PrEP implementation trial, we estimated the number of MSM attending sexual health clinics (SHCs) that may be eligible for HIV-PrEP in England.MethodsSexually transmitted infection (STI) surveillance data from 2010 to 2015 from the GUMCAD surveillance system were used to estimate the annual number of HIV-negative MSM who may be eligible for HIV-PrEP in England. Based on national eligibility criteria, we identified HIV-negative MSM attending SHCs with a HIV-negative test in the past year and used diagnosed bacterial STI (past year) in this group as a proxy for condomless sex and eligibility for HIV-PrEP. We estimated HIV incidence per 100 person-years (py) in these groups in 2014.ResultsDuring 2010–2015, the number of HIV-negative MSM attending SHCs with a HIV-negative test in the past year doubled from 14 643 to 29 023, and HIV incidence in this group was 1.9 (95% CI 1.6 to 2.2) per 100 py in 2014. In the same period, the subgroup with a bacterial STI diagnosis (past year), and therefore considered potentially eligible for HIV-PrEP in this analysis, increased from 4365 (30%) to 10 276 (35%). HIV incidence in this subgroup was 3.3 (95% CI 2.7 to 4.0) per 100 py in 2014.ConclusionsIn 2015, approximately 10 000 HIV-negative MSM were considered potentially eligible for HIV-PrEP based on clinic history in GUMCAD. These data were used to inform the initial recruitment target for the PrEP Impact Trial and will inform future evaluations at a population level.
Low temperature synthesis of wollastonite using sol–gel combustion method: In vitro bioactivity evaluation
Authors: Riaz Madeeha , Zia Rehana , Aslam Snudia , Qamar Alliya , Hussain Tousif , Anjum Safia 
Published: April 2019

In this paper, low temperature, economical sol–gel combustion method was adopted to synthesize wollastonite ceramic. Calcium nitrate tetrahydrate and tetraethyl orthosilicate were taken as source for Ca and Si, while citric acid and nitric acid were used as chelating/combustion agents. The yielded powder calcined at 600[Formula: see text]C for 4 h was characterized by FTIR, XRD and SEM techniques. Results showed that the citrate combustion method was the most efficient method to prepare wollastonite at low temperature. Moreover, in vitro bioactivity test performed in simulated body fluid (SBF) showed good bioactivity of synthesized wollastonite ceramics.
Effect of [Li]/[Nb] ratios on segregation coefficient and dopant occupancy of In:Yb:Nd:LiNbO3 crystals
Authors: Dai Li , Shao Yu , Han Xianbo , Liu Chunrui , Wang Luping 
Published: April 2019

A series of [Formula: see text] crystals with various [Li]/[Nb] ratios (0.946, 1.05, 1.20 and 1.38) were grown by the Czochralski method. They were analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES). As the [Li]/[Nb] ratio increases in the melt, the segregation coefficients of [Formula: see text] and [Formula: see text] ions increase, while the segregation coefficient of [Formula: see text] ions decrease. The [Li]/[Nb] ratio in the crystal of sample [Formula: see text] is 0.996, which is near stoichiometric. The dopant occupancy with different [Li]/[Nb] ratios was analyzed by IR transmission spectrum and UV-VIS-NIR spectrum. When the [Li]/[Nb] ratio reaches 1.20, the absorption peak at [Formula: see text] indicates that the threshold concentration of [Formula: see text] is 1 mol.% in the sample [Formula: see text].
Deep Learning Predicts Lung Cancer Treatment Response from Serial Medical Imaging
Authors: Xu Yiwen , Hosny Ahmed , Zeleznik Roman , Parmar Chintan , Coroller Thibaud , Franco Idalid , Mak Raymond H. , Aerts Hugo J.W.L. 
Published: April 2019

Abstract

Purpose:
Tumors are continuously evolving biological systems, and medical imaging is uniquely positioned to monitor changes throughout treatment. Although qualitatively tracking lesions over space and time may be trivial, the development of clinically relevant, automated radiomics methods that incorporate serial imaging data is far more challenging. In this study, we evaluated deep learning networks for predicting clinical outcomes through analyzing time series CT images of patients with locally advanced non–small cell lung cancer (NSCLC).
Experimental Design: Dataset A consists of 179 patients with stage III NSCLC treated with definitive chemoradiation, with pretreatment and posttreatment CT images at 1, 3, and 6 months follow-up (581 scans). Models were developed using transfer learning of convolutional neural networks (CNN) with recurrent neural networks (RNN), using single seed-point tumor localization. Pathologic response validation was performed on dataset B, comprising 89 patients with NSCLC treated with chemoradiation and surgery (178 scans).

Results:
Deep learning models using time series scans were significantly predictive of survival and cancer-specific outcomes (progression, distant metastases, and local-regional recurrence). Model performance was enhanced with each additional follow-up scan into the CNN model (e.g., 2-year overall survival: AUC = 0.74, P &lt; 0.05). The models stratified patients into low and high mortality risk groups, which were significantly associated with overall survival [HR = 6.16; 95% confidence interval (CI), 2.17–17.44; P &lt; 0.001]. The model also significantly predicted pathologic response in dataset B (P = 0.016).

Conclusions:
We demonstrate that deep learning can integrate imaging scans at multiple timepoints to improve clinical outcome predictions. AI-based noninvasive radiomics biomarkers can have a significant impact in the clinic given their low cost and minimal requirements for human input.
Postinfarction Myocardial Calcifications on Cardiac Computed Tomography
Authors: Alyesh Daniel M. , Siontis Konstantinos C. , Sharaf Dabbagh Ghaith , Yokokawa Miki , Njeim Mario , Patel Smita , Morady Fred , Bogun Frank 
Published: April 2019

Background:
Postinfarction ventricular tachycardia (VT) generally involves myocardial fibers surrounded by scar. Calcification of scar tissue has been described, but the relationship between calcifications within endocardial scar and VTs is unclear. The purpose of this study was to assess the prevalence of myocardial calcifications as detected by cardiac computed tomography (CT) and the benefit for mapping and ablation focusing on nontolerated VTs.

Methods:
Fifty-six consecutive postinfarction patients had a cardiac CT performed before a VT ablation procedure. Another 56 consecutive patients with prior infarction without VT who had cardiac CTs served as a control group.

Results:

Myocardial calcifications were identified in 39 of 56 patients (70%) in the postinfarction group with VT, compared with 6 of 56 patients (11%) in the control group without VT. Calcifications were associated with VT when compared with a control group. A calcification volume of 0.538 cm
3
distinguished patients with calcification-associated VT from patients without calcification-associated VTs (area under the curve, 0.87; sensitivity, 0.87; specificity, 0.88). Myocardial calcifications corresponded to areas of electrical nonexcitability and formed a border for reentry circuits for 49 VTs (33% of all VTs for which target sites were identified) in 24 of 39 patients (62%) with myocardial calcifications. A nonconfluent calcification pattern was associated with VT target sites independent of calcification volume (
P
=0.01).

Conclusions:
Myocardial calcifications detected by cardiac CT in patients with prior infarction are associated with VT. The calcifications correspond to areas of unexcitability and represent a fixed boundary of reentry circuits that can be visualized by CT. Calcifications correspond to effective ablation sites in >1/3 of patients with postinfarction VT.
Local Conduction Velocity in the Presence of Late Gadolinium Enhancement and Myocardial Wall Thinning
Authors: Jang Jihye , Whitaker John , Leshem Eran , Ngo Long H. , Neisius Ulf , Nakamori Shiro , Pashakhanloo Farhad , Menze Bjoern , Manning Warren J. , Anter Elad , Nezafat Reza 
Published: April 2019

Background:
Conduction velocity (CV) is an important property that contributes to the arrhythmogenicity of the tissue substrate. The aim of this study was to investigate the association between local CV versus late gadolinium enhancement (LGE) and myocardial wall thickness in a swine model of healed left ventricular infarction.

Methods:
Six swine with healed myocardial infarction underwent cardiovascular magnetic resonance imaging and electroanatomic mapping. Two healthy controls (one treated with amiodarone and one unmedicated) underwent electroanatomic mapping with identical protocols to establish the baseline CV. CV was estimated using a triangulation technique. LGE+ regions were defined as signal intensity >2 SD than the mean of remote regions, wall thinning+ as those with wall thickness <2 SD than the mean of remote regions. LGE heterogeneity was defined as SD of LGE in the local neighborhood of 5 mm and wall thickness gradient as SD within 5 mm. Cardiovascular magnetic resonance and electroanatomic mapping data were registered, and hierarchical modeling was performed to estimate the mean difference of CV (LGE+/−, wall thinning+/−), or the change of the mean of CV per unit change (LGE heterogeneity, wall thickness gradient).

Results:

Significantly slower CV was observed in LGE+ (0.33±0.25 versus 0.54±0.36 m/s;
P
<0.001) and wall thinning+ regions (0.38±0.28 versus 0.55±0.37 m/s;
P
<0.001). Areas with greater LGE heterogeneity (
P
<0.001) and wall thickness gradient (
P
<0.001) exhibited slower CV.

Conclusions:
Slower CV is observed in the presence of LGE, myocardial wall thinning, high LGE heterogeneity, and a high wall thickness gradient. Cardiovascular magnetic resonance may offer a valuable imaging surrogate for estimating CV, which may support noninvasive identification of the arrhythmogenic substrate.
Potential Vorticity Diagnostics to Quantify Effects of Latent Heating in Extratropical Cyclones. Part II: Application to Idealized Climate Change Simulations
Authors: Büeler Dominik , Pfahl Stephan 
Published: April 2019

Abstract
It is still debated how enhanced cloud-condensational latent heating (LH) in a warmer and moister climate may affect the dynamics of extratropical cyclones. In this study, a diagnostic method that explicitly quantifies the contribution of LH to the lower-tropospheric cyclonic potential vorticity (PV) anomaly is used to investigate the effects of stronger LH on the dynamics, intensity, and impacts of cyclones in two conceptually different sets of idealized climate change simulations. A first set of regional surrogate climate change simulations of individual moderate to intense Northern Hemisphere cyclones in a spatially homogeneously 4-K-warmer climate reveals that enhanced LH can largely but not exclusively explain the substantially varying increase in intensity and impacts of most of these cyclones. A second set of idealized aquaplanet GCM simulations demonstrates that the role of enhanced LH becomes multifaceted for large ensembles of cyclones if climate warming is additionally accompanied by changes in the horizontal and vertical temperature structure: cyclone intensity increases with warming due to the continuous increase in LH, reaches a maximum in climates warmer than present day, and decreases beyond a certain warming once the increase of LH is overcompensated by the counteracting reduction in mean available potential energy. Because of their substantially stronger increase in LH, the most intense cyclones reach their maximum intensity in warmer climates than moderately intense cyclones with weaker LH. This suggests that future projections of the extreme tail of the storm tracks might be particularly sensitive to a correct representation of LH.
Environmental Conditions Modulating Tropical Cyclone Formation over the Bay of Bengal during the Pre-Monsoon Transition Period
Authors: Li Zhi , Yu Weidong , Li Kuiping , Wang Huiwu , Liu Yanliang 
Published: April 2019

AbstractGlobally, the highest formation rate of super tropical cyclones (TCs) occurs over the Bay of Bengal (BoB) during the premonsoon transition period (PMT), but TC genesis has a low frequency here. TCs have occurred over the BoB in only 20 of the past 36 years of PMTs (1981–2016). This study investigates which environmental conditions modulate TC formation during the PMT over the BoB by conducting a quantitative analysis based on the genesis potential parameter, vorticity tendency equation, and specific humidity budget equation. The results show that there is a cyclonic anomaly in the TC genesis group compared to the non-TC genesis group, which is mainly due to the divergence term. A significant difference in vorticity contributes to TC formation over the BoB during the PMT. Furthermore, anomalous cyclonic flow enhances ascending motion, transporting moisture to the midlevel atmosphere. A change in specific humidity (SH) causes an increase in relative humidity, which contributes positively to TC formation. The vertical wind shear also makes a small positive contribution. In contrast to the previous three terms, the contribution from the instability term associated with 500- and 850-hPa air temperatures is negative and almost negligible. In addition, the synoptic-scale disturbance energy is more powerful in the TC genesis group than in the non-TC genesis group, which is favorable for TC breeding. Together, these conditions determine whether TCs are generated over the BoB during the PMT.
Interdecadal Variation of Precipitation over the Hengduan Mountains during Rainy Seasons
Authors: Dong Danhong , Tao Weichen , Lau William K. M. , Li Zhanqing , Huang Gang , Wang Pengfei 
Published: April 2019

AbstractThe present study investigates the interdecadal variation of precipitation over the Hengduan Mountains (HM) during rainy seasons from various reanalysis and observational datasets. Based on a moving t test and Lepage test, an obvious rainfall decrease is identified around 2004/05. The spatial distribution of the rainfall changes exhibits large and significant precipitation deficits over the southern HM, with notable anomalous lower-level easterly divergent winds along the southern foothills of the Himalayas (SFH). The anomalous easterlies are located at the northern edge of two cyclones, with two centers of positive rainfall anomalies over the west coast of India (WCI) and the Bay of Bengal (BOB). Observational evidence and numerical experiments demonstrate that the decadal changes of SST over the WP and WIO suppress rainfall over the eastern Indian Ocean (EIO) through large-scale circulation adjustment. The EIO dry anomalies trigger the cross-equatorial anticyclonic wind anomalies as a Rossby wave response, and further cause anomalous meridional circulation and moisture transport over the WCI and BOB, favoring the rainfall increase there. The anomalous easterlies at the northern edge of two cyclones induced by the wet anomalies–related heating cause the divergence anomalies along the SFH, resulting in the reduction of precipitation in the HM. In turn, the two anomalous cyclones and dry anomalies have positive feedback on the wet and easterly wind anomalies, respectively, emphasizing the importance of the circulation–heating interaction.
Local and Downstream Relationships between Labrador Sea Water Volume and North Atlantic Meridional Overturning Circulation Variability
Authors: Li Feili , Lozier M. Susan , Danabasoglu Gokhan , Holliday Naomi P. , Kwon Young-Oh , Romanou Anastasia , Yeager Steve G. , Zhang Rong 
Published: April 2019

Abstract
While it has generally been understood that the production of Labrador Sea Water (LSW) impacts the Atlantic meridional overturning circulation (MOC), this relationship has not been explored extensively or validated against observations. To explore this relationship, a suite of global ocean–sea ice models forced by the same interannually varying atmospheric dataset, varying in resolution from non-eddy-permitting to eddy-permitting (1°–1/4°), is analyzed to investigate the local and downstream relationships between LSW formation and the MOC on interannual to decadal time scales. While all models display a strong relationship between changes in the LSW volume and the MOC in the Labrador Sea, this relationship degrades considerably downstream of the Labrador Sea. In particular, there is no consistent pattern among the models in the North Atlantic subtropical basin over interannual to decadal time scales. Furthermore, the strong response of the MOC in the Labrador Sea to LSW volume changes in that basin may be biased by the overproduction of LSW in many models compared to observations. This analysis shows that changes in LSW volume in the Labrador Sea cannot be clearly and consistently linked to a coherent MOC response across latitudes over interannual to decadal time scales in ocean hindcast simulations of the last half century. Similarly, no coherent relationships are identified between the MOC and the Labrador Sea mixed layer depth or the density of newly formed LSW across latitudes or across models over interannual to decadal time scales.
Pacific Abyssal Transport and Mixing: Through the Samoan Passage versus around the Manihiki Plateau
Authors: Pratt Larry J. , Voet Gunnar , Pacini Astrid , Tan Shuwen , Alford Matthew H. , Carter Glenn S. , Girton James B. , Menemenlis Dimitris 
Published: April 2019

AbstractThe main source feeding the abyssal circulation of the North Pacific is the deep, northward flow of 5–6 Sverdrups (Sv; 1 Sv ≡ 106 m3 s−1) through the Samoan Passage. A recent field campaign has shown that this flow is hydraulically controlled and that it experiences hydraulic jumps accompanied by strong mixing and dissipation concentrated near several deep sills. By our estimates, the diapycnal density flux associated with this mixing is considerably larger than the diapycnal flux across a typical isopycnal surface extending over the abyssal North Pacific. According to historical hydrographic observations, a second source of abyssal water for the North Pacific is 2.3–2.8 Sv of the dense flow that is diverted around the Manihiki Plateau to the east, bypassing the Samoan Passage. This bypass flow is not confined to a channel and is therefore less likely to experience the strong mixing that is associated with hydraulic transitions. The partitioning of flux between the two branches of the deep flow could therefore be relevant to the distribution of Pacific abyssal mixing. To gain insight into the factors that control the partitioning between these two branches, we develop an abyssal and equator-proximal extension of the “island rule.” Novel features include provisions for the presence of hydraulic jumps as well as identification of an appropriate integration circuit for an abyssal layer to the east of the island. Evaluation of the corresponding circulation integral leads to a prediction of 0.4–2.4 Sv of bypass flow. The circulation integral clearly identifies dissipation and frictional drag effects within the Samoan Passage as crucial elements in partitioning the flow.