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1.
Sci Data ; 11(1): 860, 2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39122730

ABSTRACT

We present a one-year-long multi-sensor dataset collected from honey bee colonies (Apis mellifera) with rich phenotypic measurements. Data were collected non-stop from April 2020 to April 2021 from 53 hives located at two apiaries in Québec, Canada. The sensor data included audio features, temperature, and relative humidity. The phenotypic measurements contained beehive population, number of brood cells (eggs, larva and pupa), Varroa destructor infestation levels, defensive and hygienic behaviors, honey yield, and winter mortality. Our study is amongst the first to combine a wide variety of phenotypic trait measurements annotated by apicultural science experts with multi-sensor data, which facilitate a broader scope of analysis. We first summarize the data collection procedure, sensor data pre-processing steps, and data composition. We then provide an overview of the phenotypic data distribution as well as a visualization of the sensor data patterns. Lastly, we showcase several hive monitoring applications based on sensor data analysis and machine learning, such as winter mortality prediction, hive population estimation, and the presence of an active and laying queen.


Subject(s)
Phenotype , Bees , Animals , Varroidae , Honey , Quebec , Machine Learning , Seasons
2.
J Phys Condens Matter ; 34(18)2022 Mar 02.
Article in English | MEDLINE | ID: mdl-35100572

ABSTRACT

Valleytronic as a hot topic in recent years focuses on electrons' valley degree of freedom as a quantum information carrier. Here, by combining two-bandk.pmodel with high-throughput density functional theory (DFT) calculations, the valley states of Janus 2H-VSSe monolayer are studied which have spontaneous polarization. Nonvolatile valley polarization state is mainly arises from intrinsic ferromagnetism contributed by V-3d electronic configuration and not the spontaneous out-of-plane dipole moment of VSSe monolayer. The effective Hamiltonian model and DFT calculations both showed that the valley splitting mainly originates from the smaller spin splitting coming from the spin-orbit coupling effect rather than the spin splitting of magnetic exchange field. By using the effective Dirac Hamiltonian and Kubo formula, we further calculated the longitudinal and transversal conductivities and absorption spectra of VSSe monolayer which exhibits an anomalous valley Hall effect and clear valley-selective circular dichroism. Our calculations indicate that the modification of valley and spin splitting related to Berry curvature by applying an external strain is more noticeable than by the change of the magnetic moment orientation and electric field. We found that carriers accumulation with particular spin and valley label can be manipulated by tuning effective Hamiltonian parameters. The coexistence of robust in-plane magnetic ordering and spontaneous valley polarization of 2H-VSSe monolayer supports the possibility of applications in spintronics, valleytronics and optoelectronics devices.

3.
Acta Chim Slov ; 67(3): 866-875, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33533418

ABSTRACT

Supported molybdic acid on nano-Fe3O4@TiO2 (Fe3O4@TiO2@(CH2)3OMoO3H) has been successfully prepared, char-acterized and applied as a catalyst for the synthesis of sulfonamide containing coumarin moieties. The prepared Fe3O4nanoparticles by coprecipitation of Fe2+ and Fe3+ ions were treated with tetraethyl orthotitanate to obtain Fe3O4@TiO2. By anchoring 3-chloropropyltriethoxysilan on Fe3O4@TiO2 followed by reacting with molybdic acid, the desired catalyst was produced. The synthesized catalyst was characterized using XRD, SEM, EDS, FT-IR and VSM analysis. Fe3O4@TiO2@(CH2)3OMoO3H was used as a catalyst for the synthesis of sulfonamide containing coumarin moieties via a three-com-ponent reaction of aryl aldehydes, para-toluenesulfonamide and 4-hydroxycoumarin or 5,7-dihydroxy-4-methylcou-marin. The catalyst recovery test showed the catalyst is highly reusable without losing its activity.


Subject(s)
Coumarins/chemical synthesis , Magnetite Nanoparticles/chemistry , Sulfonamides/chemical synthesis , Catalysis , Magnetic Phenomena , Molybdenum/chemistry , Titanium/chemistry
4.
Indian J Dermatol ; 60(2): 206-8, 2015.
Article in English | MEDLINE | ID: mdl-25814721
5.
Res Cardiovasc Med ; 3(1): e13986, 2014 Feb.
Article in English | MEDLINE | ID: mdl-25478529

ABSTRACT

BACKGROUND: The current trend of heart transplantation in recent years has taken a quantum leap forward. We decided to look back at our experience in this center. OBJECTIVES: Here, we focus on the diagnostic pitfalls and challenges in these biopsies. PATIENTS AND METHODS: Forty two patients based on the standard protocol of heart transplantation group, yielded 63 biopsy samples over a period of 33 months (April 2010 - December 2012). The mean age was 30.4 years (ranging from 16 to 58 years) with 51 males (81%) and 12 females (19%). All the patients were examined periodically and biopsy samples were taken from the right ventricular wall. RESULTS: Rarely fewer than three pieces of myocardial samples were procured. Scar, adipose tissues and blood clots may be seen instead. Quilty effect (nodular endocardial lesions composed of inflammatory cell infiltrates) was seen in 8 cases (12.7%). Other findings not directly related to rejection including early ischemic injury, Quilty effect and post-transplant lymphoproliferative disorders (PTLD) were not encountered. CONCLUSIONS: Specimen inadequacy was not a major problem in our center. It poses a great limitation, because suboptimal specimens sometimes mislead the pathologist. Other findings especially Quilty effect were within the range defined for this finding.

6.
Indian J Surg ; 75(Suppl 1): 316-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-24426603

ABSTRACT

In this report, a case of blue toe syndrome related to persistent sciatic artery pseudoaneurysm in a 63-year-old woman, which was diagnosed by selective angiography, is presented. The pseudoaneurysm was successfully treated with coil embolization with good clinical results. A persistent sciatic artery is a rare embryological anomaly that occurs when the sciatic artery fails to regress during fetal development. Therefore, thromboembolisms from persistent sciatic artery aneurysm are rare.

7.
J Am Acad Dermatol ; 65(6): 1180-5, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21550690

ABSTRACT

BACKGROUND: Although several studies have documented an undersupply of dermatologic services in the United States, little is known about the dermatopathology workforce. OBJECTIVE: Objectives included the following: (1) describe the dermatopathology workforce in the United States; (2) identify characteristics associated with academic dermatopathologists; and (3) explore issues surrounding dermatopathology training. METHODS: We conducted a cross-sectional survey of all Fellows of the American Society of Dermatopathology (ASDP) practicing in the United States and its territories. RESULTS: Of 913 ASDP Fellows, 437 (48%) returned a completed questionnaire. Most were male (72%), Caucasian (85%), and had graduated from US/Canadian medical schools (88%). Approximately half (49%) had completed a dermatology residency and a quarter (24%) were in academia. As compared with those in private practice, academic dermatopathologists were more likely to be female (P = .0028), have a medical degree only (P = .0197), and earn $300,000 or less annually (P < .0001). No associations were identified for practice type with either location of medical school (United States/Canada vs other) or year of fellowship graduation (≤1996 vs ≥1997). Although most respondents were satisfied overall with their training, the most common areas identified as inadequate included: coding/billing (47%), biostatistics (38%), pediatric clinical dermatology (27%), and electron microscopy (27%). LIMITATIONS: Moderate response rate and potential recall bias are limitations. CONCLUSIONS: This study of the US dermatopathology workforce provides benchmarks for future studies and strategies for workforce planning.


Subject(s)
Dermatology , Pathology , Adult , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , United States , Workforce
8.
Biochem J ; 378(Pt 2): 569-77, 2004 Mar 01.
Article in English | MEDLINE | ID: mdl-14616089

ABSTRACT

Anthrax lethal toxin is the major cause of death in systemic anthrax. Lethal toxin consists of two proteins: protective antigen and LF (lethal factor). Protective antigen binds to a cell-surface receptor and transports LF into the cytosol. LF is a metalloprotease that targets MKKs [MAPK (mitogen-activated protein kinase) kinases]/MEKs [MAPK/ERK (extracellular-signal-regulated kinase) kinases], cleaving them to remove a small N-terminal stretch but leaving the bulk of the protein, including the protein kinase domain, intact. LF-mediated cleavage of MEK1 and MKK6 has been shown to inhibit signalling through their cognate MAPK pathways. However, the precise mechanism by which this proteolytic cleavage inhibits signal transmission has been unclear. Here we show that the C-terminal LF-cleavage products of MEK1, MEK2, MKK3, MKK4, MKK6 and MKK7 are impaired in their ability to bind to their MAPK substrates, suggesting a common mechanism for the LF-induced inhibition of signalling.


Subject(s)
Antigens, Bacterial , Bacterial Toxins/metabolism , MAP Kinase Kinase 4 , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Amino Acid Sequence , Animals , Bacterial Toxins/pharmacology , Binding Sites , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Humans , JNK Mitogen-Activated Protein Kinases , MAP Kinase Kinase 1 , MAP Kinase Kinase 2 , MAP Kinase Kinase 3 , MAP Kinase Kinase 6 , MAP Kinase Kinase 7 , MAP Kinase Signaling System/drug effects , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinase Kinases/chemistry , Molecular Sequence Data , Protein-Tyrosine Kinases/metabolism , Rats , Sequence Alignment , p38 Mitogen-Activated Protein Kinases
9.
J Biol Chem ; 278(35): 32662-72, 2003 Aug 29.
Article in English | MEDLINE | ID: mdl-12788955

ABSTRACT

Specific docking interactions between MAPKs and their activating MAPK kinases (MKKs or MEKs) are crucial for efficient and accurate signal transmission. Here, we report the identification of a MAPK-docking site, or "D-site," in the N terminus of human MKK4/JNKK1. This docking site conforms to the consensus sequence for known D-sites in other MKKs and contains the first of the two cleavage sites for anthrax lethal factor protease that have been found in the N terminus of MKK4. This docking site was both necessary and sufficient for the high affinity binding of the MAPKs JNK1, JNK2, JNK3, p38 alpha, and p38 beta to MKK4. Mutations that altered conserved residues in this docking site reduced JNK/p38 binding. In addition, a peptide version of this docking site, as well as a peptide version of the JNK-binding site of the JIP-1 scaffold protein, inhibited both MKK4/JNK binding and MKK4-mediated phosphorylation of JNK1. These same peptides also inhibited JNK2-mediated phosphorylation of c-Jun and ATF2, suggesting that transcription factors, MKK4, and the JIP scaffold compete for docking to JNK. Finally, the selectivity of the MKK4, MEK1, and MEK2 D-sites for JNK versus ERK was quantified. The MEK1 and MEK2 D-sites displayed a strong selectivity for their cognate MAPK (ERK2) versus a non-cognate MAPK (JNK). In contrast, the MKK4 D-site exhibited only limited selectivity for JNK versus ERK.


Subject(s)
MAP Kinase Kinase 4 , MAP Kinase Signaling System , Mitogen-Activated Protein Kinase Kinases/chemistry , Amino Acid Motifs , Amino Acid Sequence , Binding Sites , Codon , Conserved Sequence , DNA Primers/pharmacology , Dose-Response Relationship, Drug , Glutathione Transferase/metabolism , Humans , Kinetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 10 , Mitogen-Activated Protein Kinase 11 , Mitogen-Activated Protein Kinase 8 , Mitogen-Activated Protein Kinase 9 , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Molecular Sequence Data , Peptides/chemistry , Phosphorylation , Plasmids/metabolism , Protein Binding , Protein Biosynthesis , Protein Structure, Tertiary , Protein-Tyrosine Kinases/metabolism , Recombinant Fusion Proteins/metabolism , Transcription, Genetic , p38 Mitogen-Activated Protein Kinases
10.
Biochem J ; 370(Pt 3): 1077-85, 2003 Mar 15.
Article in English | MEDLINE | ID: mdl-12529172

ABSTRACT

Mitogen-activated protein kinase (MAPK) cascades control gene expression patterns in response to extracellular stimuli. MAPK/ERK (extracellular-signal-regulated kinase) kinases (MEKs) activate MAPKs by phosphorylating them; activated MAPKs, in turn, phosphorylate target transcription factors, and are deactivated by phosphatases. One mechanism for maintaining signal specificity and efficiency is the interaction of MAPKs with their substrates and regulators through high-affinity docking sites. In the present study, we show that peptides corresponding to the MAPK-docking sites of MEK1, MEK2, Ste7, Elk-1 and MAPK phosphatase (MKP)-2 potently inhibit MEK2 phosphorylation of ERK2, ERK2 phosphorylation of Elk-1, and MKP-1 dephosphorylation of ERK2. Each peptide inhibited multiple reactions; for example, the MEK2 peptide inhibited not only MEK2, but also ERK2 and MKP-1. In addition, these docking-site peptides inhibited MEK2-ERK2 binding. The MAPK-docking site of MEK1 also potently stimulated ERK2-mediated phosphorylation of a target site on the same peptide. Control peptides with mutations of conserved basic and hydrophobic residues of the MAPK-docking site consensus lacked biological activity. We conclude that MEKs, MKPs and the Elk-1 transcription factor compete for binding to the same region of ERK2 via protein-protein interactions that are crucial for kinase/phosphatase activity.


Subject(s)
MAP Kinase Signaling System/physiology , Mitogen-Activated Protein Kinases/metabolism , Protein Tyrosine Phosphatases/metabolism , Transcription Factors/metabolism , Amino Acid Sequence , Binding Sites , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Dual Specificity Phosphatase 1 , MAP Kinase Kinase 1 , MAP Kinase Kinase 2 , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase Kinases/genetics , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/genetics , Molecular Sequence Data , Peptides/genetics , Peptides/metabolism , Phosphorylation , Protein Binding , Protein Kinases/genetics , Protein Kinases/metabolism , Protein Phosphatase 1 , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Protein Tyrosine Phosphatases/genetics , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Sequence Alignment , Transcription Factors/genetics
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