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1.
Environ Monit Assess ; 193(5): 307, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33909163

ABSTRACT

Metal and metalloid contamination in drinking water sources is a global concern, particularly in developing countries. This study used hollow membrane water filters and metal-capturing polyurethane foams to sample 71 drinking water sources in 22 different countries. Field sampling was performed with sampling kits prepared in the lab at Hope College in Holland, MI, USA. Filters and foams were sent back to the lab after sampling, and subsequent analysis of flushates and rinsates allowed the estimation of suspended solids and metal and other analayte concentrations in source waters. Estimated particulate concentrations were 0-92 mg/L, and consisted of quartz, feldspar, and clay, with some samples containing metal oxides or sulfide phases. As and Cu were the only analytes which occurred above the World Health Organization (WHO) guidelines of 10 µg/L and 2000 µg/L, respectively, with As exceeding the guideline in 45% of the sources and Cu in 3%. Except for one value of ~ 285 µg/L, As concentrations were 45-200 µg/L (river), 65-179 µg/L (well), and 112-178 µg/L (tap). Other metals (Ce, Fe, Mg, Mn, Zn) with no WHO guideline were also detected, with Mn the most common. This study demonstrated that filters and foams can be used for reconnaissance characterization of untreated drinking water. However, estimated metal and other analyte concentrations could only be reported as minimum values due to potential incomplete retrieval of foam-bound analytes. A qualitative reporting methodology was used to report analytes as "present" if the concentration was below the WHO guideline, and "present-recommend retesting" if the concentration was quantifiable and above the WHO guideline.


Subject(s)
Drinking Water , Metalloids , Metals, Heavy , Water Pollutants, Chemical , Environmental Monitoring , Humans , Metalloids/analysis , Metals, Heavy/analysis , Netherlands , Water Pollutants, Chemical/analysis
2.
Opt Express ; 26(11): 13850-13864, 2018 May 28.
Article in English | MEDLINE | ID: mdl-29877431

ABSTRACT

We demonstrate a strategy for increasing the operating temperatures of nBn midwave infrared (MWIR) focal plane arrays, based on the use of two-dimensional plasmonic gratings to enhance the quantum efficiency (QE) of structures with very thin absorbers. Reducing the absorber volume correspondingly reduces the dark current in a diffusion-limited photodiode, while light trapping mediated by the plasmonic grating increases the net absorbance to maintain high QE. The plasmonically enhanced nBn MWIR sensors with absorber thicknesses of only 0.5 µm exhibit peak internal QEs as high as 57%, which enables a 5-fold reduction in dark current. Numerical simulations indicate the potential for further improvement.

3.
Gene Ther ; 22(3): 247-56, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25503693

ABSTRACT

In an effort to develop a new therapy for prostate cancer (PCa) bone metastases, we have created Ad.dcn, a recombinant oncolytic adenovirus carrying the human decorin gene. Infection of PC-3 and DU-145, the human prostate tumor cells, with Ad.dcn or a non-replicating adenovirus Ad(E1-).dcn resulted in decorin expression; Ad.dcn produced high viral titers and cytotoxicity in human prostate tumor cells. Adenoviral-mediated decorin expression inhibited Met, the Wnt/ß-catenin signaling axis, vascular endothelial growth factor A, reduced mitochondrial DNA levels and inhibited tumor cell migration. To examine the antitumor response of Ad.dcn, PC-3-luc cells were inoculated in the left heart ventricle to establish bone metastases in nude mice. Ad.dcn, in conjunction with control replicating and non-replicating vectors were injected via tail vein. The real-time monitoring of mice, once a week, by bioluminescence imaging and X-ray radiography showed that Ad.dcn produced significant inhibition of skeletal metastases. Analyses of the mice at the terminal time point indicated a significant reduction in the tumor burden, osteoclast number, serum tartrate-resistant acid phosphatase 5b levels, osteocalcin levels, hypercalcemia, inhibition of cancer cachexia and an increase in the animal survival. Based on these studies, we believe that Ad.dcn can be developed as a potential new therapy for PCa bone metastasis.


Subject(s)
Bone Neoplasms/secondary , Bone Neoplasms/therapy , Decorin/metabolism , Oncolytic Virotherapy , Oncolytic Viruses/metabolism , Prostatic Neoplasms/therapy , Animals , Cell Line, Tumor , Cell Movement/drug effects , Decorin/genetics , Decorin/pharmacology , Disease Models, Animal , Gene Transfer Techniques , Humans , Male , Mice, Nude , Oncolytic Viruses/genetics
4.
Int J Comput Biol Drug Des ; 6(3): 255-62, 2013.
Article in English | MEDLINE | ID: mdl-23900440

ABSTRACT

Traditional two-dimensional (2D) X-ray mammography is the most commonly used method for breast cancer diagnosis. Recently, a three-dimensional (3D) Digital Breast Tomosynthesis (DBT) system has been invented, which is likely to challenge the current mammography technology. The DBT system provides stunning 3D information, giving physicians increased detail of anatomical information, while reducing the chance of false negative screening. In this research, two reconstruction algorithms, Back Projection (BP) and Shift-And-Add (SAA), were used to investigate and compare View Angle (VA) and the number of projection images (N) with parallel imaging configurations. In addition, in order to better determine which method displayed better-quality imaging, Modulation Transfer Function (MTF) analyses were conducted with both algorithms, ultimately producing results which improve upon better breast cancer detection. Research studies find evidence that early detection of the disease is the best way to conquer breast cancer, and earlier detection results in the increase of life span for the affected person.


Subject(s)
Breast Neoplasms/diagnostic imaging , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Mammography/methods , Tomography, X-Ray/methods , Female , Humans
5.
Int J Comput Biol Drug Des ; 3(4): 287-96, 2010.
Article in English | MEDLINE | ID: mdl-21297228

ABSTRACT

Digital tomosynthesis is a novel technology that has been developed for various clinical applications. Parallel imaging configuration is utilised in a few tomosynthesis imaging areas such as digital chest tomosynthesis. Recently, parallel imaging configuration for breast tomosynthesis began to appear too. In this paper, we present the investigation on computational analysis of impulse response characterisation as the start point of our important research efforts to optimise the parallel imaging configurations. Results suggest that impulse response computational analysis is an effective method to compare and optimise imaging configurations.


Subject(s)
Computational Biology/methods , Image Processing, Computer-Assisted/methods , Mammography/methods , Algorithms , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Computer Simulation , Female , Humans
6.
Acad Med ; 75(12): 1215, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11112725

ABSTRACT

Medical students' Balanced Emotional Empathy Scale scores were compared by year, sex, and expressed specialty choice. Scores were lower for students choosing non-core specialties, and for M4 men students compared with M3 men students.


Subject(s)
Empathy , Students, Medical/psychology , Analysis of Variance , Female , Humans , Male , Psychological Tests/statistics & numerical data , Sex Distribution , Students, Medical/statistics & numerical data
7.
J Adolesc Health ; 16(1): 50-2, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7742338

ABSTRACT

PURPOSE: Left-handedness has been suggested as a risk factor for unintentional trauma. The objective of this study was to determine if left-handedness was associated with an increased frequency and severity of injury among adolescent school athletes. METHODS: A questionnaire was administered to 634 junior and senior high school athletes during preparticipation examinations. The questionnaire consisted of a four-item handedness determination and history of past injury. RESULTS: Left-handers more frequently reported having seen a physician in the previous year for treatment of an injury than did right-handers. A higher proportion of the left-handers than right-handers reported having been previously hospitalized for injury treatment. A higher proportion of left-handers than right-handers reported having previously had surgery for treatment of an injury. CONCLUSIONS: Left-handedness appears to be a risk factor for injury among adolescent school athletes.


Subject(s)
Adolescent Behavior , Athletic Injuries/epidemiology , Functional Laterality , Adolescent , Athletic Injuries/etiology , Child , Confidence Intervals , Female , Humans , Male , Risk Factors
8.
J Anim Sci ; 66(6): 1371-7, 1988 Jun.
Article in English | MEDLINE | ID: mdl-3397357

ABSTRACT

Mass selection for an index of increased postweaning average daily gain and decreased backfat thickness was practiced for five generations. Litter size and weight for 221 gilt litters, birth weight and nipple number for 2,242 piglets and weaning weight at 42 d of age for 2,111 pigs were recorded. Carcass measurements were taken on 331 pigs. Differences between means of the lines (select control) were regressed on cumulative selection differential of the index. These regression coefficients were negative (P greater than .10) for total number born, number born alive, number weaned per litter, nipple number and carcass backfat thickness. Coefficients were positive (P greater than .10) for individual pig and litter weights at birth and weaning and for the carcass traits of length, longissimus muscle area and percentage of ham and loin. Absolute values of realized genetic correlations of index with traits evaluated were all .35 or less except the correlation with carcass backfat, which was -.84. None of these was significant; therefore, index selection for lean growth should have little effect on litter size and weight but may have a beneficial effect on carcass backfat.


Subject(s)
Body Composition , Body Weight , Selection, Genetic , Swine/growth & development , Adipose Tissue , Animals , Animals, Newborn , Female , Male
9.
J Anim Sci ; 58(3): 541-4, 1984 Mar.
Article in English | MEDLINE | ID: mdl-6715268

ABSTRACT

Littermate gilts were used to study the effects of exercise during the growing-finishing period on performance, age at puberty and conception rate. In trial 1, 12 gilts walked 15 min daily on a treadmill 6 d/wk (Monday through Saturday) until they attained body weights of about 100 kg, while 12 littermate gilts were not forced to exercise. Initial weight and age averaged 24.7 kg and 74 d, respectively. For trial 2, 12 gilts walked 30 min daily 6 d/wk (Monday through Saturday) on a treadmill, while 12 littermate gilts were not exercised. Initial weight and age of these gilts averaged 26.8 kg and 76 d, respectively. The treadmill was operated at 0 slope and at a speed of 2.6 km/h. Within trial, there were no differences (P greater than .05) in weight gain, average daily gain, feed consumed, feed to gain ratio, average backfat depth of loin eye area between gilts exercised and those not exercised. In both trials, there were no differences (P greater than .05) in age at puberty between exercised and nonexercised gilts. In trial 2, 10 gilts were selected in each of the exercised and nonexercised groups and were hand-mated to the same boar on the second estrous cycle. Eight gilts from the exercised group conceived, while nine from the nonexercised group conceived. Four gilts from the nonexercised groups had severe locomotor problems while only one gilt from the exercised groups had difficulty walking.


Subject(s)
Body Weight , Fertility , Physical Exertion , Sexual Maturation , Swine/physiology , Animals , Body Composition , Female
10.
Proc Natl Acad Sci U S A ; 73(11): 4200-4, 1976 Nov.
Article in English | MEDLINE | ID: mdl-825860

ABSTRACT

An oligomeric intermediate in the biosynthetic pathway of peptidoglycan was isolated from B. megaterium. The oligomer has been identified as [disaccharide(pentapeptide)]12 pyrophosphoryl undecaprenol.


Subject(s)
Bacillus megaterium/metabolism , Glycopeptides/metabolism , Lipid Metabolism , Peptidoglycan/biosynthesis , Kinetics , Molecular Weight
11.
Can Fam Physician ; 13(8): 15-41, 1967 Aug.
Article in English | MEDLINE | ID: mdl-20468115
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