Search PubMed⌕ Search

Biomedical subjects

P Walters

Publications and source records attributed to P Walters.

15 recordsLinked to original sources
PubMed2006

System size and centrality dependence of charged hadron transverse momentum spectra in Au + Au and Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV.

We present transverse momentum distributions of charged hadrons produced in Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. The spectra are measured for transverse momenta of 0.25 < pT < 5.0 GeV/c at square root of SNN = 62.4 GeV and 0.25 < pT < 7.0 GeV/c at square root of SNN = 200 GeV, in a pseudorapidity range of 0.2 < eta < 1.4. The nuclear modification factor R(AA) is calculated relative to p + p data at both collision energies as a function of collision centrality. At a given collision energy and fractional cross section, R(AA) is observed to be systematically larger in Cu + Cu collisions compared to Au + Au. However, for the same number of participating nucleons, R(AA) is essentially the same in both systems over the measured range of pT, in spite of the significantly different geometries of the Cu + Cu and Au + Au systems.

Journal Article↗
PubMed2006

Digestive proteinases of the larger black flour beetle, Cynaeus angustus (Coleoptera: Tenebrionidae).

Digestion in the larger black flour beetle, Cynaeus angustus (LeConte), was studied to identify new control methods for this pest of stored grains and grain products. The physiological pH of the larval gut, as measured with extracts in water, was approximately 6.1, and the pH for optimal hydrolysis of casein by gut extracts was 6.2 when buffers were reducing. However, under non-reducing conditions, hydrolysis of casein and synthetic serine proteinase substrates was optimal in alkaline buffer. Three major proteinase activities were observed in zymograms using casein or gelatin. Caseinolytic activity of C. angustus gut extracts was inhibited by inhibitors that target aspartic and serine proteinase classes, with minor inhibition by a cysteine proteinase inhibitor. In particular, soybean trypsin and trypsin/chymotrypsin inhibitors were most effective in reducing the in vitro caseinolytic activity of gut extracts. Based on these data, further studies are suggested on the effects of dietary soybean inhibitors of serine proteinases, singly and in combination with aspartic and cysteine proteinase inhibitors, on C. angustus larvae. Results from these studies can be used to develop new control strategies to prevent damage to grains and stored products by C. angustus and similar coleopteran pests.

Animals↗
PubMed2001

Behavioral and histological outcomes following graded spinal cord contusion injury in the C57Bl/6 mouse.

A computer-controlled electromagnetic spinal cord injury device (ESCID) has been adapted to develop a mouse model of spinal cord contusion injury. In the present study, we have extended this model in C57Bl/6 mice with behavioral and histopathological outcome assessment. Three groups of mice received a laminectomy at the T(9) vertebral level followed by a contusion injury from a predetermined starting load of 1500 dynes. Contusion was produced by rapid displacement of the spinal cord to a peak distance of 0.3, 0.5, or 0.8 mm, with the entire injury and retraction procedure completed over a 23-ms epoch. Control groups received laminectomy alone or complete transection. Functional recovery was examined for 9 weeks after injury using the BBB locomotor rating scale, grid walking, and footprint analysis. Distinct patterns of locomotor recovery were evident across the five groups. Measurements of spared white matter at the epicenter, lesion length, and cross-sectional area of fibronectin-immunopositive scar tissue were also significantly different between injury groups. The severity of injury corresponded with the biomechanical measures recorded at the time of impact as well as with behavioral and histological parameters. The results demonstrate that graded contusion injuries can be produced reliably in mice using the ESCID. The data provide a thorough and quantitative analysis of the effects of contusion injury on long-term behavioral and histological outcome measures in this strain and species.

Animals↗
PubMed1998

Autologous skin banking.

Small amounts of excess autograft are commonly harvested during burn procedures, and typically these are discarded. However, the resources of a local skin bank may be used to preserve this tissue for a later autologous use. This has been a routine practice in our institution and we feel that it has impacted favorably on patient care. In this paper we report 42 consecutive applications of autologous frozen skin and illustrate the technique with a case report.

Adolescent↗
PubMed1997

Do you know what a dietetic technician can do? A focus on clinical technicians and their expanded roles and responsibilities.

Dietetic technicians, registered, play a key role in providing quality, cost-effective client care and foodservice management and are guided by the mission statement of the American Dietetic Association to promote optimal nutrition, health, and well-being. Many organizations use dietetic technicians to complete the screening and/or basic level assessments. The dietetic technician also can assist with patient monitoring and complete such tasks as calculating and documenting calorie counts, providing basic diet instruction, monitoring diet consumption and compliance, and determining tolerance of nutritional supplements. Since the last role delineation study was conducted, dietetic technicians have expanded into many different work settings, and practice roles have changed accordingly.

Allied Health Personnel↗
PubMed1997

Validation of the MCMI-III PTSD scale among combat veterans.

The new MCMI-III Posttraumatic Stress Disorder (PTSD) scale was validated on 104 combat veterans who were divided into two groups, PTSD Treatment Group and Non-PTSD Treatment Group. PTSD status was carefully determined by clinical interview and therapists' reports. The Combat Exposure Scale, the Mississippi Scale for Combat-related PTSD, and the Impact of Events Scale were also given. Analysis showed that the MCMI-III PTSD scale had a low internal consistency, but that it significantly differentiated the two groups and significantly correlated to those on other PTSD self-report scales. This scale appeared to be influenced by an acquiescent response style. Further validation studies are needed.

Adult↗
PubMed1996

A comparison of aural and rectal temperature measurements in children with moderate and severe injuries.

OBJECTIVE: The purpose of this study was to compare initial rectal and aural (i.e., ear-based) temperature measurements in children with moderate and severe injuries during their trauma care in the emergency department. DESIGN: A cross-sectional, prospective design was used to compare aural temperature and rectal temperatures in injured children. SAMPLE/SETTING: A convenience sample of 40 children who met the study inclusion criteria were enrolled at the level I pediatric regional resource trauma center in western Pennsylvania. METHODS: Aural temperature was measured by infrared technology (IVAC Corporation, San Diego, Calif.), and rectal temperatures were measured with a thermistor (IVAC Corporation). RESULTS: The subjects (N = 40) ranged in age from 1 to 14 years (mean 6.9 years; SD = 4.4 years). The mean difference between rectal and aural temperature measurements (mean = -0.3 degree C; SD = 0.76 degree C) was statistically significant when compared with a paired t test (p < 0.05). The Pearson product-moment correlation coefficient between aural and rectal temperature measurements was moderate to high (r = 0.85). CONCLUSION: The moderate to high correlation between the two methods shows promise for use of aural infrared temperature measurements as a screening measure for children with moderate and severe injuries.

Adolescent↗
PubMed1987

Effectiveness of a Prudhoe Bay crude oil and its aliphatic, aromatic and heterocyclic fractions in inducing mortality and aryl hydrocarbon hydroxylase in chick embryo in ovo.

Prudhoe Bay crude oil (PBCO) and its aliphatic, aromatic and heterocyclic fractions were tested on the developing chick embryo for (i) embryotoxicity (ii) their ability to induce hepatic and renal cytochrome P450 levels as well as hepatic, renal and pulmonary aryl hydrocarbon hydroxylase activities. On the basis of its concentration in PBCO, the aromatic fraction was responsible for most of the embryotoxicity as well as for the enzyme inducing ability. The NOS fraction constituted less than 7% (w/v) of PBCO but, on a weight equivalent basis, was roughly as potent as the aromatic fraction in causing embryotoxicity and in inducing cytochrome P450 levels and aryl hydrocarbon hydroxylase. The aliphatic fraction was found to be essentially inactive. The results are consistent with the concept that elevation of aryl hydrocarbon hydroxylase levels by certain components of PBCO may lead to increased embryotoxicity.

Animals↗
PubMed1981

Oxygen fields in specific spinal loci of the canine spinal cord.

Oxygen tension (PO2) measurements were made in the dog spinal cord with a small recessed-tip oxygen microelectrode. The use of vibration and specific marking techniques has allowed the elimination of tissue compression artifacts and the mapping of regional PO2 in the thoracic spinal cord. A symmetrical distribution of PO2 values can be shown for the lateral white funiculi; the gray matter and dorsal columns have multimodal distributions. Statistical evaluation showed all these areas to have different PO2 profiles; PO2 values (mmHg) were 61.2 +/- 12.4 for the lateral white funiculi, 55.3 +/- 19.0 for the dorsal columns, and 30.0 +/- 13.6 in spinal gray. The relatively normal distribution patterns of these oxygen tensions indicate that traditional statistical methods may be used to compare and evaluate oxygen diffusion fields in the adult spinal cord.

Animals↗
PubMed1976

Thromboxane - synthesizing activity in guinea pig lung microsomes.

The microsomal fraction of guinea pig lung contains the enzymatic activity that converts arachidonic acid to thromboxane B2. The properties of guinea pig lung enzyme are generally similar to the human platelet enzyme, except the lung enzyme is unstable at 37 degrees C. No difference in total enzymatic activity is observed in the normal and sensitized guinea pig lungs.

Animals↗