Precipitation over the past four centuries in the Dieshan Mountains as inferred from tree rings: An introduction to an HHT-based method

To improve our understanding of the Asian monsoon system, we developed a hydroclimate reconstruction in a marginal monsoon shoulder region for the period prior to the industrial era. Here, we present the first moisture sensitive tree-ring chronology, spanning 501 years for the Dieshan Mountain area, a boundary region of the Asian summer monsoon in the northeastern Tibetan Plateau. This reconstruction was derived from 101 cores of 68 old-growth Chinese pine (Pinus tabulaeformis) trees. We introduce a Hilbert–Huang Transform (HHT) based standardization method to develop the tree-ring chronology, which has the advantages of excluding non-climatic disturbances in individual tree-ring series. Based on the reliable portion of the chronology, we reconstructed the annual (prior July to current June) precipitation history since 1637 for the Dieshan Mountain area and were able to explain 41.3% of the variance. The extremely dry years in this reconstruction were also found in historical documents and are also associated with El Niño episodes. Dry periods were reconstructed for 1718–1725, 1766–1770 and 1920–1933, whereas 1782–1788 and 1979–1985 were wet periods. The spatial signatures of these events were supported by data from other marginal regions of the Asian summer monsoon. Over the past four centuries, out-of-phase relationships between hydroclimate variations in the Dieshan Mountain area and far western Mongolia were observed during the 1718–1725 and 1766–1770 dry periods and the 1979–1985 wet period.

Range of Motion of the Upper Extremity in a Healthy Pediatric Population: Introduction to Normative Data.

Objective In the pediatric population traumatic injuries of the upper extremity are common. After therapy a decision has to be made if the mobility of the joint lies within a normal range. The purpose of this study was to give an introduction to normative data. We investigate if there is a significant difference in the range of motion (ROM) between male and female probands and furthermore, if an effect of the age can be detected. Methods We performed an institutional review board-approved study of healthy girls and boys aged between 2 and 16 years without any medical history of an upper extremity fracture. We investigated the active ROM of the elbow, wrist, metacarpophalangeal, and interphalangeal joints. Furthermore, age, handedness, weight, and height were recorded. A total of 171 adolescents with a mean age of 10.6 years were included and separated into four cohorts by age: 2 to 5, 6 to 10, 11 to 13, and 14 to 16 years. Results We found significant differences between the genders in the age group from 11 to 13 years for the flexion of the elbow, the pronation, the flexion of the interphalangeal joint of the thumb, as well as the flexion of the metacarpophalangeal joints of digitus II to V. Furthermore, a significant difference in the same joints except from the elbow flexion could be demonstrated between the genders. Conclusion Our study contributes normative data for upper extremity ROM in the pediatric population and presents a gender-related difference in certain joints. Clinical Relevance Normative data for the ROM of upper extremity joints in children is helpful for the evaluation of pediatric orthopedic patients and provides the framework for therapeutic resolution. Since a great number of traumatic injuries in children affect the upper extremity, this information may help the physician to estimate the impact of the injury and decide on the therapeutic management.

An Introduction to mountain glaciers as climate indicators with spatial and temporal diversity

This article gives an introduction to the spatial and temporal diversity of mountain glaciers as climate indicators. Alongside some information about the present extent of mountain glaciation and available databases, some specific problems with the interpretation of mountain glacier changes are highlighted.