The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study.
Hand Strength ; Hand* ; Vibration*

Objective : To explore differential expression of insulin like growth factor 1( IGF1) in oral squamous cell carcinoma (OSCC) tissues and cells , and to analyze its clinical significance of IGF1 . Methods : The protein expression of IGF1 was detected in 115 OSCC tissues (OSCC group) and 74 normal tissues (normal group) using immunohistochemical technique , and the relationship with the clinicopathological factors and prognosis of OSCC was analyzed. The IGF1 protein and mRNA levels in HOK and OSCC cell lines ( CAL⁃27 , TCA⁃8113 , SCC⁃15 and SCC⁃25) were detected by Western blot and qRT⁃PCR. Results : The high expression rate of IGF1 in OSCC group was 72. 17% , which was significantly higher than that in normal group (2. 70% ) ( P < 0. 001) . The proportion under ROC curve (AUC) of OSCC diagnosed by IGF1 was 0. 81 , the sensitivity was 0. 73 , and the specificity was 0. 82. The expression of IGF1 was related to the degree of differentiation , T stage and depth of invasion (P = 0. 03 , P = 0. 02 , P = 0. 02) , but not to gender, age , N stage , TNM stage , smoking , alcohol consumption , or HPV infection (P > 0. 05) . Kaplan⁃Meier and COX regression analysis showed that the high expression of IGF1 , the degree of differentiation , the T stage and the depth of infiltration were the related factors affecting the prognosis of patients (P < 0. 01 , P = 0. 04 , P = 0. 03 , P = 0. 04) . COX multivariate indicated that high expression of IGF1 was an independent factor affecting the prognosis of patients ( P = 0. 01) . Western blot and qRT⁃PCR results indicated that the expression of IGF1 in OSCC cell lines was higher than that in HOK (P < 0. 05) . Conclusion IGF1 can be a potential diagnostic and poor prognostic marker in oral squamous cell carcinoma.

Objective: To explore the current status of village doctors′ vulnerability in Shandong province in the context of ongoing healthcare reform. Methods: A cross-section study was conducted from October 2015 to November 2015 based on a self-designed questionnaire for village doctors. The questionnaire included 6 parts: fundamental state, disturbance from surroundings, disturbance from job, emotional support, instrumental support and self-ability of village doctors. Mean and standard deviation were adopted to describe the level of disturbance and support. Quadrant analysis was adopted to analyze village doctors′ vulnerability. The set pair analysis was adopted to calculate the vulnerability index and sample cluster analysis was adopted to classify village doctors based on the vulnerability index. Results: The total disturbance score was 3.39±0.46, and contribution from professional risk was the biggest(19.95%). The self-ability score was 3.33±0.40, and contribution from financial support was the smallest(4.09%). According to the set pair analysis, village doctors′ vulnerability total score was 0.49±0.06, ranging in a medium category. According to the sample cluster analysis, 27.2%(277/1 018)of the village doctors stayed at the upper category, as 30.3%(309/1 018) was defined as a medium category. According to the quadrant analysis, 35.5%(361/1 018)of the village doctors were found as in crisis vulnerability. Conclusions In general, village doctors′ vulnerability stays in the medium category. They have to fight against high disturbance from surroundings, with more emotional support and less financial support expected.